Epoxy on Polyestrer Hull

[blastoff]

Well it's looking like my ACCELLERATOR Catamaran hull is made of fiberglass and resin The parts I glued are not really grabbing or bonding ???
Has any one had a bad experience with using epoxy on a polyester hulls ???

[Bill-SOCAL]

I try to avoid epoxy on polyester resin hulls. You can try cleaning it with acetone or mineral spirits and scuffing it up to help, but the two are fundamentally incompatible.

I like to use GOOP. Sticks like mad yet will release when you want it to. I also use the stuff made by Devcon/Permatex called Plastic Welder. It sticks air to water (almost) and works really well on resin hulls. It is also a bit thick and can be used to fill gaps and it is great fro repairs. It is also great stuff for building with.

[ghostofpf1]

I think I read somewhere that some polyester resins exude a form of wax or surface sealer while curing that helps the curing process somehow.I have had good luck reinforcing polyester resin glider fuselages with laminating epoxy and glass/carbon fiber by sanding and washing with alcohol but have not tried a boat hull as of yet
I also seem to remember that putting epoxy over cured polyester was more likely to stick than putting polyester over cured epoxy....

I also have a lot of grey hair and could be imagining all this .....

Thanks for the fish
Ghost

[Bill-SOCAL]

Wow, who still makes glider fuses out of polyester?? Any that I am aware of in the last 20 years or so are epoxy and glass.

[Jeepers]

I Plastic Welder. It sticks air to water (almost) and works really well on resin hulls. It is also a bit thick and can be used to fill gaps and it is great fro repairs. It is also great stuff for building with.

And it gives a really good buzz to!

Bill I dont know how stand the SMELL of that Plastic Welder!

[ghostofpf1]

Wow, who still makes glider fuses out of polyester?? Any that I am aware of in the last 20 years or so are epoxy and glass.

Many of the Chinese/ebay gliders are polyester/glass.I know the "Duo Discus 157" Sailplane" on ebay is poly/glass since I have one ... I have a Hobby Lobby scale glider that is polyester/glass..
Nothing wrong with polyester resin.They've used it for mass produced full size boat hulls for economy's sake (amongst others I suppose) and I suspect the same goes for the chinese planes and boats.I just think in thin sections it's a bit brittle.
Epoxy is more flexible though I think in it's cured state and probably better in flexure so maybe that's why the high end molded sailplanes use epoxy resin instead of poly.
Anyone know if the typical carbon fiber fabric we use is "sized" or treated for compatibility with poly resins ??
thanks
Ghost

[blakybob]

Hey Bill, I'm looking for a JB Weld alternative and this Devcon/Permatex Plastic Welder stuff sounds like it's just the ticket. Where can I pick some up? I've looked at Autozone, Pep Boys, Advance Auto Parts, and O'Reilly. Nobody's heard of the stuff.

Blake

[Eodman]

I'm pretty sure Ace Hardware carries it! Try Lowes or home depot!

[Bill-SOCAL]

I get it at Pep Boys. It is back with the other adhesives they sell, usually near the oil and stuff. I also get it at Ace True Value hardware.

I have purchased it at three different Pep Boys here in SOCAL.

Turns out that Tower sells it too:

http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXC032&P=FR

THis way you can see what it looks like. The Permatex package looks about the same

[ghostofpf1]

Just bought 3 tubes of devcon plastic weld at Orchard Supply ...

HTH
Ghost

[Stealth Assassin]

Well,,,, I have had good luck with epoxy bonding to polyester... Go figure! It has made some strong bonds for me and I have made several parts from molds.

That plastic weld Is some killer stuff though!

[blakybob]

Thanks Bill. I think I found the same stuff at Autozone but it's made by Versachem. I'll give it a shot in my DF33.

Blake

[ghostofpf1]

Just wanted to note that you can buy polyester resin and hardener at Home Depot (paint dept on the adhesives shelf) so no need to use epoxy over polyester if your not having good luck bonding the 2 with sanding and alcohol wash.
I just picked up a quart kit and will use it for my stuffing tube reinforcement as well as make a test strip with some of the carbon fiber I have to make sure it's compatible with polyester resins.
hope this helps
Ghost

[blastoff]

The parts I am bonding to the hull are epoxy. The bond between the epoxy based plate and the polyester hull makes for a very brittle connection or bond. It holds pretty good but under force it snapped, I like to give bonded parts a good load test before I glue all the other pieces together.
I never thought in a million years some one was still making polyester hulls. I wish I would of done more research before buying the hull. Oh well
I got a tube of Goo or what ever it is and several tubes of Plastweld, I should be doing some work on the project soon and will post the results.
Cheers

[Bill-SOCAL]

Either one (Goop / PlastiWeld) will work nicely. And it seems almost all hulls are polyester resin and glass. Very few epoxy hulls around.