RESINS...

[oldlugs]

Hey gang, I'm wondering about which types of resins are best used to repair which hulls...

If I have a hull built with "vinylester" resin, should I only be using that same type of resin to repair with, or glass in a stuffing box? Would regular polyester resin work just as well on a vinylester hull? How about vinylester resin on a polyester hull?

I know I can use epoxy on either, but doesn't it work best on epoxy hulls?

The reason I'm asking, is 'cause I bought a used 20 size Microburst off eBay (supposedly in very good condition....) that had an electric motor mount poorly installed with CA and epoxy and some white goo...and some brown goo... The original composite stringers look decent, and I want to run it with a .21 in there, so out came all that old crap, leaving only the stringers. After lots of scraping, grinding and sanding, it'll be ready for for a new stuffing box. I'm guessing that even though it's an early Microburst, it may be vinylester/glass, and I want to recondition it with the best possible, most appropriate materials... Hard to be proud of an ugly boat; right?

Thanks for any advice (short of saying, "just buy a new hull"...).

Duane

 

[Xtremarine]

Im building a mold and plug and I use west systems.. its alittle pricey but its suppose to be the best ( the orange stuff is spot putty I had alot of air bubbles ...my first mold...

OH THATS THE WWW.XTREMARINE.COM SERVER W/FAT FRACTIONAL T1

 

[oldlugs]

Groovy server and mold, but nothing to do with the resin compatability question... Something like me posting a picture of my orange tree on a piston and sleeve thread...

Anyway, I guess I'll just use vinylester resin on this Microburst, assuming that's what it's made from. Can anyone confirm vinylester on what I'm guessing is an early Microburst? The forward deck resembles a Youngblood's; not concave like current Microburst, and the keel is rounded, not sharp.

 

[Xtremarine]

Groovy server and mold, but nothing to do with the resin compatability question... Something like me posting a picture of my orange tree on a piston and sleeve thread...

Anyway, I guess I'll just use vinylester resin on this Microburst, assuming that's what it's made from. Can anyone confirm vinylester on what I'm guessing is an early Microburst? The forward deck resembles a Youngblood's; not concave like current Microburst, and the keel is rounded, not sharp.

lol I am totally lost with what your saying Im no Glass guy as you can tell by all the spotputty in my mold lol

But hang in there some 1 here knows..I just needed a place to show off my first mold(poor) attempt

 

[dannyual767]

Duane, I'm not really sure about that vinylester stuff but polyester resin is what you usually find in Walmart, Home Depot and Lowes. It does work good on polyester hulls. I've been doing some overhauling on an older Aeromarine Avenger hull and polyester resin and glass cloth has been working real good !

I'm going to assume that it will work well on your vinylester hull, too.

None of this means that I'm a polyester resin guy! I'm a firm believer in epoxy resins and thats all I use these days when I'm working with wood boats !

You can use epoxy over polyester but if you try to put polyester over epoxy.........well, bad things can happen (but I haven't gone there to test this myself!)

 

[RCUK John]

You could take a look at http://www.intlwaters.com/index.php?showtopic=14216 which was on Finishing Resin.

Look at http://www.cfsnet.co.uk/ for some reading - this was referred to in that thread.

John

 

[Mike G]

You can use epoxy over polyester but if you try to put polyester over epoxy.........well, bad things can happen (but I haven't gone there to test this myself!)

Something about the Animine (sp) in the Epoxy pulls the hardner out of the poly resin mix. As soon as this was explained I stopped trying to do it! :lol:

Epoxy over poly is a mechanical bond, only as strong as the epoxy itself, Vs a chemical bond such as a poly over poly repair where the new poly actually bites into the old poly surface.

Not an expert by any means but I have been building my own hulls for about 3 years. Living in a small town makes for a lot of trial and error!

 

[ids987]

You can use epoxy over polyester but if you try to put polyester over epoxy.........well, bad things can happen (but I haven't gone there to test this myself!)

Epoxy over poly is a mechanical bond, only as strong as the epoxy itself, Vs a chemical bond such as a poly over poly repair where the new poly actually bites into the old poly surface.

I keep seeing conflicting opinions on this. One school of thought says that poly to poly only forms a chemical bond if the base poly has not cured, and that as neither epoxy nor poly will form a chemical bond with cured poly, the epoxy, having generally greater strength and adhesion, will form a stronger bond. The other says that poly to cured poly does form a chemical bond, and is therefore stronger.

I'm about to start building a poly boat (one day, when I have the time), and would like to put the shaft, engine mounts etc in with epoxy, if it will work - for the lightness etc. Has anyone tried this ? To quote a theme, enquiring minds........

Ian

 

[Mike G]

Ian both saying are correct to a point. A lot of Poly resins have wax in them, it floats to the surface and keeps the air out while the polyester resin cures. So if you want to add another layer after it is cured you must sand through the wax to get to the straight poly underneath. Once you have done that it will soften the top of the cured resin. If you have a 1/16" thick boat and try to add a 1/4" layer of mat on top it will warp the crap out of your hull, so a little common sense is also required.

I do stuffing tubes with Epoxy in Poly boats all the time, holds forever but it is removable if you need to change.

 

[ids987]

Ian both saying are correct to a point. A lot of Poly resins have wax in them, it floats to the surface and keeps the air out while the polyester resin cures. So if you want to add another layer after it is cured you must sand through the wax to get to the straight poly underneath. Once you have done that it will soften the top of the cured resin. If you have a 1/16" thick boat and try to add a 1/4" layer of mat on top it will warp the crap out of your hull, so a little common sense is also required.

I do stuffing tubes with Epoxy in Poly boats all the time, holds forever but it is removable if you need to change.

Thanks Mike - much appreciated.

Ian

 

[gil sonsino]

Hi Duane

Both vinyl & poli resins work between once they use the same base catalist(MEC).You can't go wrong but just take your time cleaning very well the surfaces ..you can use a good degreaser for that.As previouly mentioned take care with the amount of glass you will apply to avoid further deformations due to the resin contraction.

Good boating

Gill