MAS Epoxy Resins, imported from the USA, are preferred by many professional users for a number of reasons: No blush performance, unbelievable penetration, extremely good performance in cold conditions and ease of measurement due to the pre-calibrated pumps which are available.
MAS Epoxy resin comes in two types - FLAG (thicker) and LOW VIS (thinner)
These are then mixed with your preferred hardener - Slow, medium or fast.
1. What is the Mix Ratio?
The mix ratio of our Low Viscosity or FLAG Resin and MAS
Hardener is 2:1 Resin to Hardener. That ratio stays constant even when
the hardeners are custom blended. The Mix ratio for Rapid Cure 5 Minute
epoxy is 1:1.
2. Can I speed up the cure by adding more hardener?
NO!!! Changing the mix ratio will cause your final
product to be too flexible or not cure at all and then you’ll have to
scrape off the uncured epoxy.
3. How much mixing is required?
Mixing is the key to a thorough cure, good films, and
strong bonds. For Low Viscosity or FLAG Resin and MAS Hardeners 1½ to 2
minutes of aggressive mixing, swiping the sides and bottom is
recommended. Use clean plastic or uncoated paper cups or buckets and a
clean mix stick. Rapid cure should be mixed well for about 45 seconds.
4. What is BLUSH, and how do I remove it?
Blush may form over the Fast hardener and resin. The
Slow and Medium mix will not blush. Blush is noticeable as a slippery
film formed over the cured surface. It can be removed with warm water
and a sponge (rinse and wipe).
5. What is the recoat time?
Since epoxies from MAS are 100% solid (no solvent),
recoat time can be as short as surface tack. If more than 30 hours pass
between coats, we recommend a light scuff sand. Always check for blush
on surfaces and remove if present before recoat.
6. Temperature requirements?
For clear coating, we like to see temperatures remain over 65 to 70° F. For bonding, anything over 45°
7. How to clean up?
Latex 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 white vinegar or Isopropyl alcohol.
Semi-gelled epoxy (on tools ONLY) can be cleaned with acetone or
lacquer thinner.
8. 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.
9. How to protect the epoxy?
Epoxy surfaces should be protected from sun exposure.
Clear coats may be protected by a good quality varnish or urethane with
UVA protective additives. Paint is always considered a 100% filter.
Indoor pieces do not need varnish over the epoxy.
10. Can a stain be used on the project?
To use a stain on an epoxy project, use a waterborne
urethane stain under the epoxy clear coat. Oil based stains have been
used successfully. Be sure stain is fully dry before coating work with
epoxy. Always test first using the “Cross-hatch” test. Take a spare
piece of stained wood and coat it with epoxy ( make about an 8” box).
Once it has cured for a few days, take a utility knife and cut a
“tic-tac-toe” board in the epoxy. Take some Duct tape or strong packing
tape and place pieces onto the squares making sure they are firmly
attached. Pull the pieces of tape off. If the epoxy comes with it, it
won’t adher to the stain. If the wood comes off, or just the tape, it
has a good adhesion and you can use our epoxy over the stain. ( For
clear coating only)
11. What fillers can be used with the epoxy?
All dry fillers, regardless of the manufacturer. For more information see page 11 for fillers.
12. What protection is needed when using epoxy?
Disposable gloves should always be used and eye
protection is important if any splashing were to occur. If the
ventilation is poor a respiratory mask (like 3M Easy-Air) should be
used. Clean any uncured epoxy off of the skin with a waterless hand
cleaner immediately. The epoxy may cause irritation of the skin,
especially fair skin.
Avoid all direct skin contact with resin, hardeners and
mixed epoxy by wearing disposable gloves and other protective clothing.
NEVER use solvents to remove epoxy
from the skin. Always wash thoroughly with soap and water immediately
after contact. Protect your eyes by wearing protective eyewear. If
contact should occur, flush eyes immediately with running water for 15
minutes. If discomfort continues, seek medical attention. Avoid
breathing vapors. Use epoxy only in areas with good ventilation. In
small areas, be especially careful to have a supply of fresh air and to
exhaust any fumes. When ventilation is not possible, wear a respirator
with an organic vapor cartridge especially when sanding uncured epoxy.
Avoid ingestion. Wash thoroughly after each use and especially before
eating and smoking.
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 absorbent materials may be used to contain or soak up large spills. Clean residue with white vinegar or Isopropyl Alcohol. Dispose of resin, hardener and empty containers safely. Do not dispose of resin of 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 nonhazardous 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 mass has cooled. Then follow your local, state and federal regulations for proper disposal.
13. What is the shelf life of these products?
The resin has an infinite shelf life and the hardeners
have a shelf life of a minimum of 1 year in a closed container.
14. 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.
15. What are the major pitfalls that most users fall into?
Bad mixing practices are the cause of 99% of all
problems. The mix ratio Resin to Hardener is 2:1. The pumps are
pre-calibrated for ease of dispensing. One full stroke of the resin pump
and one full stroke of the hardener pump will give you the proper
amount. Once dispensed, mix, mix, mix and mix some more. Temperature:
Maintain close to 70°F or better if possible while curing. Epoxy loves
heat. Keep your resin and hardener warm (70°F) - even if you don’t heat
your shop. Don’t over clamp.
You don’t want to squeeze out the glue. Use the right
filler for the right job. Don’t use Micro Baloons to glue wood or fiber
glass. See our use schedule on page 4 for proper filler use. Patience -
Be patient. Epoxy takes time to cure. Let it do its job. Follow the cure
schedule on page 4.
16. How much coverage will one catalyzed gallon give?
Depending on your application technique, generally on
bare wood, you can cover 500 sq. feet 3 mil thick. See chart page 2.
17. How does temperature variation effect epoxy?
For every 18 degrees 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. See curing schedule on page 4.
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.
18. 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.
19. 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. open (working) time or wet lay-up
time(liquid); 2. Initial cure or gel; 3. Final cure is when the epoxy is
now solid. The speed and the length of these phases and total cure time
varies relative to temperature and which hardener was used - slow,
medium, or fast or combination of - and if additives have been
incorporated into the mixture. Cure times can be sped up or slowed
depending on your need and application by the combining of the different
speed hardeners. Cure times for the Fast hardener, combined with either
Low Viscosity or Flag Resin can be lengthened by the addition of 35-40%
of the Slow hardener. The Slow hardener can be sped up by the addition
of Fast or Medium 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 sped 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 maniuplate 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 and Fast and the following ratios are
the most popular for the listed common conditions:
Coating and Encapsulate: If
temperatures are slightly cool (50-60°), we recommend our Medium
Hardener 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 70°), this mix can be
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 to prevent
slumping and give you a longer work time.
20. Controlling Cure Time through mixed Quantity
Container Shape and Temperature A. Mixed Quantity - A
larger quality of mixed epoxy will create more heat and have a shorter
open (working) time and overall cure time. Smaller batches of epoxy
create less heat than larger batches and also have longer workng and
cure times. In other words, a thicker layer of epoxy will cure sooner
than a thin layer. B. Container Shape - The mixture's heat can be
distributed by pouring the mixture into a larger, flatter container
(like a roller pan, for example.) This also extends the open time. C.
Temperature - Heat can be applied or removed from the epoxy to shorten
or extend open and cure times. After the epoxy is applied, a fan can be
used to draw heat from the lay-up or application and extend the epoxy's
open time. Moderate heat (an industrial hot air gun, hair dryer or heat
lamp) applied to the layup or to the resin and hardener before mixing,
will shorten the epoxy's pot life and cure time.
21. Gel coat over epoxy
If you are making a repair on a gel coat of a boat, you
need to sand down the gel coat and feather out the edges of the area to
be repaired so that you will get a permanent secondary bond. An 8:1
feathering ratio will work fine. Make the repair out of epoxy ( see #23)
and then let it fully cure. Coat the cured epoxy with a thin coat of
(BPO) cream hardener style polyester fairing compound. Make it fair
(smooth) Then use the Gelcoat to cover. The Fairing compound acts as a
tie coat for the adhesion of the gelcoat to the epoxy repair.
22. Coloring Epoxy
MAS Epoxy can be colored by using an epoxy pigment,
usually available in your local Marine Chandlery. MAS Epoxy can also be
colored using Acryllic Artist Paints you buy at an Art Supply Store.
These come in a tube and are a high viscosity (similar to tooth paste).
Mix the resin and hardener thoroughly first, then add the colorant. Just
like when using stains, we recommend you test, first, on a noncritical
part or spare piece to check for adhesion and color opaqueness.
23. Bonding/ Coating Aluminum
You need to pre clean and treat the Aluminum to be
bonded with Dupont 225-S Cleaner. Once that is done you need to convert
it using 226-S. These Dopont products can be purchased through a Marine
or Autobody Supply store.
24. Blister Repair
Polyester Resin is used in the production of most boats
now afloat and it’s not waterproof. Polyester Resin has a very high
osmotic absorption rate (how much water the solid absorbs). Usually,
water penetrates the gel coat below the water line; however we’ve seen
instances where blisters appear above the water line as well. Blisters
are caused when the water passes through the outer skin of the laminate,
i.e. gelcoat.
When migrating water finds an osmotic home and begins to
collect, pop, you have a blister. A blister is an area within the glass
that expands to hold more water and causes the laminate to swell.
Blisters may show as a bulge on the surface. To begin, you’ll need to
remove all paint on the surface and have a clear view of where the
blisters are. Once you’ve located the bubbles or blister on the surface,
on the larger blisters, you’ll need to drill a hole in the lower
portion of the blister to allow the trapped water, etc. to escape. After
this is completed, you’ll need to grind away the complete blister -
like an upside down volcano into the laminate. You’ll know when all the
damage material is ground away when you hit hard, clean material again.
We should mention the water behind the outer skin will smell and the
material will be spongy in texture and discolored.
FILLING THE VOID Feather out the edges
of the divot you’ve created. A feathering ratio of at least 8:1 will
allow permanent secondary bonding of the repaired area. When you’ve
completed the removal of all blisters, allow the boat to dry by storing
indoors or tenting the hull from the weather. You may also consider
applying heat to help dry out the composite before you begin to repair.
Get hold of a moisture meter and check the moisture content of the hull.
If you can’t get hold of a moisture meter, please call us for
recommended dry schedules.
Now you can begin rebuilding the surface. Our
recommendation for filling back divots is making your own filler by
blending Phenolic Micro Balloons (Purple in color) and Cab-O-Sil 75/25
respectively. (See Fairing recipe on page 14 ) Now, fill back the holes
using a putty knife or large squeegee. If substantial structural glass
has been removed in the grinding process, new glass can be applied prior
to applying filled epoxy or Fairing Compound. Let the epoxy filler mix
harden for 12 - 24 hours at 77° before attempting to sand or work the
surface.
You may recoat with either a filler epoxy blend, or
clear coat with straight resin/hardener mix. After the surface is smooth
or “fair”, you may begin putting multiple coats of mixed epoxy on the
bottom as you build a barrier coat. (5 coats are recommended to build at
least 20-40 ml of thickness). This insures no further water penetration
and a thickness you won’t sand through when prepping for bottom paint.