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Dumb question #247...

I need to fill a couple of holes in the vertical sides of my hull..

The largest is about 5" high and 12" long...

I have read the info about the beveled sides needed, the layup schedule, the materials needed, etc.

What I can't figure out is how to lay up the epoxy wetted glass cloth on a vertical surface so that it does not slide down before it cures. I suppose it is possible to use thickened epoxy, which I do often in other types of repairs, but this fights the glass cloth wetting out process. I have come up with a couple of ideas, but none seem practical. So guys.. how to do this?

Frank,

All about weight and gravity...

You may need to reduce the number of layers per layup so that the weight doesn't overcome the frictional tendancy of the layup to the point that gravity takes effect.

Keep your epoxy to glass ratio just to point that the glass is wet, but not skating on a slick film of free resin. A very small amount of cabosil will help, but not so much as to hinder the wetting effect to the glass.

Do two layers, allow it tack up before doing the next two layers. Once you get the hang of it, you can even glass upside down.

Don't work with epoxy in direct sunlight. The heat will thin the resin and further aggrivate the gravity problem.

Thanks Capt Pat...

I am using MAS Epoxy "FLAG" (Filleting, Laminating And Gluing) resin, which is a little thicker than their regular resin, and thought that would solve the problem, but the cloth still slides. I will cut back on the resin loading and give that a shot. I am working indoors so the sun isn't an issue.

CaptPatrick wrote: Do two layers, allow it tack up before doing the next two layers. Once you get the hang of it, you can even glass upside down.

Oh God!!...one cannot fathom the mess I would make attempting that maneuver.

Capt Pat,
This weekend I will attempt the upside down manuever. Any tips are welcome. I'm having to re-core the stbd gunnel where my vents, outrigger, water fill and fuel fill holes are cut. The 3/4 inch ply under the top-cap glass was mush. I cut it out and have it down to the thin glass top side. I am using West System. I plan to mix up some cabosil with 105 & 209 (slow hardner) and coat/trowl the putty to both the underside of the gunnel and my new, pre-coated epoxied 3/4 marine ply with all cutouts already done. I will use the same screw/bolt holes on the top side to screw into the new core to bring the two together.

Once dried, I then want to glass over the bottom side of the new core. What type of fabric would you recommend? Should I use 105 & 205 (fast hardner). I must say that fast stuff really kicks quick... I tried using it this past weekend for some parts layup and the stuff gelled in the pot in about 5min. Will this fast hardner help with the upside down manuever? Thing I've found is when it kicks... it's a pain to deal with.

I'd also suggest that after it dries, you withdraw the screws, drip some epoxy into the holes and replace the screws just in case water finds it's way down to the core of your epoxy covered plywood.

Capt Pat,
This weekend I will attempt the upside down manuever. Any tips are welcome. I'm having to re-core the stbd gunnel where my vents, outrigger, water fill and fuel fill holes are cut. The 3/4 inch ply under the top-cap glass was mush. I cut it out and have it down to the thin glass top side. I am using West System. I plan to mix up some cabosil with 105 & 209 (slow hardner) and coat/trowl the putty to both the underside of the gunnel and my new, pre-coated epoxied 3/4 marine ply with all cutouts already done. I will use the same screw/bolt holes on the top side to screw into the new core to bring the two together.

Correct move. Remove the screws after the epoxy first kicks, but not longer than 8 hours from when it was applied. Allow the epoxy to fully cure and then re-install the screws, other wise you'll never be able to remove them...

Once dried, I then want to glass over the bottom side of the new core.

Do that before you laminate the core under the gunnel... No upside down glassing need then.

What type of fabric would you recommend? Should I use 105 & 205 (fast hardner). I must say that fast stuff really kicks quick... I tried using it this past weekend for some parts layup and the stuff gelled in the pot in about 5min.

Never use West's fast hardener, it's way too damned fast!

Thanks Capt Pat. Will do. Yea, that fast stuff is just too quick. First batch I read it wrong and mixed abou 150 ml at 5:1, instead of 3:1. While I was mixing it it started to gell and then started smoking. Had to just put the jar down and watch it melt. Glad no one was around to laugh at me.

Capt Pat & Walter,
I can't thank you enough for your advice. Completed the upside down manuever on Sunday. OMG what a mess. I did as you instructed.

I made a top-side "mold" out of 6mm plywood and then glued wax paper to it using 3m spray glue. I drilled holes through the top-side ply to line up with the pre-drilled holes in the deck and new core (which was pre-expoxy/glassed). I then wet down the underside of the deck and new core and mixed some cabosil/epoxy. Then the fun part of spreading the goo with a notched trowl to the underside of the gunnel and the top side of the new core and holding it in place to drop in my bolts and screws. Good thing I had lined the entire cockpit with drop cloth! I had epoxy everywhere... btw, how do you get it out of your hair!

Good thing I listened to you and pulled the screws and bolts out after it started to kick. The last to bolts took a hell of a lot to pull out. I removed the wax paper lined top-side ply and all the extraneous holes wer beautifully filled. No epoxy on the top-side... looks great!

Thanks again.
Paul J.
1973 B28 - PALADIN

btw, how do you get it out of your hair!

Speciality tool: Scissors

(been there done that...)