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preventing epoxy runs in CB trunk

PostPosted: Sat Mar 15, 2014 7:54 am
by DanaDCole
Has anyone come up with a brilliant idea to prevent accidental epoxy runs into the trunk when applying fiberglass? I'm a long, LONG way from needing to know this (still working on side panels prior to constructing cradle) but wanted to ask while it is still on my mind--also it might be useful to others. I know that no matter how careful I am sometimes the epoxy runs over the edge and at that point there would be no way to get at it to clean it up (even if you knew about it). Epoxy runs inside there would screw things up forever.

My first thought is to carefully cut a one-inch thick block of foam to exactly fit the hole. A piece of clear packing tape on the top edge of the foam would keep the epoxy from sticking to it (which it may not anyway). But even if the epoxy did stick to the foam it wouldn't matter. When the rectangle of fiberglass is cut out, the foam would just come out with it. Also, I think the foam should be long enough to reach all the way down to the top of the trunk to keep it in place. The rectangle should not be cut out and removed until all epoxy coats are in place. (It might be a good idea to leave the foam in place to prevent paint from running down in there later. That could also gum up the works.)

Any better ideas?

Re: preventing epoxy runs in CB trunk

PostPosted: Sun Mar 16, 2014 5:24 pm
by truenorth
I didn't have a problem with epoxy runs in the centerboard trunk. I'm not sure what causes your concern?

The only times I had to be extra careful was when installing the cleats that run on either side of the trunk, and when I filled the hole that would serve as the output for the pendant line. In the first case, I put masking tape along the inside of the trunk just in case it ran over (it didn't). For the hole, I put a good size bit of tape as a backer and took care not to overfill the hole. A syringe worked well here.

Later, the manual notes you will put a strip of clear tape along the top when installing the deck. But until then, all the 'glassing and epoxy work stays well away from the trunk. Keep the drips away and there's no risk unless you trip or something with a bucket o' epoxy. Alternatively, you can just put a strip of clear tape along the top now if you want to be extra careful.

Re: preventing epoxy runs in CB trunk

PostPosted: Sun Mar 16, 2014 10:14 pm
by DanaDCole
Truenorth,

Thanks, but I guess I'm a worrier. As I understand it, the cloth has to be wetted out right up to the rim or edge of the trunk. At the very least, you need plenty of epoxy there to protect the wood from water infiltration. It looks like an accident waiting to happen, but maybe I'll see it differently when I get there.

I read about the tape on top of the trunk earlier. You definitely need the tape there because you are gluing the cap on blind, and there's always squeeze-out when gluing.

Anyway, thanks again. It I still don't trust myself when the time comes, it won't be hard to add some kind of protection, just in case.

Re: preventing epoxy runs in CB trunk

PostPosted: Sun Mar 16, 2014 10:31 pm
by truenorth
The outside of the cb trunk is not 'glassed except when you do the floor installs, so the 'glass only goes up a few inches from the bilge. That said, you can do as much 'glass as you want, but it's not called for in the manual. I'd say no for a few good reasons.

It gets the usual epoxy treatment, though. I epoxy'd and (mostly) sanded mine on the bench to save the headache later. With care, it's not a problem. You also will have cleats at the very top 1". This, I think, presents the greatest risk of mucking up the insides. But hey do what you gotta do.

Re: preventing epoxy runs in CB trunk

PostPosted: Mon Mar 17, 2014 7:04 am
by DanaDCole
It looks like I did not make myself clear in the original post. I am talking about fiberglassing the hull after the boat is turned upside-down. That is what I am concerned about. I am worried that when I try to get the cloth "wetted out" as close as possible to the trunk I might slop some over the edge. At this point, I am having difficulty seeing how this can be accomplished without causing runs, although obviously plenty of people have managed it.

Re: preventing epoxy runs in CB trunk

PostPosted: Mon Mar 17, 2014 1:14 pm
by Shudoman
When you epoxy the bottom of the hull the fiberglass spans over the slot and you apply epoxy over the entire hull including this area which has a double layer of fiberglass if you do it as per the instructions. Apply the first coat of epoxy thinly (as you should) and this area will be sealed against subsequent coats. Then after all epoxy coats are in place simply cut out the hardened fiberglass with a sharp box cutter. I used Trilux on the bottom and it is thick enough that you would have to really slosh it on to get it to run into the slot.

Bill

Re: preventing epoxy runs in CB trunk

PostPosted: Mon Mar 17, 2014 1:51 pm
by Diving Duck
Got it. Thanks!