Jackhammer: While you are correct Epoxy does have the ultimate in holding power it can cause problems down the road. For example putting ANY polyester paint over the top of it is a no no. So once you put the Epoxy down you have to treat it with Durratech and so on. Vinnylesters are very close in strength but do not have this problem. I think that what Glass Dave is saying is that if you properly prepair and mix your Polyesters and vinnylesters that they are more then addaquate. A lot of the bonding issues that people have are poor prep. I had to reglass a foot throttle on my buddies boat that he glassed down. He did it with epoxy and I just reached under the dash and ripped it out. I redid it with Polyester and you will rip a hole in the bottom of the boat before you have a problem with that thing lifting off again. A lot of people mix the ester resins to hot. The more layers you plan on putting down the hotter they will flash (actually goes for epoxy as well). So you do not want to over catalize your mix. I only ever mix up 1 qt at a time. This gives me plenty of work time for what I have in the cup and it never has haddened on me before I have had time to finish the area that I am working in. You need to work fast even with a quart.

Wetting out is when you apply the resin to the glasss it turns clear. What I always do is take a piece of cardboard or wood and put resin on the cardboard then I lay the strip of glass on the resin. I then take my paint brush and paint the glass. It will turn clear when you have the proper amount of resin on it. Epoxy is much harder to get the glass to go clear so you have to work it a LOT more. I then lightly squeegee the glass and lay it in the boat and do any needed touch ups.

Jon

Good post Jon... it's sharing this kind of real world experience that keeps me glued to OSO (almost a good pun : )

My post on epoxy was meant to to help superwrench decide if he wanted to spend extra on West Systems or not. John Greer will tell you pretty much all of the companies selling epoxy are esentially buying them from the same manufactures, Dow, Shell, vantico, etc... The only thing I really like about West is that they are stocked locally in the case I need a quick fix. When I was needing a lot for my project I actually went straight to Shell (driving distance for me) and was able to get what I needed to blend the 635... I just didn't need 55 gallon drums of it so I started buying from US Composites, they had the best prices...

is also a good site. They can provide conversion charts to let you know how much resin and cloth is needed to obtain the thickness you are after. If they can't, call Rick Hess at Composite's One. He can also provide a chart to get an idea for what you need. As far as poly, West or others? done right all work well. After 23 year I have never had a lay up let loose or delaminate. Used them but on large jobs your better with something that wets out quick. As stated grinding is a large part of the repair proccess.

Billy