Epoxy Brands, Types, and Applications

76SeaRay

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I read the sticky on Fiberglass resins and that was very helpful but I am wondering about the various types and their applications. I have 4 different needs and wondering if one epoxy will do all or should I use different epoxy types for each type of job. Looking for recommendations for the following:

1) Laminate layers of 3/4 inch marine plywood for a new transom
2) Bond the new transom to the hull
3) Tab and cover the new transom and new stringers
4) Floor covering

I see the two following links with a large number of brands and types:

http://www.iboats.com/Boat_Epoxy_Res...view_id.217327


http://www.fiberglasssupply.com/Product_Catalog/Epoxy/epoxy.html

I am working indoors with a shop that I can maintain about 50 to 55 degrees during these winter months. I am in southwest Washington so a damper climate this part of the year.

Thanks...
 

alldodge

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Epoxy will do all that poly resin will do and also bonds better to things then poly resin. Epoxy will do all of what your wanting to do. Issues is it takes longer to fully set, and if it goes much past when it has fully set up it can what is called blushing.

When the resin blushes, it get a dull white film on top. Once it blushes, the blush will need to be removed to add another layer. That said if you time your coats, there will be no need to remove blush because a new layer can be applied before epoxy fully sets up.

Check out US Composites for more info
 

Mad Props

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Most popular epoxy resins are going to work very well (west systems, total boat, us composites, etc). Stay away from cheap resins as you'll get what you pay for.

That said, I didn't use epoxy in my build, but kinda wishing I did as I'm at a standstill on fiberglass work with these temps.
 

kcassells

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US Comp has a very good description of the types and uses of eeeeepppoooxxxiiieees.T
hey have slow, med and fast. Being your temps are currently as said a medium is fine. Gives a nice time to actually saturate into the wood. If you want speed in those temps a hot mix would cure slowly also.
Hit the site and read. I started with them and have not had to look anywhere else.
Iboats has good products too.
 

dezmond

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I have used West System throughout
my build so far with great results. Transom, tabbing, fillets, etc. Pick the different hardner for the job. When I want to soak the resin in my plywood, I use the slow hardener. If I am tabbing my stringers I use the fast. Blush isn’t really an issue. If you do get it, it’s best to use soapy warm water and a scotch brite pad. Then dry it off and your good to go. No need to wipe with acetone or grind or sand (unless you need to fix something). These words came directly from West Systems. Yes it takes longer to cure than poly but I’m in no hurry ;)
 

76SeaRay

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Thanks. I am in no hurry either so using a slower hardener would work for me. So another question is that my transom is 86 inches wide, 36 inches tall in the middle and 24 inches tall at each side. I am estimating the surface at 20 sq ft. How big a batch of epoxy would be needed to cover/soak the plywood layers? Also, how big a batch of PB would be needed to cover the same space to bond the plywood to the hull? Is there a rule such as a quart will cover X sq ft, etc. that can be used to scale the batch and use it within the set time?
 

alldodge

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Epoxy doesn't need glass cloth to bond, that said it still needs enough to soak into the cloth. Look at the us composite site and it provides estimates of how much will be needed. Every layer used, if more or less length on the tabbing, how much cabosil or other as a thickener. You want leftovers, not good to come up short
 

Scott Danforth

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anticipate buying 1.5 to 2x what you think you will need and you may need more

as AD stated, always good to have extra, you do not want to be in the middle of a task and come up a quart short.
 

zool

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Epoxy doesnt have shelf life issues like poly, so theres no harm in having extra....also, less is more with epoxy, so you can easily guage when your getting "low" and need to order more....
 

76SeaRay

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Thanks, probably wasn't clear on my question. I don't mind over buying at this point since I have a lot to do but was wondering about the mixed batch instead, that is, how much to mix up at a time for the surfaces I mentioned above... Don't want to over mix and waste it or run short when bonding the layers together or bonding the new ply to the hull.. Will look at the US Composites site again...
 

harringtondav

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I've had only one experience with this topic and used West System products with good results for a newbie. Available here at iBoats. I was working with it during a hot weather spell, so I learned the hard way about pot life. Ordering extra is good advice, especially if you're in a learning curve like I was.
 

JonNmtJuliet

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i just completed what you are about to do on a transom very close to your size. I coated each side twice before installing using us composites 3:1 epoxy. I believe on the first coat I used 6 oz of epoxy and 2 oz of hardener. I least I think its oz's its the mixing cups they sell. Then the second coat I did 3 oz and 1 oz on the second coat. You can always start with this and keep making batches to finish what you are doing with little waist. I really doesn't take a long time to make each batch. I used pl to glue the transom together so no help there but did use epoxy pb to glue the transom in. I used close to a 9oz epoxy and 3 oz hardener mix to glue it in. I just kept mixing cabosil (I bought the large bucket used a 1/4 so far) in until I got a mayonnaise mixture.

caveat emptor -- I'm learning as I go but just thought I'd share what I've found so far. Just take your time use gloves always and when mixing the cabosil use a mask and stay away from a wind it will blow everywhere. You have plenty of time with the 3:1 before it sets. I'm sure you will do fine.
 

zool

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If you want to control waste, Have pieces of wood or areas of the boat ready that need to be coated, and use whats left in the pails to coat them. You can also have a good amount of cloth pieces pre-cut for tabbing, and do the small areas with the residual resin.
 

JASinIL2006

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If you want to control waste, Have pieces of wood or areas of the boat ready that need to be coated, and use whats left in the pails to coat them. You can also have a good amount of cloth pieces pre-cut for tabbing, and do the small areas with the residual resin.

This is good advice...
 

76SeaRay

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I picked up a gallon of West Systems 105 and a quart of their 206 slow hardener to start. I looked at their products for filler to make peanut butter but they have multiple different types; 403 microfibers, 404 high density, 405 filleting blend, 406 colloidal silica, 407 low density and 410 microlight. Their selection guide was not all that helpful in determining which one to use for the transom plywood to hull. Suggestion on which one to use? Is there another product that might be cheaper but work with the 105 system?

Thanks.
 

harringtondav

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For tabbing and filleting I don't think an expensive filler is necessary. It adds thickness to avoid slump. It also adds strength to stressed joints.

I used West's pricey 404 white high density filler for a small job. It has outstanding adhesion and strength properties, but was overkill for my application. It was my first experience, so I went Cadillac for comfort.
 

Woodonglass

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Since you're using epoxy you can use just about anything. Wood dust from your sander, Baby Powder etc. No need for the expensive stuff.
 

zool

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I picked up a gallon of West Systems 105 and a quart of their 206 slow hardener to start. I looked at their products for filler to make peanut butter but they have multiple different types; 403 microfibers, 404 high density, 405 filleting blend, 406 colloidal silica, 407 low density and 410 microlight. Their selection guide was not all that helpful in determining which one to use for the transom plywood to hull. Suggestion on which one to use? Is there another product that might be cheaper but work with the 105 system?

Thanks.

For ur transom, 406 is best imo because of its adhesion and gap filling properties,works well for ur pb mix for filleting also.

For glass boat repair/restoration, you can do the whole project with 406 and 407/410 for fairing.

I keep most of them on hand and blend them sometimes for certain applications, like adding some 403 or 406 to the 410 mix to help keep the fairing mix from sliding down vertical areas.

You can also save by using USC's buckets of cabosil, micro bubbles and balloons, ect in place of the the WEST products
 

76SeaRay

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I plan to do one coat of straight epoxy to the transom plywood and edges, let that cure, then light sand it before putting it in. I assume then the best thing to do is apply the peanut butter to the hull and mate up the transom plywood and that I don't need to wet the plywood again before mounting to the hull. What thickness is best for troweling on the peanut butter and do you use a notched trowel with let's say 1/4 inch V groove?
 

JASinIL2006

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You can apply to just one surface, but if you have time before the PB sets up, back-buttering the transom plywood will give you much better adhesion.
 
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