COMPOSITE FABRICATING BASIC GUIDELINES

By resolute definition, a fabricated COMPOSITE material is a manufactured collection of two or more ingredients or products intentionally combined to form a new homogeneous material that is defined by its performance that should uniquely greater than the sum of its individual parts. This method is also defined as a SYNERGISTIC COMPOSITION.

 

COMPOSITE MATERIAL COMPOSITION

REINFORCING FABRIC       &     IMPREGNATING RESIN

 PLUS  

 

'ENGINEERED PROCESS'

EQUALS

COMPOSITE LAMINATE WITH THE BEST WEIGHT TO STRENGTH PERFORMANCE

 

With respect to the raw materials selection -fabric and resin, the fabricating process and the and curing and test validation of composite part, these aspects must be carefully considered and in the engineering phase of the composite.

Step One: Fabric Selection

TYPES OF FABRIC WEAVE STYLE AND SURFACE FINISHING

FOR RESIN TYPE COMPATIBILITY 

Fabrics are generally considered ”balanced” if the breaking strength is within 15% warp to fill and are best in bias applications on lightweight structures. “Unbalanced” fabrics are excellent when a greater load is required one direction and a lesser load in the perpendicular direction. 

• Tow: The bundle of individual carbon filaments used to weave carbon fabric. 50k tow means there are 48-50,000 carbon filaments in the tow. Smaller tow i.e. 12k, 6k, 3k and 1k are obtained by dividing the 50k tow into smaller bundles.
• Thread Count: The number of threads (tow in carbon and yarn in Aramid) per inch. The first number will be the warp count and the second will be the fill count. 
• Fill: The threads that run the width of the roll or bolt and perpendicular to the warp threads. 
• Warp: The threads that run the length of the roll or bolt and perpendicular to the fill threads. 
• Finish: The chemical treatment to fiberglass making it compatible with resin systems, therefore improving the bond between the fiber and the resin. Finishing fiberglass typically decreases the fiber strength by as much as 50%. Both Silane and Volan finishes are epoxy compatible. Historically, Volan has been considered a softer finish for a more pliable fabric, but recent advances have yielded some excellent soft Silane finishes.
• Thickness: Measured in fractions of an inch. The thicker the fabric the more resin required to fill the weave to obtain a surface-smooth finished part.

Weaves:

• Plain weave means the warp and fill threads cross alternately. This is the most common weave.
• 4 Harness (4 HS Satin or crowfoot) weave means the fill thread floats over three warp threads, then under one warp thread. This weave is more pliable than the plain weave, therefore conforms to complex curves more easily.
• 8 Harness (8 HS Satin) weave means the fill thread floats over seven warp threads, then under one warp thread. This weave is the most pliable of the standard fiberglass weaves.
• 2 x 2 Twill weave means the fill thread floats over two warp threads, then fewer than two warp threads. This weave is found most commonly in carbon fabrics and is more pliable than plain weave.

Most fabrics are stronger in the warp than the fill because higher tension is placed on the warp fiber keeping it straighter during the weaving process. Rare exceptions occur when a larger, therefore stronger thread is used in the fill direction than the warp direction. 

PLAIN WEAVE Is a very simple weave pattern and the most common style. The warp and fill yarns are interlaced over and under each other in alternating fashion. Plain weave provides good stability, porosity and the least yarn slippage for a given yarn count.	8 HARNESS SATIN WEAVE The eight-harness satin is similar to the four-harness satin except that one filling yarn floats over seven warp yarns and under one. This is a very pliable weave and is used for forming over curved surfaces.	4 HARNESS SATIN WEAVE The four-harness satin weave is more pliable than the plain weave and is easier to conform to curved surfaces typical in reinforced plastics. In this weave pattern, there is a three by one interfacing where a filling yarn floats over three warp yarns and under one.	2x2 TWILL WEAVE Twill weave is more pliable than the plain weave and has better drivability while maintaining more fabric stability than a four or eight harness satin weave. The weave pattern is characterized by a diagonal rib created by one warp yarn floating over at least two filling yarns.

 SATIN WEAVE TYPE CONFORMITY UNTO CURVED SHAPES

Plain Weaves, Bi-axial, Unidirectional Styles For Directional High Strength Parts Use this weave style cloth when high strength parts are desired.It is ideal for reinforcement, mold making, aircraft and auto parts tooling, marine, and other composite lightweight applications.

7544 Fiberglass - YouTube

 FIBERGLASS FINISHING FOR RESIN COMPATIBILITY

All of the fiberglass fabrics is woven By HEXCEL COMPOSITES, a leading manufacturer of composite materials engineered for high-performance applications in marine, aerospace for commercial and military, automotive, sporting goods and other application-critical performance. These fabrics are 100% epoxy-compatible and will yield the best mechanical properties when properly fabricated. 

Finishing Cross Reference And Resin Type Compatibility 

RESIN COMPATIBILITY	Burlington Industries	Clark Schwebel	J.P Stevens	Uniglass Industries
Epoxy, Polyester	VOLAN A	VOLAN A	VOLAN A	VOLAN A
Epoxy, Polyester	I-550	CS-550	S-550	UM-550
Phenolic, Melamine	I-588	A1100	A1100	A1100
Epoxy, Polyimide	I-589	Z6040	S-920	UM-675
Epoxy	I-399	CS-272A	S-935	UM-702
Epoxy		CS-307		UM-718
Epoxy		CS-344		UM-724
Silicone	112	112		n-pH (neutral pH)

AVAILABLE FIBERGLASS, CARBON FIBER, AND KEVLAR FABRICS

HEXCEL 120 1.5-OUNCE FIBERGLASS PLAIN WEAVE 5 YARDS	https://www.ebay.com/itm/222623985867
HEXCEL 120 1.5-OUNCE FIBERGLASS PLAIN WEAVE 10 YARDS	https://www.ebay.com/itm/311946399588
HEXCEL 7532 7-OUNCE FIBERGLASS PLAIN WEAVE 5 YARDS	https://www.ebay.com/itm/222624899999
HEXCEL 7500 10 OUNCE FIBERGLASS PLAIN WEAVE 3 YARDS	https://www.ebay.com/itm/222624968104
HEXCEL 7500 10 OUNCE FIBERGLASS PLAIN WEAVE 5 YARDS	https://www.ebay.com/itm/311946460378
HEXCEL 3582 14 OUNCE FIBERGLASS SATIN WEAVE 5 YARDS	https://www.ebay.com/itm/312023587290
HEXCEL 3582 14 OUNCE FIBERGLASS SATIN WEAVE 10 YARDS	https://www.ebay.com/itm/222753506374
HEXCEL 1584 26 OUNCE FIBERGLASS SATIN WEAVE 3 YARDS	https://www.ebay.com/itm/311947365010
HEXCEL 1584 26 OUNCE FIBERGLASS SATIN WEAVE 5 YARDS	https://www.ebay.com/itm/222629157570
FIBERGLASS 45+/45- DOUBLE BIAS 3 YARDS	https://www.ebay.com/itm/311947299244
CARBON FIBER FABRIC 3K 2x2 TWILL WEAVE 6 OZ. 3 YARDS	https://www.ebay.com/itm/311947275431
CARBON FIBER FABRIC 3K PLAIN WEAVE 6 OZ 3 YARDS	https://www.ebay.com/itm /311947292012
KEVLAR 49 HEXCEL 351 PLAIN WEAVE FABRIC 2.2 OZ	https://www.ebay.com/itm/222623951106

Step Two: Choose The Best Epoxy Resin System For The ApplicationThe epoxy resin used in fabricating a laminate will dictate how the FRP will perform when load or pressure is implied on the part.To choose the proper resin system, consider the following factors that is crucial to a laminate's performance.SIZE AND CONFIGURATION OF THE PART(NUMBER OF PLIES  AND CONTOURED, FLAT OR PROFILED)CONSOLIDATING FORCE(FREE STANDING DRY OR HAND LAY-UP, VACUUM BAG OR PLATEN PRESS CURING)CURING CAPABILITIES(HEAT CURED OR ROOM TEMPERATURE CURED)LOAD PARAMETERS

(SHEARING FORCE, TORSIONAL AND DIRECTIONAL LOAD, BEAM STRENGTH)

ENVIRONMENTAL EXPOSURE

The principal role of the resin is to bind the fabric into a homogeneous rigid substrate

(OPERATING TEMPERATURE, AMBIENT CONDITIONS, CHEMICAL EXPOSURE, CYCLIC FORCE LOADING)

MATERIAL AND PRODUCTION COST

(BUYING IN BULK WILL ALWAYS PROVIDE THE BEST OVERALL COSTS)

These factors will dictate the design and the composition of the part and must be carefully considered during the design and engineering phase of the fabrication.

TOP SELLING IMPREGNATING RESIN SYSTEM 

 MAX BOND LOW VISCOSITY A/B

Marine Grade Boat Building Resin System, Fiberglassing/Impregnating, Water Resistance, Cured Structural Strength

MAX BOND LOW VISCOSITY 32-Ounce kit	https://www.ebay.com/itm/311947109148
MAX BOND LOW VISCOSITY 64-Ounce Kit	https://www.ebay.com/itm/311947125422
MAX BOND LOW VISCOSITY 1-Gallon Kit	https://www.ebay.com/itm/311947117608
MAX BOND LOW VISCOSITY 2-Gallon kit	https://www.ebay.com/itm/311946370391
MAX BOND LOW VISCOSITY 10-Gallon Kit	https://www.ebay.com/itm/222624960548

 MAX 1618 A/B

Crystal Clear, High Strength, Lowest Viscosity (Thin), Durability & Toughness, Excellent Wood Working Resin

MAX 1618 A/B 48-Ounce Kit	https://www.ebay.com/itm/222627258390
MAX 1618 A/B 3/4-Gallon Kit	https://www.ebay.com/itm/222625113128
MAX 1618 A/B 3/4-Gallon Kit	https://www.ebay.com/itm/222627258390
MAX 1618 A/B 1.5-Gallon Kit	https://www.ebay.com/itm/311946441558

 MAX CLR A/B

Water Clear Transparency, Chemical Resistance, FDA Compliant For Food Contact, High Impact, Low Viscosity

MAX CLR A/B 24-Ounce Kit	https://www.ebay.com/itm/222623963194
MAX CLR A/B 48-Ounce Kit	https://www.ebay.com/itm/311947320101
MAX CLR A/B 96-Ounce Kit	https://www.ebay.com/itm/222625329068
MAX CLR A/B 96-Ounce Kit	https://www.ebay.com/itm/222625338230
MAX CLR A/B 1.5-Gallon Kit	https://www.ebay.com/itm/222626972426

MAX GRE A/B

GASOLINE RESISTANT EPOXY RESIN 

Resistant To Gasoline/E85 Blend, Acids & Bases, Sealing, Coating, Impregnating Resin

MAX GRE A/B 48-Ounce Kit	https://www.ebay.com/itm/311946473553
MAX GRE A/B 96-Ounce Kit	https://www.ebay.com/itm/311947247402

 MAX HTE A/B

HIGH-TEMPERATURE EPOXY

Heat Cured Resin System For Temperature Resistant Bonding, Electronic Potting, Coating, Bonding

MAX HTE A/B 80-Ounce Kit	https://www.ebay.com/itm/222624247814
MAX HTE A/B 40-Ounce Kit	https://www.ebay.com/itm/222624236832

Step Three:

Proper Lay-Up Technique -Putting It All Together

Pre-lay-up notes

• Lay out the fabric and pre-cut to size and set aside
• Avoid distorting the weave pattern as much as possible
• For fiberglass molding, ensure the mold is clean and adequate mold release is used
• View our video presentation above "MAX EPOXY RESIN MIXING TECHNIQUE"
• Mix the resin only when all needed materials and implements needed are ready and within reach

Mix the proper amount of resin needed and be accurate proportioning the resin and curing agent. Adding more curing agent than the recommended mix ratio will not promote a faster cure. Over saturation or starving the fiberglass or any composite fabric will yield poor mechanical performance. When mechanical load or pressure is applied to the composite laminate, the physical strength of the fabric should bear the stress and not the resin. If the laminate is over saturated with the resin it will most likely to fracture or shatter instead of rebounding and resist damage.

Don’t how much resin to use to go with the fiberglass?

A good rule of thumb is to maintain a minimum of 30 to 35% resin content by weight, this is the optimum ratio used in high-performance prepreg (or pre-impregnated fabrics) typically used in aerospace and high-performance structural application.

For general hand lay-ups, calculate using 60% fabric weight to 40% resin weight as a safety factor. This will ensure that the fabricated laminate will be below 40% resin content depending on the waste factor accrued during fabrication.

Place the entire pre-cut fiberglass to be used on a digital scale to determine the fabric to resin weight ratio. Measuring by weight will ensure accurate composite fabrication and repeatability, rather than using OSY data.

THE USE OF A WEIGHING SCALE IS HIGHLY RECOMMENDED 

Purchase this scale with any of our product offering and the shipping cost of the scale is free. 

https://www.ebay.com/itm/222630300203

A good rule of thumb is to maintain a minimum of 30 to 35% resin content by weight, this is the optimum ratio used in high-performance prepreg (or pre-impregnated fabrics) typically used in aerospace and high-performance structural application. For general hand lay-ups, calculate using 60% fabric weight to 40% resin weight as a safety factor. This will ensure that the fabricated laminate will be below 40% resin content depending on the waste factor accrued during fabrication.

Place the entire pre-cut fiberglass to be used on a digital scale to determine the fabric to resin weight ratio. Measuring by weight will ensure accurate composite fabrication and repeatability, rather than using OSY data.

Typical fabric weight regardless of weave pattern

1 ounce per square yard is equal to 28.35 grams

1 square yard equals to 1296 square inches (36 inches x 36 inches)

FOR EXAMPLE

1 yard of 8-ounces per square yard (OSY) fabric weighs 226 grams

1 yard of 10-ounces per square yard (OSY) fabric weighs 283 grams

Ounces per square yard or OSY is also known as aerial weight, which is the most common unit of measurement for composite fabrics. To determine how much resin is needed to adequately impregnate the fiberglass, use the following equation:

(Total Weight of Fabric divided by 60%)X( 40%)= weight of mixed resin needed

OR

fw= fabric weight

rc= target resin content

rn=resin needed

MASTER EQUATION

(fw/60%)x(40%)=rn

FOR EXAMPLE

1 SQUARE YARD OF 8-OSY FIBERGLASS FABRIC WEIGHS 226 GRAMS

(226 grams of dry fiberglass / 60%) X 40% = 150.66 grams of resin needed

So for every square yard of 8-ounce fabric, it will need 150.66 grams of mixed resin.

Computing For Resin And Curing Agent Amount

150.66 grams of resin needed

MIX RATIO OF RESIN SYSTEM IS 2:1 OR

50 PHR (per hundred resin)

2 = 66.67% (2/3)

+

1 = 33.33%(1/3)

=

(2+1)=3 or (66.67%+33.33%)=100% or (2/3+1/3)= 3/3

150.66 x 66.67%= 100.45 grams of Part A RESIN

150.66 x 33.33%= 50.21 grams of Part B CURING AGENT

100.45 + 50.21 = 150.66  A/B MIXTURE

GENERAL LAY-UP PROCEDURE

Apply the mixed resin onto the surface and then lay the fabric and allow the resin to saturate through the fabric.

NOT THE OTHER WAY AROUND

This is one of the most common processing error that yields sub-standard laminates. By laying the fiberglass onto a layer of the prepared resin, fewer air bubbles are entrapped during the wetting-out stage. Air is pushed up and outwards instead of forcing the resin through the fabric which will entrap air bubbles. This technique will displace air pockets unhindered and uniformly disperse the impregnating resin throughout the fiberglass.

HAND LAY-UP TECHNIQUE

Eliminating air entrapment or void porosity in an epoxy/fiberglass lay-up process

Fiberglass Hand Lay Up For Canoe and Kayak Building- Cedar Strip Kayak Fiberglassing - YouTube

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Basic Hand Lay-up Fiberglassing

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VACUUM BAGGING PROCESS

 For performance critical application used in aerospace vehicles, composite framing for automotive vehicles and marine vessels, a process called 'Vacuum Bagging' is employed to ensure the complete consolidation of every layer of fabric. The entire tooling and lay-up are encased in an airtight envelope or bagging and a high-efficiency vacuum pump is used to draw out the air within the vacuum bag to create a negative atmospheric pressure. Once a full vacuum (29.9 Inches of Mercury) is achieved, the negative pressure applies a compacting force of 14.4 pounds per square inch (maximum vacuum pressure at sea level) is applied to the vacuum bag transferring the force to the entire surface area of the laminate.
Vacuum pressure is maintained until the resin cures to a solid. For room temperature curing resin system, the vacuum pump is left in operation for a minimum of 18 hours. External heat can be applied to the entire lay-up, thus accelerating the cure of the resin system.
The vacuum force also removes any entrapped air bubble between the layers of fabric and eliminate what is called, porosity or air voids. Porosity within a laminate creates weak spots in the structure that can be the source of mechanical failure when force or load is applied to the laminate.  
The standard atmosphere (symbol: atm) is a unit of pressure defined as 101325 Pa (1.01325 bar), equivalent to 760 mm Mercury or 29.92 inches Mercury or14.696 pounds per square inch of pressure.

FiberglaSs And Carbon Fiber Vacuum Bagging and Flat Panel Laminate - YouTube

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AUTOCLAVE CURING PROCESS



 Autoclave curing processing is the most common method used in large-scale production of composite products. The Aerospace Industry, which includes space exploration rockets and vehicles, deep space structures, and commercial and military airplane utilizes this composite fabrication process due to the critical nature of the application. The mechanical demands of the composite are often pushed to the upper limits and autoclaved process yields composites with the best weight to strength ratio.

BASIC OPERATION OF THE AUTOCLAVE PROCESS
In the autoclave process, high pressure and heat are applied to the part through the autoclave atmosphere, with a vacuum bag used to apply additional pressure and protect the laminate from the autoclave gases. The cure cycle for a specific application is usually determined empirically and, as a result, several cure cycles may be developed for a single material system, to account for differences in laminate thickness or to optimize particular properties in the cured part.The typical autoclave cure cycle is a two-step process. First, vacuum and pressure are applied while the temperature is ramped up to an intermediate level and held there for a short period of time. The heat reduces the resin viscosity, allowing it to flow and making it easier for trapped air and volatiles to escape. The resin also begins wetting the fibers at this stage.In the second ramp up, the temperature is raised to the final cure temperature and held for a sufficient length of time to complete the cure reaction. During this step, the viscosity continues to drop, but preset temperature ramp rates and hold times then stabilize viscosity at a level that permits adequate consolidation and fiber wetting, while avoiding excessive flow and subsequent resin starvation. These control factors also slow the reaction rate, which prevents excessive heat generation from the exothermic polymerization process. Upon completion, the cured mechanical performance of the composite is often much stronger and lighter compared to a hand lay-up, or vacuum bagged composite laminate.

VACUUM INFUSION PROCESS

Vacuum Infusion Process is also known in the composites industry as 

Vacuum Assisted Resin Transfer Molding or VARTM.

Similar to the Vacuum Bagging Process where the negative pressure is used to apply consolidation force to the laminate while the resin cures, the resin is infused into the fabric lay-up by sucking the impregnating resin and thus forming the composite laminate.

The VARTM Process produces parts that require less secondary steps, such as trimming, polishing or grinding with excellent mechanical properties. However, the vacuum infusion requires more additional or supplemental related equipment and expendable materials. So the pros and cons of each presented composite fabrication process should be carefully determined to suit the user's capabilities and needs.

Please view the following video demonstration which explains the process of Vacuum Infusion or VARTM process.

MAX 1618 A/B VACUUM ASSISTED RESIN TRANSFER MOLDING PROCESS

CARBON FIBER VACUUM INFUSION WITH EPOXY RESIN - VACUUM BAGGING WITH MAX 1618 EPOXY RESIN - YouTube

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Step Four: Proper CuringAlthough we have formulated all of ur MAX EPOXY RESIN SYSTEM product line to be resistant to amine-blush,it is recommended not to mix any resin systems in high humidity conditions, greater than 60%.

Always make sure that the substrate or material the epoxy resin system is being applied to is well prepared as possible to ensure the best-cured performance. 

Always review the published data and information for proper usage, application, and general safety information.
Our expert staff of engineers is always available for consultation and assistance.

Allow the lay-up to cure for a minimum of 24 to 36  hours before handling. Optimum cured properties can take up to 7 days depending on the ambient cure condition. The ideal temperature cure condition of most room temperature epoxy resin is 22 to 27 degrees Celsius at 20% relative humidity.Higher ambient curing temperatures will promote faster polymerization and development of cured mechanical properties. Improving mechanical performance via post heat cure A short heat post cure will further improve the mechanical performance of most epoxy resins. Allow the applied resin system to cure at room temperature until for 18 to 24 hours and if possible, expose heat cure it in an oven or other sources of radiant heat (220°F to 250°F) for45 minute to an hour. You can also expose it to direct sunlight but place a dark colored cover, such as a tarp or cardboard to protect it from ultraviolet exposure. In general room temperature cured epoxy resin has a maximum operating temperature of 160°F or lower. A short heat post cure will ensure that the mixed epoxy system is fully cured, especially for room temperature cure system that can take up to 7 days to achieve 100% cureSome darkening or yellowing of the epoxy resin may occur if overexposed to high temperature (>250 F).
AMINE BLUSHThe affinity of an amine compound (curing agent) to moisture and carbon dioxide creates a carbonate compound and forms what is called amine blush. Amine blush is a wax-like layer that forms as most epoxies cure. If the epoxy system is cured in extreme humidity (>70%).It will be seen as a white and waxy layer that must be removed by physical sanding of the surface followed by an acetone wipe.

OTHER TYPES OF EPOXY RESIN CURE MECHANISMLATENT CURING SYSTEMSLatent epoxy resins are systems that are mixed together at room temperature and will begin polymerization but it will not achieve full cure unless it is exposed to a heat cure cycle. In general, these are high-performance systems that demonstrate exceptional performance under extreme conditions such as high mechanical performance under heat and cryogenic temperatures, chemical resistance or any environment that epoxy room temperature system perform marginally or poorly.  Upon the mixing of the resin and curing agent polymerization will begin and will only achieve a partial cure. Some resins may appear cured or dry to the touch,  this state is called 'B-Stage Cure', but upon application of force will either be gummy or brittle almost glass-like and will dissolve in most solvents. The semi-cured resin must be exposed to an elevated temperature for it to continue polymerization and achieve full cure. 
HEAT ACTIVATED CURING SYSTEMSThis type of epoxy system will not polymerize unless it is exposed to the activation temperature of the curing agent which can be as low as 200F and as high as 400F. In most instances, our MAX EPOXY SYSTEMS epoxy system can be stored at room temperature and remain liquid for up to six months and longer.
TESTING THE COMPOSITE
DETERMINATION OF THE FABRIC-RESIN RATIO 

TESTING FABRIC TO RESIN RATIO VIA RESIN BURN OUT - YouTube

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ULTIMATE COMPRESSIVE STRENGTH

 ULTIMATE COMPRESSIVE STRENGTH TEST OF FIBERGLASS LAMINATE TOOLING BOARD. - YouTube

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6500 pounds to failure / 0.498 square inch = 13,052 psi max compressive strength

SPECIMEN EXAMINATION AFTER COMPRESSION TEST - YouTube

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PLEASE CHECK OUT OTHER AVAILABLERESIN SYSTEMS AT OUR eBay STOREFor our complete listing, please Visit our eBay store!

DON'T FORGET OUR EPOXY MIXING KIT

Click The Link To Add To Order  https://www.ebay.com/itm/222623932456

EVERYTHING YOU NEED TO MEASURE, MIX, DISPENSE OR APPLY 

Proportioning the correct amount is equally as important to attain the intended cured properties of the resin system. The container in which the epoxy and curing agent is mixed is an important consideration when mixing an epoxy resin system. The container must withstand the tenacity of the chemical and must be free of contamination. Most epoxy curing agent has a degree of corrosivity, as a general practice, protective gloves should be worn when handling chemicals of the same nature.
MIXING KIT CONTENTS 

1 Each Digital Scale -Durable, Accurate Up To 2000.0 Grams   

4 Each 32-ounce (1 Quart) Clear HDPE Plastic Mix Cups

4 Each 16-ounce (1 Pint) Clear HDPE Plastic Mix Cups

One Size Fits All Powder-Free Latex Gloves 

2 Each Graduated Syringes

Wooden Stir Sticks

Assorted Size Foam Brush 

 

IMPORTANT NOTICE

Your purchase constitutes the acceptance of this disclaimer. Please review before purchasing this product.

The user should thoroughly test any proposed use of this product and independently conclude the satisfactory performance in the application. Likewise, if the manner in which this product is used requires government approval or clearance, the user must obtain said approval.

The information contained herein is based on data believed to be accurate at the time of publication. Data and parameters cited have been obtained through published information, PolymerProducts and  Polymer Composites Inc. laboratories using materials under controlled conditions. Data of this type should not be used for a specification for fabrication and design. It is the user's responsibility to determine this Composites fitness for use.

There is no warranty of merchantability for fitness of use, nor any other express implied warranty. The user's exclusive remedy and the manufacturer's liability are limited to refund of the purchase price or replacement of the product within the agreed warranty period. PolymerProducts and its direct representative will not be liable for incidental or consequential damages of any kind. Determination of the suitability of any kind of information or product for the use contemplated by the user, the manner of that use and whether there is any infringement of patents is the sole liability of the user.