Resins

[Tx49]

I have some talent in the area of carpentry, design, and rudimentary engineering principles. I know the basics of laying fiberglas. What I don't know is anything about the actual resins and glass.  I know that my boat was built with polyester resin, so shouldn't poleyester be good enough for everything I have planned. If so I have found these three types.


Do I need all three?. Just 2? Would the boatyard work for everything. I'm lost. I don't trust the people selling stuff. I trust the people using it.  keep in mind, I'm not necessarily buying from WEST, I will be pricing it out, but I'm just trying to get the types of resin figured out and what kind of quantities I'll need for the initial transom, stringer and hull extension. I guess I should also check on the hull truth for San Antonio area boaters who can point me to some area boatwrights. Not a knock against this community, but it is a smaller community with a more southeast base. haven't seen any from my area anyway.

[seabob4]

When it comes to glass, they build them the same way, whether it's Washington state, Miami, SoCal, or Maine.  Even San Antonio...

[slvrlng]

For making laminates stick to old glass epoxy cannot be beat. yes, it is more expensive but you have a much longer work time than any poly product. take Rickk's lead, he is building any structure ( like his stringers and bulkheads) out of poly, but then gluing and tabbing them to the old glass with epoxy. I have been using both marine epoxy 2 to1 and us composites 3 to 1. The US stuff sets up much harder than the marine epoxy. Epoxy has a secondary bond that poly does not. They are very competitive on price and shipping epoxy since it is not flammable is much cheaper than poly.

 http://www.uscomposites.com/epoxy.html

http://boatbuildercentral.com/proddetai ... bi4Hvl1_Sg

[orb]

As far as resins go, this is what I have found. All these boats were built with polyester, and built or layed in a single layup, it that has good strength. Polyester is not so good for secondary bonding, meaning, laying polyester on top of polyester after it has cured. Even if prepared well it's mechanical adhesive properties are rather low. That being said, tons of people still use polyester for fiberglass repairs. Also polyester is not 100% water resistant- it absorbs water at a very slow rate/ but does absorb nonetheless.

The next best thing is vinylester. It has more than twice the mechanical adhesive properties than poly, and is completely water resistant. It costs about 180$ per 5 gallon bucket, almost twice that of poly. This is what I am using on the majority of my rebuild. To me Vinylester is a great inbetween product- not quite as expensive as epoxy(vinylester is easier to work with in my opinion) but much more superior to poly.

Next is epoxy. Epoxy has about 5 times the mechanical adhesive properties than polyester. Epoxy is great for high strength repairs -like tabing or glueing down stringers. From West Epoxy systems is about 140$ for a gallon of resin and a quart of hardener.

I buy all of my materials from composites one, a fiberglass distributor. I just set up an account using my business name- although I am not in the boat building business- and call ahead and pick it up at their warehouse. There may be a similiar distributor in your area. I have saved a good deal of money on buying coosa board from them.

[CLM65]

I fully agree with Lewis and orb.  I struggled with what to use on my rebuild, and was leaning towards vinylester, but Eugene at Shipoke (who does alot of rebuilds) convinced my that poly is more than adequate for what I'm doing, as long as the surface is prepared properly.  From the limited fiberglassing I've done so far, it seems pretty strong.  That being said, my rebuild is much more straight forward than yours.  If I was cutting my hull in two and adding a new section, I think I wouild opt for the added bonding strength of vinylester at a minimum, and probably epoxy for added confidence.  Just keep in mind that if you go with epoxy, you will not be able to use poly or vinyl resin, or gelcoat for that matter, to attach to the epoxy, as they will not stick well to cured epoxy (although epoxy sticks well to cured poly resin).

[Tx49]

I originally was thinking that I would use epoxy for a lot of this but then I saw a price of $400 for 4.35 gallons. I thought of vinellester also. Would it work to use vinylester to build up the extension and then add a bonding tab like a scab over the extension joint with epoxy. Then use vinylester for everything under the floor- tabbing and coating, and use poly above the floor. I am also worried that if I use epoxy much, I will end up with some area that won't bond right because I mixed up where to use what. I know people swear by epoxy, but there are a lot of successful projects that only see poly and/or vinylester.

[Tx49]

When it comes to glass, they build them the same way, whether it's Washington state, Miami, SoCal, or Maine.  Even San Antonio...

Oh I know. I just meant so i could have some local shops to go to for help in person like you guys have all over florida new jersey and carolina.  

[RickK]

I originally was thinking that I would use epoxy for a lot of this but then I saw a price of $400 for 4.35 gallons. I thought of vinellester also. Would it work to use vinylester to build up the extension and then add a bonding tab like a scab over the extension joint with epoxy. Then use vinylester for everything under the floor- tabbing and coating, and use poly above the floor. I am also worried that if I use epoxy much, I will end up with some area that won't bond right because I mixed up where to use what. I know people swear by epoxy, but there are a lot of successful projects that only see poly and/or vinylester.

You should put your location in your profile (it'll show up under your username) so we know where you're from and people can direct you to local deals.  
I can buy 7 gals of epoxy at $320 and that is retail price through US Composites.  They have a website that you order from and they ship UPS.
My $.02 is use epoxy below the floor and poly above.  That's what I'm doing on the my 170 rebuild.  Orb mentioned bonding strength - I googled that and saw that poly is 100 and epoxy is 2000.  
So that is why I went with epoxy below the floor.  Above the floor will be all gelcoat so I'll go back to poly at $85/5gal.

[slvrlng]

If you look at the us composites prices you will see that its 320 bucks for 7.5 gals for the 2 to1. Plus shipping. Check out the Southport site and they tell you why they use vinylester. The vinylester starts getting into the same prices as epoxy and shipping is higher because of hazmat.

http://www.southportboats.com/construction/

Have you read anything over on www.bateau2.com? Lots of info there as well.

[Tx49]

thanks Rick and slvring. I will check out those sources. I am going to be using a lot of resin as I am going to be adding an extension, replacing all the stringers, adding bulkheads, etc. That's why I was worried about the cost of epoxy. My time limitations will cause this to be slow enough, I don't want to have to save up forever to afford the resin.

[orb]

Would it work to use vinylester to build up the extension and then add a bonding tab like a scab over the extension joint with epoxy. Then use vinylester for everything under the floor- tabbing and coating, and use poly above the floor. I am also worried that if I use epoxy much, I will end up with some area that won't bond right because I mixed up where to use what.

I was of the same thought, or rather had the same questions and ideas. I had planned on building the extension in the mold, which was attached to the hull, and barely tab it up on the hull, then tab it further with epoxy. But then I did some research on vinylester, and read
http://www.thehulltruth.com/boating-for ... in-ob.html
on the hull truth. I messaged the guy rebuilding the boat , Bly, and he said he only used vinylester throughout on his extensive rebuild. I then decided I would run the vinylester resin and cloth up onto the existing hull about 16 inches. Then build the stringers -match old ones - out of coosa and glass then pretty thick, then tie them down with epoxy. The new stringers cross the joint up onto the old hull by about 24 inches.

[fishinonthebrain]

For my CCP 222 rebuild I used epoxy for stringer repair and transom replacement. Then vinylester for floor and topside repairs or any fabricated parts so I can use gelcoat. I second the US composites for all supplies epoxy, vinylester, fiberglass cloth, and gel coat.

[Tx49]

For my CCP 222 rebuild I used epoxy for stringer repair and transom replacement. Then vinylester for floor and topside repairs or any fabricated parts so I can use gelcoat. I second the US composites for all supplies epoxy, vinylester, fiberglass cloth, and gel coat.

It is way down the road, but this does bring up the subject of Gelcoat. I had not really thought of doing gelcoat. I was just planning on paint. Should i want gel coat? Any theory on where it is best used from a budget standpoint. Bottom only, Exterior, Everywhere. I am not a body man or a boatwright, but everything on this boat will be done by me with a little help from sons and friends. Is gelcoat something I could tackle or should i just use good  marine paint.
epoxy or such.

[gran398]

Always great discussion regarding gel and paint..The good, the bad, and the ugly.

Let's put that aside for just a short while.

We're glad that you've joined  As you can see...we're a small group here. Please tell us your first name, so that we can call you by name going forward, as part of our group..and also tell us a bit about yourself.

Thanks

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[Tx49]

Well the only reason I am replied about it now is because, if i am going to use gelcoat, I think that I would need to put it in my extension mold  before I lay up the extension and on my transom layup. No? Yes?