Keyboard Shortcuts
ctrl + shift + ? :
Show all keyboard shortcuts
ctrl + g :
Navigate to a group
ctrl + shift + f :
Find
ctrl + / :
Quick actions
esc to dismiss
Likes
Search
Re: Leak at traveler - minifish
|
Charlie,
toggle quoted message
Show quoted text
I've gotten polyester resin and hardener at many hardware stores as well as boat stores. Beware using non-marine polyester filler, but the resin is fine. Both epoxy and polyester have their advantages and disadvantages. I prefer, in general, to repair polyester boats with polyester resins so as to not create problems for future repairs. As you note, polyester will not adhere to epoxy. In fact, polyester isn't really an adhesive. It forms a mechanical bond with the cured resin. This is why it's important to rough sand a taper around the hole, at least 3 inches, to give a good bond. When patching, I like to lay up all layers in one day, without letting the resin completely cure between layers. I let them kick off and become hard, but the next layer can still chemically bond, saving some sanding and probably giving a stronger layup. BTW, if you let epoxy cure, you need to wash the amine blush off with soap and water, and then dry the surface, before continuing. Polyester is air-inhibited, so the surface will not cure completely in the air. That's why very thin applications don't work very well. The normal way to get the surface to cure is to coat it with PVA (poly-vinyl alcohol). On small boat repairs, I typically just sand it smooth and spray it with appliance enamel. Polyester gives off a lot of styrene, which is what you smell. If you're working indoors, use a respirator. If you're working with large quantities and frequently, use a respirator. If you're patching a Sunfish outside, the fumes will likely blow away. Prefer working from the windward side, and hold your breath for a moment if you smell it. I have a respirator but no longer use it when doing small patches like this. When I do use it, I load my beard up with glove-cote to seal the airflow around the respirator. I've done a lot of repairs on Sunfish and other small boats when my grandkids were in a junior sailing program. Kids are hard on boats, and they often need patches. The method of working outlined in emerged from that. It will not give the most pristine results, but they will be reasonably good, strong, and functional. If you're working on a show-quality boat, you'll want a seasoned professional working on it. The biggest resin job I've done was helping a friend replace the rotten plywood deck of his 21' center console with Coosa board covered with glass. Another friend was mixing the resin for us as fast as they could, and we went through several gallons on one hot afternoon. That was about 20 years ago and that boat is still rock solid. I've also done a lot of deck re-coring on my Alberg 30, also with polyester. That requires a little more care than the small boat repairs. When I repaired the forward edge of the bow, I used epoxy because I was concerned about getting enough grip across the width with the polyester. But otherwise, I've used polyester and have no trouble getting insurance. Oh, epoxy resins have remarkably different characteristics depending on trace amounts of additives in the resin and/or hardener. I had a great conversation some decades back with the chemist for a boat builder who built with epoxy. That chemistry is not for amateurs like me. It's also a warning that not all epoxies are alike. Use what you want. I'm not interested in re-engineering an old Sunfish, so I use what's worked for it it's whole life. - George On 7/6/20 5:52 AM, Signal Charlie wrote:
Hey George --
---------------------------------------------------------------------- When I remember bygone days George Dinwiddie I think how evening follows morn; gdinwiddie@... So many I loved were not yet dead, So many I love were not yet born. also see: 'The Middle' by Ogden Nash ---------------------------------------------------------------------- |
to navigate to use esc to dismiss