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Concrete Casting News from the Hill and Griffith Company

Precast Concrete Form Oil Application

Posted by Chuck Lohre on May 18, 2017 2:33:37 PM

 

NPCA Virtual Tour of US Concrete, a state of the art precast manufacturing facility acquired by Oldcastle Precast in August 2012

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Published on Mar 27, 2014

http://www.oldcastleprecast.com
NPCA Virtual Tour of US Concrete, a state of the art precast manufacturing facility acquired by Oldcastle Precast in August 2012

For more information
http://www.oldcastleprecast.com
1-888-965-3227
National Sales & Marketing Office
7921 Southpark Plaza
Littleton, CO 80120
USA


Hill and Griffith 3.5 Gallon Spray Unit

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Benefits and Advantages

  • Components that come in contact with the concrete form oil are non-reactive.
  • Tri-Poxy Coated Steel
  • 4 Gallon capacity; 3.5 gallon usable
  • Funnel top tank for easy fill and closure
  • Poly Shut off with lock on
  • Heavy duty reinforced hose 600 PSI burst
  • 12” pump assembly (pressurizes with fewer strokes)
  • 24” poly curved extension
  • Padded carrying strap
  • All Vitron™ seals and gaskets
  • Lock-On spray control
  • Easy to clean – no internal components
  • Includes 3 spray tips

Hill and Griffith Customer Service

We're known for our hands on approach. Let us visit your plant and recommend concrete release agents, packerhead concrete form releases, concrete form seasoning, potable water concrete form release, non-petroleum concrete form release, biodegradable concrete form release, rust inhibitors and concrete dissolver products that suit your needs.

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 Bulletins and Technical Papers for Concrete Casting Products

Tags: Concrete Casting Products, concrete release agents, concrete casting supplies, Application of Precast Concrete Form Oil, Grifcote, Concrete Terms Glossary

Concrete Terms Glossary

Posted by Chuck Lohre on May 11, 2017 4:19:23 PM

Concrete Terms Glossary.jpgWhat's "Air content " in concrete and what is "Laitance"? A good concrete terms glossary will help and we'd like to share this one from Overland Concrete in Olathe, Kansas. Enjoy!

And BTW "Laitance" is "A thin layer of fine, loosely bonded particles on the surface of fresh concrete, caused by the upward movement of water. Laitance must be removed before application of a decorative coating or topping."

From their site, "At Overland Concrete, we've built a reputation you can count on because of dedication to quality, responsible, customer-oriented work performed with expert craftsmanship through care and consideration to design and detail. Our family owned business, established in 1994, has grown into Kansas City's premier concrete contracting company by maintaining high standards of top quality materials and expertise that provide value for our customers, making us "Johnson County's Most Often Referred Concrete Contractor."

Contact them at 913-393-4200, PO Box 325, Olathe, KS 66051

 

Overland Concrete's Concrete Terms Glossary

A

Abrams' Law -The rule of concrete stating that with given materials, curing, and testing conditions, concrete strength is inversely related to the ratio of water to cement. Low water-to-cement ratios produce higher concrete strengths

Accelerator - Chemical substance added to a concrete mix that reduces the set time by increasing the rate of hydration.

Aggregate - a mixture of sand, rock, crushed stone, expanded materials, or particles, both enhances the structural performance of concrete and improves cement paste's formation and flow. Aggregate usually constitutes about 75% of concrete volume.

Air-entraining - Air-entrained concrete contains minute air bubbles that are distributed uniformly throughout the cement paste. Entrained air can be produced in concrete by use of an air-entraining cement, by introduction of air-entraining admixture, or by a combination of both methods. Air-entraining admixtures are used to stabilize microscopic air bubbles in concrete. Proper air-entrainment, with appropriate volume and spacing factor, will dramatically improve the durability of concrete exposed to moisture during cycles of freezing and thawing. Entrained air also improves concrete's resistance to surface scaling causes by chemicals deicers.

Acid etching - Application of muriatic or phosphoric acid to clean or profile a concrete surface. Used as an alternative to abrasive blasting for surface preparation.

Acid stain - (or chemical stain) A stain containing inorganic salts dissolved in an acidic, water-based solution that reacts chemically with the minerals in hardened concrete to produce permanent, transparent color that will not peel or flake. Gives concrete an attractive variegated or marbleized appearance. Colors tend to be earth tones, such as tans, browns, reddish browns, and greens.

Acrylic Sealer - An acrylic solvent or water-based sealer that forms a protective film on the surface of the concrete that imparts a sheen that highlights the beauty of regular and decorative concrete.

Admixture - An ingredient in concrete other than water, portland cement, and aggregate used to modify the properties of concrete in its freshly mixed, setting, or hardened states. May be added to concrete at the batch plant or on the job site. Prepackaged admixtures are available for convenient job site addition, giving contractors the ability to modify the concrete they receive when necessary, such as extending the amount of time available for decorative stamping. See: http://www.geigerreadymix.com/

Air content - The amount of entrained or entrapped air in concrete, usually expressed as a percentage of total volume.

ASR (Alkali -Silica Reactivity) - Alkali-silica reactivity is the process in which certain minerals (mostly glass type silica) in the presence of moisture are broken down by the highly alkaline environment of concrete producing a gel that expands creating tensile forces in the concrete matrix which cause cracking of the concrete. The cracking then allows more water to infiltrate into the concrete creating more gel, more expansion etc. Ultimately the concrete fails or disintegrates.

Antiquing - A color layering technique for giving decorative concrete surfaces an aged or mottled appearance.

American Concrete Institute (ACI) - An international organization providing education, certification, and information about concrete.

American National Standards Institute (ANSI) - The United States representative in the International Organization for Standardization (ISO).

American Standard of Testing Materials (ASTM) - An organization that serves as a standardized testing center to evaluate the performance of a variety of building materials.

Apron - A slab of concrete, often at an entrance for vehicles, that extends beyond a building's entrance.

B


Bleed water (bleeding) - Water that rises to the surface of freshly placed concrete due to segregation. Bleeding may interfere with finishing operations. If a dry-shake color hardener is being applied to the concrete surface, some bleed water is needed to wet out the hardener sufficiently so it can be floated into the surface.

Blistering - The formation of blisters in toppings or coatings and the loss of adhesion with the underlying substrate. On concrete surfaces, this is often caused by moisture or moisture vapor transmission problems.

Bond - The degree of adhesion or grip of a material (such as coatings, toppings, repair mortars, or sealers) to an existing surface.

Bonding agent - An adhesive agent used to increase the adherence of coatings or toppings to the existing surface. Also used to bond new concrete to old. Also known as a primer.

Bond breaker - A material that prevents adhesion of materials to a concrete substrate.

Broadcast - To hand toss a dry-shake color hardener, decorative aggregate, or other dry material in a uniform layer over fresh concrete, overlays, or coatings to add color or traction. (Also see seeding.)

Broom finish - Surface texture obtained by pushing a broom over freshly placed concrete.

Bull float - A tool comprising a large flat rectangular blade made of wood, resin, aluminum, or magnesium. Used to eliminate high and low spots in freshly placed concrete slabs, embed large aggregate at the surface, bring a layer of paste to the surface needed during final finishing, and float in dry-shake color hardener. Long handles either clip on or screw into the float head so it can be pushed out onto the slab while the user stands at the perimeter.

C

Calcium chloride - An accelerating admixture to reduce the set time of concrete in cooler, damp weather conditions by increasing the rate of hydration. Calcium chloride can cause a mottling or dappling of the surface color and corrode steel reinforcement in a concrete slab.

Cast in place - Concrete placed and finished in its final location.

Cement - Cement is not the same as concrete, but rather one component of concrete. Cement, a combination of finely ground materials, hardens when mixed with water to become the "glue" in concrete.

Cementitious - A material containing portland cement as one of its components or having cement-like properties.

Chairs (supports) - rebar support chairs allow the reinforcement bars to be supported at a sustained level throughout a concrete slab.

Chalking - Loose, powdery substance caused by deterioration of a concrete surface or degradation of a coating or overlay.

Compressive strength - The maximum compressive stress concrete or cementitious overlay materials are capable of sustaining, expressed as pounds per square inch (psi).

Concrete - Concrete is not the same as cement. Concrete is a combination of cement as a binding agent, chemical additives, water and mineral. This combination, when properly mixed and placed, hardens into an excellent building material for a wide variety of uses.

Concrete countertops - A handcrafted alternative to manufactured countertop surfaces. Can be precast in a shop in molds built to the customer's specifications or cast onsite, by setting a mold on top of the base kitchen cabinets and then filling with concrete. The use of stains, pigments, decorative aggregates, and epoxy coatings can give concrete countertops the look, texture, and feel of quarried stone such as marble, granite, and limestone.

Consistency - The ability of fresh concrete to flow. The usual measure of consistency is slump.

Control (or contraction) joint - Sawed or tooled groove in a concrete slab used to regulate the location of cracking.

Construction Joint - are surfaces where two successive placements of concrete meet. They are typically placed at the end of a day's work, but may be required when concrete placement is stopped for longer than the initial setting time of concrete. In slabs they may be designed to permit movement and/or transfer load.

Crack chasing - Routing out cracks in concrete with a saw or angle grinder before filling with a repair material.

Cracks, moving - Cracks in concrete that are still moving, or active. Often they are structural in nature and continue through the entire depth of the concrete.

Cracks, static - Random, non-moving hairline cracks that only affect the concrete surface (also see craze cracks and plastic shrinkage cracks).

Crazing - A series of fine, random cracks caused by shrinkage of the surface mortar.

Crusting - A condition that occurs when the surface of freshly placed concrete dries too quickly, often due to exposure to direct sun, wind, or high temperatures or with stamped concrete.

Cubic Yard - Unit of measure for ready mix concrete. Concrete is ordered, sold, and batched by volume.

Curing - Action taken to maintain favorable moisture and temperature conditions of freshly placed concrete or cementitious materials during a defined period of time following placement. Helps to ensure adequate hydration and proper hardening.

Curing compound - A liquid that, when applied to the surface of newly placed concrete, forms a membrane on the concrete or penetrates the concrete to retard the evaporation of water.

D

Darby - A longer version of a hand float, ranging in length from 2 to 4 feet. Useful for leveling problem areas.

Decorative aggregate - Richly colored natural stones, such as basalts, granite, quartz, or limestone, used to enhance exposed-aggregate concrete or decorative toppings.

Decorative concrete - Concrete that has been enhanced by color, pattern, texture, or a combination of ornamental treatments.

Degreaser - A chemical solution for removing grease, oils, and other contaminants from concrete surfaces.

Delamination - A separation of a coating or topping from a substrate or the layers of a coating from each other due to poor adhesion. Or in the case of a concrete slab, a horizontal splitting or separation of the upper surface.

Densifier - A penetrating liquid chemical hardener applied to concrete to help solidify and densify the surface and provide extra protection from water penetration and staining. Often recommended for polished concrete, because hard concrete produces a better polish.

Dry-shake color hardener - A mixture of coloring pigments, cement, aggregates, and surface conditioning agents. Applied as a dry shake to stamped concrete or stamped overlays to produce a colorful, wear-resistant surface.

Drying shrinkage - A decrease in the volume of concrete as it dries, due to loss of moisture. See also plastic shrinkage cracks

Dyes - Translucent color solutions containing very fine pigments that penetrate into the concrete surface. Will not chemically react with concrete (like acid stains will). Both water-and solvent-based dyes are available, with colors ranging from soft pastels to bolder hue

E

Edger - A tool used on the edges of fresh concrete to provide a clean, finished edge.

Engraving - The use of special tools and equipment to cut or route out patterns and designs in hardened concrete. Usually the concrete is stained first to give it color, so the routed areas look like grout lines.

Efflorescence - A crystalline deposit of salts (usually white in color) that forms on the concrete surface when soluble calcium hydroxides leach from the concrete and combine with carbon dioxide in the atmosphere. On colored concrete, especially darker tones, these white deposits can be particularly unsightly.

Epoxy injection - A method for sealing or repairing cracks in concrete by low-pressure injection of an epoxy adhesive.

Epoxy resins - Organic chemical bonding systems used in the preparation of protective and decorative coatings for concrete, adhesives for injection of cracked concrete, or as binders in epoxy mortars.

Evaporation retarder - A waterborne, spray-applied film that temporarily reduces moisture loss when applied to the surface of freshly placed concrete.

Exposed aggregate - A decorative surface formed by removing the surface mortar from a concrete slab (either by scrubbing, pressure washing, or abrasive blasting) to expose the underlying aggregates. (Also see surface retarder.)

F

Feather edge - To smoothly, seamlessly blend the edge of a topping or repair material into the existing concrete.

Fibers - Tiny filaments made of polypropylene, polyolefin, nylon, polyethylene, polyester, or acrylic used alone or in conjunction with rebar or welded wire mesh to reinforce concrete.

Finishing - Leveling, smoothing, compacting, and otherwise treating the surface of newly placed concrete or concrete overlays to produce the desired appearance and service properties.

Film-forming sealer - A type of sealer that blocks the penetration of water and contaminants by forming a barrier on the concrete surface. May also impart a gloss or sheen, which enhances colored or exposed aggregate concrete. See also membrane.

Flashing (or flash broadcasting) - A technique for applying accent colors of dry-shake hardener to concrete surfaces before stamping. Results in subtle, natural-looking color variations.

Flexural strength - The ability of hardened concrete or an overlay to resist failure in bending.

Float finish - Surface texture (usually rough) obtained by finishing with a bull float or hand float.

Floor polisher - A walk-behind machine used in the production of polished concrete. Most machines are equipped with a planetary drive system, a large primary polishing head (from 17 to 36 inches in diameter) fitted with three or four smaller satellite heads that hold the diamond abrasives. When the machine is operating, the satellite heads rotate in the opposite direction of the primary head to eliminate linear grinding marks in the floor. (Also see diamond grinding, dry polishing, wet polishing).

Fly ash - A supplementary cementitious material (SCM) Fly ash is a byproduct resulting from the combustion of ground or powdered coal; sometimes used as a cement replacement in concrete.

Form liner - Material used to line the interior face of formwork in order to impart a smooth or patterned architectural finish.

Fresno - A large trowel (about 2 to 4 feet in length) used for final finishing after bull floating. Long handles (like those used for bull floats) either clip on or screw into the blade. NOTE: Fresnos should never be used on air-entrained exterior concrete as it seals over the top of the slab trapping bleed water below the surface.

Finishing - The treatment (compacting, leveling, smoothing, etc.) of recently placed or fresh concrete to ensure the planned-for surface.

Flatwork - Mostly flat-surfaced concrete work, including sidewalks, driveways, basements and concrete floors.

G

Gauge rake - A tool with an adjustable depth gauge designed for application of high-build coatings or cementitious toppings at a preset, uniform thickness.

Gravel Mix - A concrete mix that utilizes either pea gravel or larger smooth gravel as its coarse aggregate. This mix is typical for exposed aggregate finishes.

Grade - A building site's (or building's) existing or proposed ground level or elevation. Also used in categorizing building or construction levels, e.g. above grade, on grade, or below grade.

Granulated blast furnace slag – A supplementary cementitious material (SCM) formed when molten blast furnace slag is rapidly chilled. Ground granulated slags are sometimes used in concrete mixtures as a cement replacement to help reduce permeability and improve durability. May also slow setting and extend the working time of the concrete. Mitigates the potential for Alkali-Silica Reaction.

Grinding - A mechanical surface preparation method using rotating abrasive stones or discs to remove thin coatings and mastics or slight flaws and protrusions.

Grout - A mixture of cementitious materials and water, with or without aggregate, proportioned to produce a creamy consistency. Can be purchased preblended in a multitude of colors to define joints and sawcuts in decorative concrete slabs or walls, especially those with stone, brick, or tile patterns

Groover - A tool with a V-shaped bit used to create control joints in plastic concrete.

H

Hand float - A smaller handheld version of the bull float, ranging in length from 12 to 18 inches. Especially useful for floating along the perimeter of forms or to work in tight spots.

Hard-troweled finish - Surface finish obtained by using a trowel with a steel blade for final finishing of concrete. Often used where a smooth, hard, flat surface is desired.

High-pressure water blasting - A process for cleaning or roughening concrete surfaces using a stream of water delivered at high pressure.

High-volume low-pressure (HVLP) sprayer - A spraying device that applies high-solids paints and coatings at low pressure and low velocity, to reduce overspray.

Hopper gun - A gravity-fed system for spray application of coatings or toppings. The material is placed in a hopper attached to a spray gun, which is powered by an air compressor. Often used to apply spray-down systems.

Hover Trowel - A patented lightweight power trowel developed specifically for precision finishing of epoxy, polymer modified, and cementitious overlay systems.

Hydration - The chemical reaction between cement and water that causes concrete or other cement-based materials to harden.

I

Integral color - A coloring agent premixed into fresh concrete or cementitious toppings before placement.

Iron oxide - An inorganic pigment often used to color decorative coatings and toppings.

Isolation Joint - Isolation (or expansion) joints separate or isolate slabs from other parts of the structure such as walls, footings, or columns; and driveways and patios from sidewalks, garage slabs, stairs, light-poles and other points of restraint. They permit independent vertical and horizontal movement between adjoining parts of the structure and help minimize cracking when such movements are restrained.

J

Joint (control, expansion, or isolation) - Formed, sawed, or tooled groove in a concrete slab used to regulate the location of cracking (control joint) or to allow expansion or movement of adjoining structures. In decorative concrete, joints can also double as delineating design elements in a pattern. See: http://www.geigerreadymix.com/portals/0/CIP_Joints_In_Slabs_On_Grade.pdf

Joint filler - A compressible material used to fill a joint to prevent the infiltration of debris.

K

Kerf - A cut in a concrete surface made by a saw or router.

KCMMB Mix - A concrete mix specification designed by the Kansas City Metro Materials Board for longer lasting concrete by creating a mix design requirement of specific materials and hard rock aggregates that can mitigate the effects of salts, deicers, and alkali-silica-reactivity.

Kneeboards - Boards used by concrete finishers to kneel on when hand floating or troweling concrete flatwork.

Knock-down finish - Achieved by applying a decorative topping with a hopper gun and then using a trowel to knock-down the material to produce a smooth or lightly textured surface.

L

Laitance - A thin layer of fine, loosely bonded particles on the surface of fresh concrete, caused by the upward movement of water. Laitance must be removed before application of a decorative coating or topping.

M

Marbleize - To give concrete surfaces the look and gloss of marble, through a combination of color layering and finishing techniques.

Margin trowel - A steel trowel with a small, rectangular flat blade about 5 to 8 inches in length and a short handle. It has multiple uses, including scraping off concrete from finishing tools and applying patching materials.

Masking - Covering select areas of a concrete surface with an adhesive stencil, tape, or other medium before applying a decorative treatment that will affect only the exposed areas.

Material safety data sheet (MSDS) - Information sheets containing pertinent chemical ingredients, product handling and safety guidelines.

Membrane - Formed over a concrete surface to provide protection and enhance color. Typically clear plastic like acrylic, polyurethane or epoxy.

Microtopping - An ultra-thin polymer-based decorative topping, generally less than 1/4-inch total thickness. Typically applied by trowel or squeegee, and given a texture or smooth finish. Pigments can be incorporated into the mix or broadcast onto the surface for a marbleized appearance.

Mil - A measurement equal to 1/1,000 (0.001) inch. Commonly used to denote coating thickness.

Mix design - Specific proportions of ingredients (cement, aggregates, water, and admixtures) used to produce concrete suited for a particular set of job conditions.

Mockup - An architectural concrete sample made using the same materials and methods proposed for an actual project. Often required for quality assurance on large projects, to ensure that architectural requirements and industry tolerances are met. The size should be sufficient to adequately demonstrate all decorative treatments.

Moisture vapor transmission - The migration of moisture vapor to the surface of a concrete slab, caused by vapor pressure differentials in the concrete and the surrounding atmosphere. Can contribute to the failure of impermeable coatings or other floor toppings that do not permit moisture to escape.

N

Neutralize - To return concrete to the proper pH after acid etching, generally by washing the surface with a mixture of water and ammonia or sodium carbonate. Ideal pH is 7.0 (neutral), but a pH range of 6.0-9.0 is acceptable for most coatings. ASTM D 4262, "Standard Test Method for pH of Chemically Cleaned or Etched Concrete Surfaces," covers the procedure for determining the acidity or alkalinity of concrete surfaces prepared by chemical cleaning or etching prior to coating application.

Notched-squeegee - A rubber squeegee with notches or serrations on one or both edges. Used for smooth and consistent spreading of epoxy resin products or other low-viscosity coatings.

O

Opacity - The ability of a coating to hide the color of the underlying surface. See translucent.

Overlay - A bonded layer of material, ranging from 1/4 to 1 inch or more in thickness, placed on existing concrete surfaces to beautify, level, or restore.

P

Patterned Concrete - See Stamped Concrete

Penetrating sealer - A sealer with the ability to penetrate into the concrete surface to increase water repellency. Penetrating sealers chemically react with the concrete preventing water and salt penetrating down through the concrete.

Permeability - The degree to which a membrane or coating will allow the passage or penetration of a liquid or gas.

Pervious Concrete - Pervious concrete is a special type of concrete with a high porosity used for concrete flatwork applications that allows water from precipitation and other sources to pass through it, thereby reducing the runoff from a site and recharging ground water levels.

PH Test - A test performed on the concrete surface to determine the level of acidity or alkalinity. Typically performed prior to applying sealers or coatings.

Pigment - A finely ground natural or synthetic particle adding color and opacity to a coating or topping.

Placing - The physical introduction of the concrete mixture into the final location where it is to harden and cure.

Plastic - A condition of freshly mixed concrete indicating that it is workable and readily moldable.

Plastic shrinkage cracks - Irregular cracks that occur in the surface of fresh concrete soon after it is placed and while it is still plastic.

Plasticizer - Water reducing admixture that allows an increased slump without increasing the water to cement ratio.

Polar Set - A non-Chloride (non-corrosive) accelerating admixture to decrease the set time of concrete in cooler, damp conditions by increasing the rate of hydration.

Polished concrete - A high-gloss finish attained by using special floor polishers fitted with diamond-impregnated abrasive disks (similar to sandpaper) to grind down surfaces to the desired degree of shine and smoothness. The resulting surface is very low-maintenance and can be stained to replicate the look of polished stone.

Polymer modified overlay - A cement-based overlay with polymer resins added to improve performance, wear resistance, and aesthetic qualities. Overlay manufacturers use different types of polymer resins, often blending them to produce proprietary products with unique characteristics. Many of today's decorative overlays use acrylics or vinyl blends because these resins provide excellent bond strength and UV resistance.

Polymer stain - An acrylic-urethane based stain available in a broader palette of colors than acid stains. Very low in volatile organic compounds, with workability characteristics similar to latex paint. Can be applied to concrete surfaces by brush, roller, sponge, cloth, or commercial sprayer.

Pop-out - A pit or crater in the concrete surface, ranging in size from 1/4 inch to several inches in diameter, that results from the fracturing of unsound aggregate particles due to expansion pressure. Usually caused by porous aggregate having a high rate of absorption.

Portland cement - A hydraulic product that sets and hardens when it chemically interacts with water. Made by burning a mixture of limestone and clay or similar materials.

Pozzolan - A siliceous and aluminous material that, in the presence of moisture, chemically reacts with calcium hydroxide to form compounds possessing cementitious properties.

Primer - The first coat of material applied to a concrete surface to improve bonding or adherence of subsequent coats. See also bond coat.

Pump-up sprayer - An airless sprayer often used to apply sealers and liquid release agents.

R

Raveling - The dislodging of aggregate at the edges of joints or scored patterns in concrete, generally caused by sawcutting joints too soon after concrete placement.

Ready-mixed concrete - Concrete that is batched or mixed at a central plant before delivery to the job site for placement.

Rebar (or reinforcing bars) - Ribbed steel bars installed in cast-in-place concrete to provide flexural strength. Rebar come in various diameters and strength grades.

Re-entrant corner - An angle in a concrete slab that points inward. Often vulnerable to cracking, unless a control joint is installed.

Reinforced concrete - Concrete construction that has steel rebar or welded wire mesh embedded in it to provide greater tolerance to tension and flexural stress.

Reflection cracking - The occurrence of cracks in overlays and toppings that coincide with the location of existing cracks in the substrate.

Release agent - A powder or liquid parting agent applied to stamping mats or texturing skins before stamping to keep the mats from sticking to fresh overlay or concrete surfaces.

S

Sack - A quantity of Portland Cement. One sack weighs 94 pounds.

Sack Mix - The amount of sacks of cement in a cubic yard of concrete. Specified when ordering, concrete is typically referred to as 5 sack mix (or 5.5 sack, 6 sack, etc.) The sacks on cement needed in a mix are usually specified in either the plans or the specifications of a project. More sacks = more strength.

Salt finish - A textured, decorative finish obtained by broadcasting rock salt onto fresh concrete and then using a roller or float to press the salt particles into the surface. After the concrete sets, the salt is washed away to reveal a speckled pattern of shallow indentations.

Sandblasting - A method of abrading or profiling a surface with a stream of sand ejected from a nozzle at high speed by compressed air.

Sandblast stenciling - A technique for patterning existing concrete surfaces by applying resilient adhesive stencils followed by sandblasting to lightly remove concrete in only the exposed areas.

Saw-cutting - Using a concrete saw with abrasive blades or disks to cut joints or score patterns into hardened concrete.

Scaling - The flaking or breaking away of a hardened concrete surface, often due to exposure to freezing and thawing. Contrast to spalling, the flaking or chipping of concrete.

Screeding - The operation of forming a surface by the use of a screed or strike-off and screed guides.

Sealer - Solvent- or liquid-based material used to protect and enhance the appearance of decorative concrete.

Seeding - Broadcasting decorative aggregates on the surface of freshly placed concrete or toppings.

Segregation - The separation of the components of wet concrete caused by excessive handling or vibration.

Self-leveling overlay - A flowable, polymer-modified cementitious topping with the ability to self level without troweling. Used to smooth and level existing concrete surfaces. Can also be enhanced by staining, dying, or sawcutting.

Set - The condition reached by concrete when plasticity is lost, usually measured in terms of resistance to penetration or deformation. Initial set refers to concrete that has reached first stiffening. Final set occurs when concrete attains full rigidity.

Setting - The chemical reaction that occurs after the addition of water to a cementitious mixture, resulting in a gradual development of rigidity.

Set retarders - a chemical admixture that slows down the set time of concrete. Used in hot conditions to keep concrete mix from setting too quickly for proper strength gain.

Shotblasting - An abrasive blasting method using round iron shot to clean and profile concrete surfaces.

Skid steer loader

Skim coat - An overlay layer applied very thinly with a squeegee or trowel.

Slag - see Granulated blast furnace slag.

Solvent - Liquid typically used as a carrier for sealers and curing compounds.

Spalling - A breaking away of concrete at joints in floors or slabs. Typically occurs at joints that are installed improperly or don't adequately support the loads applied to them.

Spalling- is caused by water entering concrete and forcing the surface to peel, pop out, or flake off. Concrete spalling is most likely to occur on exterior surfaces that are exposed to freeze and thaw cycles. Causes include: high water cement ratio in the concrete mix, lack of air entrainment, improper finishing, and inadequate curing.

Spray-down system - A decorative overlay applied as a splatter coat or a knock-down finish to a thickness of about 1/8 inch. Often used in conjunction with paper or adhesive stencils. Available pre-colored or can be integrally colored during mixing.

Slump - A measure of consistency of freshly mixed concrete, as determined by the distance the concrete slumps after a molded specimen is removed from an inverted funnel-shaped cone.

Stamped concrete - Concrete flatwork that is patterned with platform tools, stamping mats, or seamless texturing skins to resemble materials such as brick, slate, stone, tile, and wood planking.

Stamped overlay - Similar to conventional stamped concrete, but can be applied to existing concrete. A cementitious topping is applied at a thickness of 1/4 to 3/4 inch and then stamped to mimic brick, slate, and natural stone. Color options include dry-shake color hardeners, colored liquid or powdered release agents, acid stains, dyes, and tinted sealers.

Stamping mats - Rigid or semi-flexible polyurethane tools for imprinting stone, slate, brick, and other patterns in stamped concrete surfaces. Stamping mats usually imprint a shallower pattern than platform tools.

Stenciled concrete - A decorative surface treatment using heavy-duty paper stencils with stone, tile, or brick patterns that are lightly pressed into fresh concrete, followed by the application of dry-shake color hardeners. When the stencils are removed, the uncolored concrete mimics mortar joints. Another technique, for use on existing concrete, is to apply adhesive stencils and then color, etch, or sandblast the surface. (Also see sandblast stenciling.)

Straightedge - A rigid, straight piece of wood or metal used to strike off a concrete surface to proper grade before the floating operation.

Strike off - To level off freshly placed concrete to the correct elevation.

Substrate - An existing concrete surface that receives an overlay, decorative or protective coating, repair procedure, or other resurfacing treatment.

Superplasticizers – High range water reducer that reduces water content by 12 to 13 percent and can be added to concrete with a low-normal slump and water to cement ratio to make a high flowing slump concrete.

Surface retarder - A chemical applied to the surface of newly placed concrete to delay setting of the cement paste so it can be removed easily later by scrubbing or power washing to produce an exposed aggregate finish.

T

Tamper (or pounder) - A handheld impact tool used to firmly press stamping mats or texturing skins into fresh concrete to ensure a complete imprint.

Technical data sheet - Contains important specifications and manufacturer guidelines for product usage. Includes such data as coverage rates, recommended applications, product limitations, surface preparation guidelines, mix ratios and required mixing times, pot life, application procedures, cure times, performance data, and precautions.

Texture roller - A cylindrical tool similar in appearance to a paint roller used to impart a stone-like texture to stenciled concrete. It is rolled over the stencil and the fresh concrete to texture only the exposed surfaces.

Texturing skins - Flexible skins for adding seamless textures to concrete surfaces without leaving deep pattern lines. Generally thinner and more pliable than stamping mats. Often used to texture slab perimeters and vertical faces, such as stair risers. Can also be used to fix blemishes from non-uniform stamping.

Tint - A diluted color wash used to add hints of color to decorative concrete.

Trowel - A flat, broad-bladed steel hand tool used to compact the paste layer at the surface and provide a smooth, flat finish. Also useful for applying topping or repair materials. Available in different shapes (with rounded or square edges) and lengths (ranging from 8 to 24 inches). Smaller trowels are useful for borders, work in restricted areas, or to work in flashing accents of dry-shake color hardener.

Trowel finish - The smooth or lightly textured surface finish obtained by troweling.

V

Vapor barrier - A moisture-impervious material, such as plastic sheeting, placed on the subbase under a concrete slab to help prevent moisture vapor transmission.

Vapor-emission test - An ASTM test used to measure the volume of moisture vapor released from a concrete substrate over time (typically 24 hours). Too much moisture emitted from a slab can affect the performance and bonding of overlays, coatings, and sealers. Moisture vapor test kits are available that include small containers of preweighed, unhydrated calcium chloride.

Vertical stamped concrete - A decorative finish for walls and other vertical surfaces using a lightweight cementitious overlay formulated to be applied at thicknesses of up to 3 inches without sagging. While the overlay is still plastic, it can be stamped or hand carved to produce deep-relief stone or masonry wall textures. After the material dries, acid stains or dyes can be sprayed or sponged onto the surface to give it the multi- Volumetric Mixer

W

Water-cement ratio - The ratio of the amount of water to the amount of cement in a concrete mixture. The key to producing high-quality concrete is to keep the water-cement ratio as low as possible without sacrificing workability.

Water reducer - An admixture that either increases the slump of freshly mixed concrete without increasing water content or maintains workability with a reduced amount of water without affecting the strength.

Welded wire mesh - A woven mesh of wire strands, welded at each intersection, used to reinforce concrete slabs. Also called welded wire fabric.

Wet polishing - A method for polished concrete that uses water to cool the diamond abrasives and eliminate grinding dust. Not as commonly used as dry polishing, because the process creates a tremendous amount of slurry (a soupy mixture of water and cement dust) that must be collected and disposed of.

White cement - A portland cement with a low iron content that hydrates to a white paste. Often used in integrally colored concrete to produce pure, bright color tones, especially pastels.

Workability - The ease with which concrete or other cementitious materials can be mixed, placed, and finished.

Working time - The amount of time available for placing and finishing a cement-based material before it begins to set. Often depends on the ambient temperature and substrate temperature.

X

Xylene - A common solvent. Used as a carrier for solvent based sealers. High in odor and flammability.


Hill and Griffith Customer Service

We're known for our hands on approach. Let us visit your plant and recommend concrete release agents, packerhead concrete form releases, concrete form seasoning, potable water concrete form release, non-petroleum concrete form release, biodegradable concrete form release, rust inhibitors and concrete dissolver products that suit your needs.

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Tags: Concrete Casting Products, concrete release agents, concrete casting supplies, Grifcote, Concrete Terms Glossary

Care and Seasoning of Precast Concrete Metal Forms and Rings

Posted by Chuck Lohre on May 5, 2017 1:19:56 PM

Release agents can contribute to the quality of your product as well as the longevity of your forms. 

Would you ever have thought that you could make money just by walking around? That's the first step (no pun intended) of a maintenance program for your metal forms and rings. Just by taking a look at these expensive pieces of equipment, you can tell whether or not they are getting the attention they need. If they are suffering from neglect, they can cost you later in terms of reduced longevity and deteriorated product quality. It helps to be armed with a little knowledge about form release agents, rust inhibitors and rust preventatives and how they react with metal.

 Precast Concrete Form Seasoning 2.jpg

First, here are some of the basic items needed for form and ring storage and maintenance: 

  • Level area
  • Concrete platform or timber material on which to store them 
  • Covers or tarps for moisture and dust protection (indoor covered storage is ideal but often unavailable)
  • Power washer
  • Putty knife or long-handled ice scrape • Brass wool, scrub pads or other minimally abrasive material for cleaning
  • Electric grinder with wire brush head (not recommended unless absolutely necessary)
  • Release agent (petroleum solvent-based) for long-term form protection

In an ideal world, all of this expensive equipment would be stored indoors in a protected, heated and dry area. Unfortunately this is not the case in the real world, so we need to take care to give our equipment the best possible care with what we have available.

Precast Concrete Form Seasoning 3.jpg

Short-term and long-term storage

For short-term storage, a good quality VOC compliant petroleum solvent-based form release will normally serve our needs. Before the form is put into storage, apply a liberal coating of the form release. If the forms are stored outside, even for a short period of time, a quick walk-by is often necessary to be sure the form release has not washed off from the rain. If any evidence of rust is present, apply another coat of the form release on the forms and rings as quickly as possible.

For long-term storage, a good quality VOC compliant form release will do the job, but as outlined above, recoat with the form release on a regular basis. A biodegradable form release (meeting the EPA definition of biodegradability, but not a water-based material) is preferred, as over-application is desired and some of the material will end up on the ground,

The second alternative for long-term storage is a rust inhibitor. Rust inhibitors should have the capacity to displace the mechanically held water on the surface of the form. The form also needs to be protected with a plastic cover or inverted so that rain and snow do not wear the rust inhibitor away. With rust inhibitors, the form can generally be brought back into production with a minimum of labor required to remove the inhibitor. If you are using a water-based form release, it is best to apply a rust inhibitor or rust preventative as quickly as possible, as the residual water will cause rusting immediately. 

The third alternative is a rust preventative. These are typically epoxy­ based materials that can be compared to a layer of paint. While rust preventatives generally do a good job in protecting the forms, they are fairly labor intensive in application and should be removed before bringing the forms and rings back into production. Grinding is usually necessary to remove the 􀌉ust preventative, which in turn dest􀌤oys the "seasoning" of the for.m

When storing equipment, it should be stored in such a fashion that it can be put back into production without having to spend time adjusting or repairing. Rings (pallets and headers) should be stored in flat racks in a stack and, if possible, on pallets.

Precast Concrete Form Seasoning 1.jpg

Seasoning 

Reactive form release agents, the most commonly used release agents in precast and pipe production, typically contain fatty acids. Fatty acids are mild acids composed of animal fats and vegetable oils. Of course, there are a very great number of possible combinations of animal fats and vegetable oils, and not all combinations will serve as "good" reactive form release agents.

The reactive portion of the form release agent serves two initially important functions. First, fatty adds have a natural affinity for metal. This includes gray, ductile and malleable iron, brass, bronze, aluminum and mild steel. Fatty acids react with metal to form a protective barrier, which is a coating of metallic oleate. This process is known as seasoning. This protective layer prevents further application of fatty acids from migrating to the metal of the form and allows the fatty acid to remain on the surface of the form to react with the free lime on the surface of the casting. 

Try using this analogy on your production workers to help them understand some of the concepts of seasoning:

A fisherman always has his "favorite" frying pan, there is no way that he would ever let that frying pan be put in water and scrubbed clean with a scouring pad. Why? Because it would remove the seasoning that is part of the pan. If he has to buy a new pan, what is the first thing he does? He gets some lard or vegetable oil (both are simple examples of fatty acids), puts it in the pan and places the pan in the oven at a high temperature for an extended period of time. Why? So the pan can become seasoned.

This same seasoning holds true for your forms and pallets, When concrete is poured into the form, the reactive portion of the form release (the fatty acid) reacts with the free lime on the surface of the concrete to form a metallic soap. This reaction is called neutralization. As fatty acids (typically a pH of 6.8) react with the free lime on the surface of the concrete (typically a pH of 11.5), they neutralize one another and create the metallic soap, a reaction known as saponification.

This soap, then, also serves two purposes. First, it enhances the easy separation of the form from the castings. Second, as it is a soap, it allows free air to rise more easily on the vertical surfaces of the castings, resulting in fewer surface defects.

Once this metallic oleate layer is created on the metal form, any grinding or surface abrasiveness, including welding to repair a form or grinding with wire brushes, will destroy the protective layer. The next time a reactive form release is applied, the fatty acid will react with the form, leaving nothing to react with the free lime. It is very important to minimize grinding on forms, and usually nothing finer than a putty knife or an ice scraper should be used to remove splatter or "stickers." In the case of sticker, there is a reason that this occurs, and normally an application of a seasoning agent to this small area will help prevent future sticking and buildup.

Seasoning of forms is a very basic requirement to help minimize the amount of labor involved when forms are stripped or pipes are tipped out. If forms, pallets and headers are properly maintained, labor cost and better looking castings are the end result.

Precast Concrete Form Seasoning 4.jpg

Forms in storage, new forms, pallets and headers

New forms, pallets and headers will frequently arrive with a protective coating on them to help prevent rusting in transit or until the forms are sold and delivered. This protective coating can be allowed to wear off, but at that point it is allowing raw metal to be exposed. While the first few pours might be satisfactory, now that raw metal is exposed, the reactive portion of the form release agent will now start to react with the raw metal, leaving nothing to react with the free lime and form the metallic soap. An alternative is to remove the protective coating with solvents or grinding and apply a seasoning agent, allowing it to set for a minimum of four hours. A 24-hour period is better, as it allows more seasoning to take place. Also, forms that are exposed to the sun will season more quickly as higher temperatures increase the reactivity with the metal forms and rings.

Forms that have been in storage and have rusted also need to be reseasoned. Rust is nothing more than oxidized metal, and when rusting occurs, the metallic oleate barrier has been destroyed. Casting can be done without removing the rust, but again, once the raw metal is exposed, the fatty acid will react with the raw metal until the form is seasoned. The rust stain will also transfer to the casting. An alternative is to grind down the form/pallet/headers, apply a seasoning agent and allow time for the reaction to take place to allow the metallic oleate to form.

The old saying of "An ounce of prevention is worth a pound of cure" holds true to maintaining your forms, pallets and headers by getting them seasoned and keeping them seasoned. A little attention today will save a lot of grief tomorrow.

Proper seasoning of precast concrete metal forms and treatment of this very costly equipment with the care it deserves will enable you to be more competitive in the marketplace and be a better steward of our environment. mc

Published in Manufactured Concrete Jan/Feb 2007 by the National Precast Concrete Association. Archived here.

By Bob Waterloo, the technical sales manager of concrete release agents for The Hill and Griffith Co. in Greenwood, Ind,


Hill and Griffith Customer Service

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Tags: Concrete Casting Products, concrete release agents, concrete casting supplies, bugholes, Seasoning of Precast Concrete Metal Forms, Grifcote

Construction Forming System Precast Concrete Release Agent Application

Posted by Chuck Lohre on May 1, 2017 5:42:12 PM

Care and Seasoning of Metal Forms and Rings

Would you ever have thought that you could make money just by walking around? That’s the first step (no pun intended) of a maintenance program for your metal forms and rings. Just by taking a look at these expensive pieces of equipment, you can tell whether or not they are getting the attention they need. If they are suffering from neglect, they can cost you later in terms of reduced longevity and deteriorated product quality. It helps to be armed with a little knowledge about form release agents, rust inhibitors and rust preventatives and how they react with metal. 

Read the full article here, by Bob Waterloo Technical Sales Manager of concrete release agents for The Hill and Griffith Co. in Greenwood, Ind.

Precast Concrete Release Agent Video 1.jpg 

 

(Video and image from Precise Forms, "Precise Forms is a family owned and operated business with sights set for aggressive contractors and their needs. Precise Forms manufactures standard and custom aluminum forming systems for foundations, basements, concrete homes, apartment complexes, precast, commercial structures, and agricultural buildings both nationally and internationally. The Dominator Forming System sgown is a taper tie system that can be used to create concrete homes, concrete commercial projects, or concrete precast boxes. The system can be hand set or ganged allowing for entire sections to be moved at one time saving both time and money. The Dominator creates straight, smooth walls with little to no deflection when properly braced.")


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We're known for our hands on approach. Let us visit your plant and recommend concrete release agents, packerhead concrete form releases, concrete form seasoning, potable water concrete form release, non-petroleum concrete form release, biodegradable concrete form release, rust inhibitors and concrete dissolver products that suit your needs.

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Grifcote® Premium Concrete Dissolver

Posted by Chuck Lohre on Apr 20, 2017 11:05:27 AM

GRIFCOTE® Premium Dissolver is a proprietary blend of materials that promote the removal of hardened concrete.

The reaction of GRIFCOTE® Premium Concrete Dissolver with the previously deposited concrete on the surface of a metallic surface will facilitate the removal of this material.

Hollow precast concrete wall production showing concrete release agent on form.jpg 
(Hollow precast concrete wall production showing concrete release agent on form. Image from Tachydomi Sa video.)


(Video and photos show the construction stages of hollow precast wall production in the Tachydomi SA factory. Learn more.)


Application

The recommended method for the application of the GRIFCOTE® Premium Dissolver is by utilizing a hard bristle brush, mechanical sprayer or any other compatible spray method which applies a fine mist or spray covering all of the areas that require treatment.

For optimum performance of GRIFCOTE® Premium Dissolver saturate the area of the hardened concrete and allow GRIFCOTE® Premium Dissolver to penetrate the surface for 10 to 20 minutes. After the GRIFCOTE® Premium Dissolver contacts the hardened concrete the surface will turn white and then darken. Re-treat the surface if a white residue appears on the area where the concrete remains. Re-apply surface until concrete has turned to a softened material (mush). On areas of the metal surface where a thick buildup is observed, repeat the application of the GRIFCOTE® Premium Dissolver and repeat the cleaning process until the concrete on the metal surface has softened and turned to “mush”.

**Application rate will vary depending on metal surface and application methods.

Technical Data:

Color  Light Orange
Weight per Gallon 8.1 lbs/gal
Flash Point N/A (P.M.C.C.)
Viscosity >1 @ 40° C
Specific Gravity   0.97
Density 8.1 lbs/gal
PH 1.8

A Material Safety Data Sheet should be reviewed for safety precautions prior to application.


Hollow precast concrete wall production 2.jpg
(Hollow precast concrete wall production showing cured side being set on wet side. Image from Tachydomi Sa video.)

Hollow precast concrete wall production 3.jpg
(Hollow precast concrete wall production showing finished wall being placed in storage. Image from Tachydomi Sa video.)


Hill and Griffith Customer Service

We're known for our hands on approach. Let us visit your plant and recommend concrete release agents, packerhead concrete form releases, concrete form seasoning, potable water concrete form release, non-petroleum concrete form release, biodegradable concrete form release, rust inhibitors and concrete dissolver products that suit your needs.

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Tags: Concrete Casting Products, concrete dissolver, concrete casting supplies, precast concrete, Gricote, precast concrete dissolver

Application of Precast Concrete Form Oil

Posted by Chuck Lohre on Apr 14, 2017 10:03:48 AM

From the National Precast Concrete Association - Precast Learning Lab

Published on Feb 24, 2017 - Learn how to properly apply form oil at your precast concrete plant.
 

How To - Application of Precast Concrete Form Oil

Spokesperson, "So Lynn, Why is form release application such a critical step in the production process?"
 
Lynn, "It's so critical because it helps you in stripping product out of the form, you get a better overall finished product and it really preserves the life of your mold. As you can see behind me, we have a mold that was stripped earlier today. Before we talk about applying release agent, it’s important to know…"
 

Application of Precast Concrete Form Oil - 1.jpg

NPCA members can view the full video - part of the Precast Learning Lab series - on myNPCA. http://portal.precast.org

Application of Precast Concrete Form Oil - 2.jpg

Application of Precast Concrete Form Oil - 3.jpg

Application of Precast Concrete Form Oil - 4.jpg


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Self-Consolidating Offers Concrete Bug Hole Solution

Posted by Chuck Lohre on Apr 6, 2017 10:38:00 AM

What you do affects the surface aesthetics of self-consolidating concrete

By

concrete-bug-hole-solution.jpgSelf-consolidating concrete (SCC) has been used to produce many aesthetically critical projects since its development nearly 20 years ago. Although mixes of various levels of strength and durability can be designed to generate smooth, defect-free surfaces, this does not ensure that the finished structure will be unflawed.

Two outside influences can greatly affect the appearance of concrete. The first is forming materials—the most popular are steel and plywood. The second factor is release agents. Different types and brands of release agents (form oils) give varying degrees of surface defect. The method of application of these agents also plays a part in the final product appearance.

(This week's concrete bug hole solution post comes from a December 21, 2005 article in Concrete Construction Magazine.)



What you do affects the surface aesthetics of self-consolidating concrete

SCC with an appropriate release agent yields defect-free surfaces.

In 2003 we launched a study to evaluate the effects of form conditions on the finished surface of SCC. Two SCC mixes were developed that could produce a defect-free formed surface. One design was a “high fines” SCC (Mix 1 in the table), and the other used a stabilizer, or viscosity modifying admixture (VMA).

Both were well-designed, stable mixes, verified by casting and testing samples. Both mixes also attained 5% ±1.5% entrained air content that met the industry accepted criteria for specific surface and spacing factors, exhibiting a very stable air matrix.

Note that entrained air content does not affect the presence of bug holes; entrapped air—air bubbles too large to benefit the concrete—is what clings to the formwork. Entrapped air can be generated during the casting process (most bug holes appear near where a form is filled), or large air bubbles can be generated and trapped in the concrete because of the superplasticizer. The new-generation polycarboxylate-based high-range water-reducing (HRWR) admixtures often contain significant amounts of defoamer to reduce air entrapment, but this can wreak havoc on the entrained air matrix.

Forms

Wood forms and metal forms will show significant differences in surface defects. Wood forms tend to produce fewer bug holes than metal because wood forms soak up excess release agent that has been hastily applied. Any small amount of extra oil on a steel form will react with the concrete mix and create small bug holes, perhaps better termed “pinholes.” Therefore, proper application is absolutely necessary. Steel forms require more attention to ensure a clean, smooth surface. Any defect on the form will create a blemish on the concrete surface.

A form's cleanliness and smoothness greatly affect the appearance of the concrete surface. This simple, logical truth cannot be overstated when dealing with SCC.

concrete-bug-hole-solution

Forms should be as smooth as possible to allow entrapped air to move easily upward along the form system; they must be kept free of paste buildup and laitance, which prevent air and water pockets from traveling to the concrete surface. In our study, as paste built up on each form with subsequent castings, the concrete surface appeared worse. Scratches or gouges will hold air against the surface of the concrete. Any steel forms pitted with rust will cause blemishes, which at times produce more bug holes than are noticeable with vibrated conventional concrete. We also noticed that when the form skin had a lower temperature than the SCC, air voids smaller than usual were present. That occurred at approximately a 25° F temperature difference.

Whenever you grind a “seasoned” steel form, you remove the protective barrier previously produced by the reactive form release agent. Rusted forms have negated the barrier that was in place. Once the form is ground, raw metal is exposed. The reactive portion of the form release agent, typically a fatty acid, has a natural affinity for metal. The fatty acid attacks the raw metal and forms metallic oleate, which acts as a protective coating. Subsequent applications of reactive form release agents are prevented from getting to the metal by the protective layer of metallic oleate, allowing the reactive portion of the form release to be available to react with the free lime on the surface of the concrete. This reaction forms a chemically inert metallic soap, which gives good release and allows free air to rise more easily to the surface on vertical walls. Until the form is seasoned, or the protective barrier is formed, the reactive portion combines with the metal, leaving nothing to react with the free lime. The steel forms used in this study were seasoned after cleaning and before further castings took place. That aided the finish somewhat but the pits left in the forming material by the rusting process trapped air voids, creating bug holes.


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Form Seasoning Concrete Release Agent

Posted by Chuck Lohre on Mar 30, 2017 4:06:49 PM

Concrete Release Agent that also acts as a Form Seasoning 

Form Seasoning-Concrete-Release-Agent.jpgGrifcote CC-150-VOC is widely used to season forms for optimal concrete release.

Spraying form release agents on mixers and equipment reduces labor and cleanup at the end of the day eliminating concrete adhering to the equipment.

The Hill and Griffith Company also works closely with pipe and form equipment manufactures to provide optimum concrete release characteristics with their equipment.

Convenient and reliable

Gifcote concrete release products are non-staining and ready to use with no mixing needed and offer many unique features to improve concrete separation from forms, pallets and molds.

All Grifcote products are available in 55 gallon drums, 330- gallon totes or bulk tank wagons.

All Grifcote Form Seasoning Concrete Release Agent products have indefinite freeze/thaw cycles. You don’t need to worry about Grifcote degradation due to temperature changes.


Hill and Griffith Customer Service

We're known for our hands on approach. Let us visit your plant and recommend concrete release agents, packerhead concrete form releases, concrete form seasoning, potable water concrete form release, non-petroleum concrete form release, biodegradable concrete form release, rust inhibitors and concrete dissolver products that suit your needs.

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Tags: Concrete Casting Products, concrete casting supplies, precast concrete, Gricote, concrete-release-agent, form seasoning, Form Seasoning Concrete Release Agent

Proper Application of Precast Concrete Form Release Agents

Posted by Chuck Lohre on Mar 23, 2017 9:31:59 AM

(This week's Concrete Casting News post is a review of a National Precast Concrete Association Tech Note publication. You can read the entire document here, "Proper Application of Precast Concrete Form Release Agents." )

Proper Application of Precast Concrete Form Release Agents.jpgRelease agents, when properly used, aid in the stripping process, assist in producing sound defect-free concrete surfaces, simplify form cleaning and increase the working life of quality form surfaces. There are two main categories of form release agents:

  • Barrier – those that provide a physical barrier between the form and the concrete (such as petroleum-based products, soaps, synthetic resins, waxes)

  • Reactive – those containing fatty acids or other ingredients that react with the free lime in fresh concrete to produce a metallic soap interface between the form and the concrete (such as proprietary products and vegetable oils that are typically found in petroleum-based carrying agent products).

Concrete Form Release Application photo.jpgRelease agents should be applied to a clean form before the reinforcement has been placed to reduce the likelihood of inadvertently applying it to the reinforcement. If the release agent does come in contact with reinforcement it should be wiped clean before placing the concrete. When applying a release agent it is best to follow the manufacturer’s instructions. When too much form release is used, it is not only wasteful and inefficient, but it leads to a number of other associated problems with the finished product.

He who holds the wand determines the amount of material being applied, so proper training is crucial. As a rule of thumb, remember: Less is better. The amount needed to affectively coat a form is only about 0.005 inches thick. The actual cover thickness will depend on the application method and viscosity of the product, which is related to the ambient temperature. Typically, the colder it is in the plant, the thicker, or more viscous, the release agent will be. The warmer it is the plant, the thinner, or less viscous, it will be. Different measures can be taken during the application process to account for changes in material temperature (viscosity) throughout the year.

SPRAYING

Spraying is probably the most efficient and common method for applying release agents. Keep the wand moving when applying form release. Broad nozzle/flat spray tips have been found to give the thinnest and most uniform cover. It should be noted that as the temperature drops and viscosity increases, the spraying pressure should be increased and the nozzle orifice size reduced. As temperatures rise, reduce pressure and increase nozzle size. It is a good practice to soak or mop up any puddles that may have formed at the bottom of the form Remember: Less is better. Only through experience and training will you learn what works best for your plant’s production line.

CAUTION: Fatty acids will react with brass, bronze, aluminum, grey ductile and malleable iron and mild steel, as well as some petroleum-based products used for making blockouts and other embedded items. It is best to use stainless steel, nickel or plastic for your spraying systems and to test for possible reaction of embedded materials prior to full implementation.

SWABBING AND PAINTING

Swabbing and painting by hand is an acceptable application method, with the benefit of eliminating the majority of airborne particulate. On the negative side, applications tend to be thicker than necessary, leading to wasted material and the potential for additional problems. WIPING Wiping is often the method of choice for architectural precasters concerned with a blemish-free surface. Wiping on release agents with a sponge or rag will normally result in the thinnest coating, but it is very labor intensive.

DIPPING

Automated dipping systems are fast, labor efficient and ensure complete coverage. Excess material will usually drip back into a holding tank, reducing material waste. The application coat is often thicker than necessary, however, again creating the potential for future problems.

(You can read the entire document here, "Proper Application of Precast Concrete Form Release Agents." )


Hill and Griffith Customer Service

We're known for our hands on approach. Let us visit your plant and recommend concrete release agents, packerhead concrete form releases, concrete form seasoning, potable water concrete form release, non-petroleum concrete form release, biodegradable concrete form release, rust inhibitors and concrete dissolver products that suit your needs.

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We are pleased to provide samples in quantities large enough to allow you to "try before you buy."
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Tags: Concrete Casting Products, concrete casting supplies, precast concrete, Gricote, concrete-release-agent

Choosing wrong release agent creates concrete bug holes

Posted by Chuck Lohre on Mar 17, 2017 4:45:39 PM

(This week's Concrete Casting News post comes from a YouTube video that illustrates how the selection of concrete form release affects the production of concrete bug holes. Many questions in the comment section ask what the two release agents were. We can guarantee that all Hill and Griffith products are engineered to reduce the formation of bug holes by using reactive fatty acid/methyl esters that react with free lime on the surface of the casting.)

From Paolo Redaelli, "Effects of two releasing agents of the surface of a properly vibrated concrete. Please note the one on the left having a perfect surface after very few seconds while the one on the right keeps forming bubbles of air."

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Hill and Griffith Customer Service

We're known for our hands on approach. Let us visit your plant and recommend concrete release agents, packerhead concrete form releases, concrete form seasoning, potable water concrete form release, non-petroleum concrete form release, biodegradable concrete form release, rust inhibitors and concrete dissolver products that suit your needs.

Hill and Griffith Samples

Product Samples

We are pleased to provide samples in quantities large enough to allow you to "try before you buy."
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Hill and Griffith Customer Service

Technical Services & Support

On-site casting defect investigations, product testing, machine start-ups and much more. Also, lab facilities are available to provide testing upon request.
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 Bulletins and Technical Papers for Concrete Casting Products

Tags: Concrete Casting Products, concrete casting supplies, precast concrete, Grifcote FR 50 Concrete Form Release, Bio Gold Concrete Form Release, Gricote, concrete-release-agent, concrete bug holes