Filling epoxy on vertical sections of deck

[cklanac]

Basically, I'm installing the portlights on our Morgan 43CC. The
thru-bolts which hold the portlight to the trim ring go thru
hollow area of the cabin 'wall'. There deck is cored on the
horizontal "deck" sections but not the vertical "wall" areas.

I want to create an epoxy filler similar to the way one would
for deck hardware. (e.g. drill oversized hole, fill it with
epoxy, then re-drill it). This will seal the bolts and
prevent portlights from simply crushing the deck and
headliner. But if I try to fill the area, the epoxy would
simply slide down inside the gap...

I'm looking for suggestions on either creating some type of
support for the epoxy or maybe creating little rods of epoxy
which I can insert. Anyone else have something similar or
have any suggestions?

-ck

[delmarrey]

You can add fillers to epoxy which will create a peanut butter consistancy. With that you can use a putty knife to squeese the stuff into where you want it. When it's thick enough that it doesn't run off the putty knife, with in two minutes, then it 'll stick to a vertical surface.

In your case you could drill the hole all the way thru whatever size the bolt is, then use a suringe or putty knife and push it in from both sides.

Tip: Once the stuff is fairly thick, put it on a flat plate and finish the mixing with a putty knife. This will help keep some of the bubbles out.

http://www.westsystem.com/

I use the 403 filler for most of my projects.........._/)

[Alan Wheeler]

OK here's a tip for ya all. When you empty a plastic cartridge of RTV or any other product that comes in the plastic cartridge, keep the empty cartridge. Put a rod in the end the nozzle end and push the cap back out the other way, right out of the cartridge. Now when you want to squeese that peanut butter like filler into an out of the way place, just fill the cartrdge and push the cap in and place it in the gun and away you go. I have just done it myself on a project, there I needed to get a thick consistancy of epoxy down a long enclosed groving in a timber frame. I pushed the stuff some 12 feet down a 1/4" x 1/2" groove. It took about 5 fills of the cartridge.

[By Invitation]

cklanac,

I would suggest the following - if I understand your question correctly. I am assuming from your decription that these are New found metal portlight's or similar to them. Once you drill the horizontal holes in your cabin sides, place plastic sheeting ( any thickness) on either side of the hole, clamp a piece of wood on either side to seal both sides. Now drill a very small hole vertically so you can inject the epoxy into your large hole, let it cure, remove the clamp, wood and plastic and sand smooth. Your hole is now filled and you can re-drill it.

[PM]

What your looking for is fumed silica, also known as aerosil and cabosil. This thickens the epoxy so it will not sag. A good filler I found is teak sawdust,aerosil and epoxy. I used this filler in the same way you intend. It sets hard and strong.

You can find this cheap at some auto-marine type outlets that cater to auto-body people. If you buy a name brand like WEST you'll pay10 times what it's worth.

[cklanac]

The problem is I'm trying to fill a blind 1/2" hole. I can't use a trowel or putty knife to push the thicken epoxy against the fiberglass. I need to push it into the hole. And without a core for support, the thickened epoxy simply falls down the space in globs or the stuff that does stick isn't consitent in thickness. This causes gaps.

However, I got a tip on another site that I thought I'd share...

Stuff a small strip of weather stripping into the hole, then using your finger or an allen wrench (if the hole is large enough) arrange it in the hole. Now pour or inject the epoxy mix into the hole... a ketchup consistency should fill the space nicely.

[BC Mike]

I have used the anti sag stuff with epoxy and the stuff still seems to sag. I have used duct tape to hold the epoxy in place, and removed it when the epoxy hardened.
Michael

[Alan Wheeler]

Yep I guess that's one way if you have the working room to get the weather strip in there CK.
Now without really knowing the setup you are workign with, here is another idea. Firstly, does it have to be epoxy??? Why not use that expanding Urathane foam in a can and squirt it into the hole, thus filling the void completely. Like make a foam core sandwhich, of which you can then cut, drill or what ever. If you really want to still put epoxy in the bolt hole, you can squirt some epoxy filler in the hole, before the Urathane foam has hardened and if will push out of the way, but still hold the epoxy in place.
Let us know what you do int he end and how succesful and/or difficult the job was.

[GordMay]

Wheels wonders: “... does it have to be epoxy??? Why not use that expanding Urathane foam ...”

The Epoxy "backfill" serves (at least) two functions:
1. It seals the cut edges of the fibreglass “skins”, and the interior core material against moisture/water intrusion.
2. It acts as “compression plate” to accept the crushing loads imposed by the fastenings.

I would not recommend the use of Urethane Foam, in this application - as it will perform neither of the above functions very well.

FWIW,
Gord May

[cklanac]

Alan, I considered the using spray foam...

I was going to spray the foam in and let it dry then cut it back the way your would a regular balsa core. Then create the epoxy plug. While it would work, I was warned that the foam can actually create a lot of pressure as it expands and may deform the headliner. I doubt it would effect the deck since it is fairly thick but the head liner might bulge. So I'm opting for the weather stripping...

It's my project for this weekend so I'll let ya'all know how it goes.

thanks for the help/suggestions.
-ck

[Alan Wheeler]

Just to reassure Gord, no I wasn't meaning the use of it as a sole filler, but as a means of filling the void enough to then apply the epoxy filler. Just as CK has thought of.
So CK, as long as you allow an escape path, ie the hole you are using to fill the void, to remain open, then any excess pressure will release back out that hole. Plus if the void is very large, then any foam pressure, will simply continue to expand and fill the void till the expansion runs out of "puff" so to speak. The stuff remains thick yet very movable and forgiving untill the cureing process starts, as to which time the expansion process has already finished.

[dkall]

Since it is hidden by the flanges, drill a 1" hole all the way through. Fill a 1" id hose thickened epoxy and let it kick. Then saw it into pieces the same thickness as your cabin sideliner is. Now make up some more thickened epoxy and epoxy the plug into the 1" hole. Redrill for your ports and now you have solid bearing surface to bolt to.

[Rick]

This problem is usually solved by using MarineTex which is a thick epoxy that has great machineability and compressive strength. On a vertical surface I notice that there will be a slight sag as it sets up yet if you babysit the hole testing for viscosity increase as it "kicks" then you can make the hole relatively flush by pushing the epoxy flat just as it gets hard.
Rick

[cklanac]

Well I got so many good suggestions, I decided to try them all... here are the results so far.

The spray foam worked but it had it's issues. I sprayed it into the holes and gaps and let it expand. I used C-clamps around the openings to keep it from bulging the headliner. After cutting is back there was residue left on the fiberglass which would have prevented the epoxy from getting a good hold. So I took a wire brush and cleaned off what I could... It was a very time consuming exercise but it worked fairly well.

On some holes I tried simply injecting epoxy thickend with filler. If the gaps between the headliner and hull was greater than a 3/4" then the epoxy would slide down the inside of the gap. On some holes I filled it 3 or 4 times before getting a proper set. I had better success with 407 Low Density filler which is lighter/fluffier than 404 High Density filler. This method used more epoxy (which isn't cheap) but was effective.

On some areas I shoved pieces of foam into the hole, then injected the thicked epoxy like before. This worked particularly well if the gap was greater than 3/4" where the epoxy had a hard time supporting itself. This was tedious but more easier than epoxy alone and not nearly as messy as the spray foam.