Tech Support FAQ
IMPORTANT FAQ's:
1. What are the differences between Epoxies, Vinylesters and Polyesters?
2. Glassing with Knitted Reinforcements?
3. Tips and techniques for filler use and selection (filleting and fairing)?
4. All about blister repair and barrier coating
5. MAS Epoxies Cure Schedules
6. Tg Graph of typical laminate cure using MAS Medium Hardener?
7. What is the Mix Ratio?
8. Can I speed up the cure time by adding more Hardener?
9. How much mixing is required?
10. What is BLUSH, and how do I remove it?
11. What is the recoat time?
12. Temperature requirements?
13. How to clean up?
14. What tools are used to apply the epoxy?
15. How to protect the epoxy?
16. Can a stain be used on the project?
17. What protection is needed when using epoxy?
18. What is the shelf life of these products?
19. What surface preparation is needed prior to application of epoxy?
20. What are the major pitfalls that most users fall into?
21. How much coverage will one catalyzed gallon give?
22. How does temperature variation effect epoxy?
23. Checking for Hardness - Using the Rule of "Thumb"
24. Customizing Cure Times - the blending of Slow and Fast Hardeners
25. Important Information about Ethanol fuel in your engines
1. What are the differences between Epoxies, Vinylesters and Polyesters?
Epoxies, Vinylesters and Polyesters represent two resin familes. Epoxies can be cured with amine agents at room temperature to form excellent adhesive and composite resins. Vinylesters and Polyesters contain an unsaturated ployester or hybridized vinylester backbone which is catalyzed with a peroxide to condense into cross-linked solid resin. Read more about Epoxies, Vinylesters and Polyesters...
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2. Glassing with Knitted Reinforcements?
Knitted reinforcements (as opposed to woven rovings and cloth) come in a variety of weights (usually described in ounces per square yard), fiber orientations, and with various backings stitched onto the reinforcing fibers with bias yarn. Read more about Glassing with Knitted Reinforcements...
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3. Tips and techniques for filler use and selection (filleting and fairing)?
No longer is it necessary to have many different resin systems around for laminating, filling, filleting, fairing and adhesive bonding. One simple MAS Resin and two hardeners, MAS Slow and MAS Fast, will provide you all the flexibility required to make different thickened putties for standard build and repair operations. Read more about filleting and fairing...
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4. All about blister repair and barrier coating
To understand the repair of blisters, you should learn what causes them, and before you apply a barrier coat on a new surface, leearn more about how to prepare the surface. Read more about blister repair and barrier coating...
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| Resin/Slow | Resin/Medium | Resin/Fast | |
| Temp. | |||
| 140 | 1.5m/28m/11:15h | 1.22m/16m/7:52h | 39s/11.5m/4.5h |
| 131 | 2.25m/42m/16:52h | 1.83m/24m/11:34h | 58s/17.25m/6:45h |
| 122 | 3.0m/56m/22.5h | 2.44m/32m/15:45h | 1.3m/23.0m/9.0h |
| 113 | 5.75m/1:15h/30h | 3:32m/45.0m/21.0h | 1.75m/30.0m/12.oh |
| 104 | 8.6m/1:52h/45h | 4.88m/67m/31:30h | 2.63m/45m/18h |
| 95 | 11.5m/2:30h/2.5d | 6.5m/1:30h/42.0m | 3.5m/1.0h/1.0d |
| 86 | 17.25m/3:45h/3.75d | 9.75m/2:25h/63.0h | 5.3m/1:30h/1.5d |
| 77 | 23.0m/5.0h/5.0d | 13.0m/3.0h/3.5d | 7.0m/2.0h/2.0d |
| 68 | 34.5m/7.5h/7.5d | 19.5m/4.5h/5.25d | 10.5m/3.0h/3.0d |
| 59 | 46.0m/10.0h/10.0d | 26.0m/6.0h/7.0d | 14.0m/4.0h/4.0d |
| 50 | 69.0m/15.0h/15.0d* | 39.0m/9.0h/10.5d | 21.0m/6.0h/6.0d |
| 41 | 92.0m/20.0h/20.0d* | 52.0m/12.0h/14.0d | 28.0m/8.0h/8.0d |
| * Not recommended | |||
6. Tg Graph of typical laminate cure using MAS Medium Hardener?
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The mix ratio is 2:1 Resin to Hardener. That ratio stays the same when the hardeners are custom blended (See item 19). When blending hardeners, blend In separate containers from the resin then mix with the Resin. Be sure to maintain the 2:1 ratio, resin: hardener.
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8. Can I speed up the mix my adding more Hardener - ABSOLUTELY NOT! Adding more hardener throws off the ratio and you will end up with a gooey mess that never cures.
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9. How much mixing is required?
Mixing is the key to a thorough cure, good films and strong bonds. One and a half to two minutes of aggressive mixing, swiping the sides and bottom is recommended. Be sure mix ratio is two parts resin to one part hardener. (2: 1). Use clean plastic or uncoated paper cups or buckets and a clean mix stick.
We also recommend taking the mixed batch and putting itinto a clean container, scraping the sides and bottom and then mix again. this assures a complete mix.
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10. What is BLUSH, and how do I remove it?
Blush is noticeable as a slippery film formed over the cured surfaces. It can be removed with warm water and a sponge (rinse and wipe). All the current MAS Hardeners are Non-Blushing. We developed the Fast Non-Blushing in 2005, and there may still be some of the older FAst around. Be sure the label says Non-bushing.
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Since epoxies from MAS are 100% solid (no solvents), recoat time can be as short as it takes to achieve surface tack. If more than 12 hours passes between coats, do a light scuff sand. Use a cotton ball to test if a light scuff sand is needed. If the epoxy holds the hair of the cotton ball, you can recoat without sanding. If it doesn't, a light scuff sand will help adhesion between coats. Remember the "Rule of Thumb" test (if you can press your thumbprint in the epoxy, but there's no tack, then you should do a scuff sand, but will be getting a chemical as well as a mechanical bond.) Remember, warmer conditions makes for a faster set.
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For clear coating, we like to see the resin remain over 55 to 60 F. For bonding, anything over 45 F is adequate.
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Gloves and other personal protection should always be used. If you should get any epoxy on your skin, it should be cleaned off with a waterless soap immediately, then thoroughly washed with soap and water. Tools can be washed with Bio Solv, white vinegar or isopropyl alcohol. Semi-gelled epoxy can be removed with acetone.
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14. What tools are used to apply the epoxy?
For coating and fiberglass, a short nap 1/8" nylon bristle roller, plastic squeegee, or disposable brushes. For bonding, a glue brush or a squeegee with notches cut into the edge.
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Epoxy surfaces should be protected from sun exposure. Clear coats may be protected by a good quality varnish or urethane with UVA protection additives. Paint is always considered a 100% filter. Indoor pieces do not need varnish over epoxy.
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16. Can a stain be used on the project?
To use a stain on an epoxy project, use a waterbased stain under the epoxy clear coat. Be sure stain is fully dry before coating work with epoxy. Always test first using the cross hatch test: Apply the stain n a scrap piece of wood. Let it dry. Apply the epoxy over the stain and let it sit overnight. Next day cut a tic-tac-toe image into the epoxy with a shop knife. Place a piece of Duct tape on each of the nine squares. Try to remove the epoxy. If it come off easily without any wood chards then there is an adhesion problem and will not work, but if it comes off with bits of wood attacheded the epoxy is penetrating the stain and will adhere well.
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17. What protection is needed when using epoxy?
Disposable gloves should always be used and eye protection is important if any splashing were to occur. A respiratory mask (like 3-M Easy Air) should be used. The epoxy may cause irritation of the skin, especially, fair skin.
A. Avoid all direct skin contact with resin, hardeners and mixed epoxy by wearing gloves and other clothing. Clean any uncured epoxy off the skin with waterless soap immediately after contact. NEVER use solvents to remove epoxy from the skin. Always wash thoroughly with soap and water immediately after contact.
B. Protect your eyes by wearing protective eye wear. If contact should occur, flush eyes immediately with running water for 15 minutes. If discomfort continues, seek medical attention.
C. Avoid breathing vapors. Use epoxy only in areas with good ventilation. In small areas, be careful have a supply of fresh air and to exhaust any fumes. Wear a respirator with an organic vapor cartridge. Wear a dust mask when you sand the epoxy. If it has cured for less than a week, use a respirator with the organic vapor in combination with a dust pre-filter.
D. Avoid ingestion. Wash thoroughly after each use and especially before eating or drinking.
E. Clean up spills with a squeegee and paper towels. Scrape up as much material as possible with the squeegee before using the paper towels. Sand, clay or other materials may be used to contain or soak up a spill. Clean residue with white vinegar or isopropyl alcohol. Always wear protective gloves when cleaning up spills or at the end of a job.
F. Dispose of resin, hardener and empty containers safely. Do not dispose of resin or hardener in a liquid state. Before disposing of resin and hardener containers, puncture the corners of can and drain residue into clean containers for re-use. Small quantities of resin and hardener can be mixed and cured completely to a non-hazardous solid. Place pots of curing resin and hardeners outside on the ground to avoid the danger of excessive heat and vapors. Dispose of after the reaction is complete and the mass has cooled. Then follow your local state and federal regulations for proper disposal.
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18. What is the shelf life of these products?
Shelf life is one year in a sealed container.
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19. What surface preparation is needed prior to application of epoxy?
All surfaces should be cleaned of any contaminates, such as oil, grease and pooled water. Light sanding is recommended. A clean cloth moistened with isopropyl alcohol or plain water may be used to clean surfaces and to remove dust. DO NOT USE ACETONE or a TACK CLOTH to clean the surface.
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20. What are the major pitfalls that most users fall into?
Bad mixing practices cause 99% of all problems. MIX, MIX, MIX and MIX some more. During coating, the temperature falls below dewpoint. A little temperature goes a long way toward good coating. Weak bond is a result of too much clamp pressure, The key to a strong bond is light pressure and adding the correct filler. Allow maximum clamp time and warming the piece can reduce this time (a light works well).
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21. How much coverage will one catalyzed gallon give?
Depending on Your application technique, generally, you can cover 500 square feet, 3 mil thick.
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22. How does temperature variation effect epoxy?
For every 18 F, the temperature falls below 77 F, the pot life will double for the mix. The thin film set will come close to a 1.3 increase in time. The exact opposite will occur as temperatures increase above 77 F. Applications which are allowed to cool below the freezing point must be warmed to achieve a full through Cure. In the case of freezing the solid or film must be checked for hardness to insure full, strength has been achieved.
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23. Checking for Hardness - Using the Rule of "Thumb"
To quickly check for full hardness, press thumb nail into solid or coating firmly (no indentation should occur). This test is also very helpful when determining if a piece is ready for sanding or machining.
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24. Customizing Cure Times - the blending of Slow and Fast Hardeners
The time it takes for an epoxy mixture to change from liquid to solid is the Cure time. There are three phases - 1. pot ife - time it will take the product in the container to gel 2) Thin Film Set - which is open (working) time or wet lay-up time. (liquid) ; Time to the Initial cure or gel 3. Full cure is when the epoxy is totally solid and reached its maxiumum strength
The speed and the length of these phases a cure time varies relative to temperature and hardener was used - slow, medium, or combination of - and if additives have been incorporated into the mixture.
Cure times can be sped tip or slowed depending on your need and application by the combining of the different speed hardeners. Cure times for the Fast hardener, combined with the low viscosity Epoxy resin can be lengthened by the addition of 35-40% by volume of the Slow hardener. This happens because the Slow generally has a peak exotherm temperature and the Slow hardener molecules are bulkier, which slows down the chemical reaction between the resin and hardener. The Slow hardener can be sped up by the addition of Fast hardener, however, it is important to note, the amount of Fast exceeds 30% by volume, compromise the "no-blush" characteristics of Slow Hardener. Remember -- the mix ratio between the resin and hardener still continues to be 2:1 resin:hardener.
NOTE -- The cure times are not directly proportional to the amount of hardener used to customize the blend. For example, if 25% Fast is added to Slow, the cure time is speeded by 12-15%. Conversely, if 50% of Slow is added to Fast, the cure time is slowed down by 25%.
The above ratios should get you in the curing ball park of a perfect shop/labs which warms and cools by increments of 18 F (see above). However, using both temperature variation and blending ratios which favor the "hot" side to manipulate a pot life, will probably get you close to your desired cure speed. Even if the pot life and thin film set of your first hybrid mix does not fall right on the money, the mix will cure as long as the resin to catalyst ratio is 2:1 and temperatures are not severely cold. We have been working with Hybrid blends of Slow Fast and the following ratios are the most popular for the listed common conditions: Coating and Encapsulate: If temperatures are slightly cool (50o-60o), we recommend our Medium Harderner. This can provide a blush free coating (but do check), and is normally sandable in the morning (remember, always mix resin and catalyst in a 2:1 ratio, mix thoroughly).
Filleting and Bonding: Normally since users are looking for maximum strength and minimum clamp time, we recommend 100% Fast. However, if the weather gets hot (over 80 F), this mix can he controlled by adding approximately 25% Slow, or switching to Medium hardener (Remember always mix Resin and Catalyst in a 2:1 ratio, mix thoroughly). For large fillets Medium hardener is recommended.
| Activity | Recommended Product |
| Bonding Porous Woods | Any of our Resin and Hardener mixes may be used with Cab-O-Sil or Wood Flour to thicken. |
| Bonding Dense Woods | Pre-coat pieces to be bonded with MAS Resin/Slow Mix, bond with Cab-O-Sil filled mixture. |
| Bonding Iron and Steel | Pre-coat with MAS Resin/Slow mixture. Rub mix into clean surface with scotch brite pad. |
| Bonding Aluminum | Pre-clean and treat with DuPont 225-S cleaner. Convert with 226-S (Bond like dense wood). |
| Bonding Foam and Core | Same as dense wood. |
| Laminating Wood Structures | All products, depending on the size of the structure for dense wood. MAS Resin/Fast mixture or Medium mixtures are good for deck deck beams, stringers, etc. |
| Filleting (structural) | MAS Resin/Medium Speed Hardener thickened with Cab-O-Sil (1 part) and then filled with Wood Flour until looking just dry. |
| Filleting/Fairing (cosmetic) | Same as structural, but substitute low density filler (i.e., Microballons for the Wood Flour). |
| Laminating Fiberglass | MAS Resin mixed with Fast or Slow Hardeners. Use Slow for "No Blush" and green stage next day - the surface will be ready for more work while requiring no prep. If using Fast or Medium, watch for Amine blush and remove it before continuing. |
| Osmotic Barrier | MAS Resin and Slow Hardener. 5-9 coats (optimal temperature while curing is 70 degrees F.) |
| Vacuum Bagging | MAS Resin and Slow Hardener |
25. Important Information about Ethanol fuel in your engines
Got Ethanol? Quick Facts
Ethanol - What you need to know
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