Re: [capri26] Gelcoat cracks - Part Deaux...
On 8/12/2012 1:33 PM, Richard wrote:
I'm still working on it, Gary.
Let me see how much of this is necessary before you get started.
That part is done...
I'm not going to use the islands/pads that I made unless the surface cracks reappear
after I get her back in shape.
I want to try this simpler repair to see how well it works first.
For fairly fine or short cracks in the core material:
Drill small passageways (12 inch long 1/8" dia bit)
The long bits are necessary to get access to "edge drill" inside the slot and bolt holes.
From the top, drill along the path of the crack roughly 1 to 1-1/2 inches deep.
This hole will be at an angle, so be be careful not to drill through into the cabin liner skin!
If you can see multiple paths drill each of them.
For lack of a better term, call these the "caverns".
Also drill a 1/8" "vent hole" near the far end of each cavern.
It will probably be out from under the chainplate fitting, and will show some.
But you will need the vent.
Tape the underside of the slot and bolt holes with plain old duct tape.
Be very careful that there are no creases in any of the edges to avoid leaks!
(note: I also put a Mr. Clean Magic Eraser on a small plywood support and shimmed
a stick under this to the setee. That made a really secure seal and gave room to carve the
slot and bolt holes later on)
Mix up resin and fill the cavities - slot and bolt holes - until resin comes out of the vents.
I would suggest a low viscosity resin for this - EpiBond, for instance.
I've used it many times and appreciate the thinner consistency for this job.
I used "penetrating resin" from West marine, but it didn't cure the way I expected.
It was very rubbery after the cure. I'm thinking it had to be a bad mix, because I've
used this stuff before and it has always cured hard. But this time it didn't.
Like i said, probably a bad mix. I have caught myself a couple of times mixing up
little details like that since that last mini-stroke. Guess I missed that time.
SO....Deaux munber two
I redirilled the passageways with a 3/16" bit this time (for the thickened resin)
and redrilled the vents 1/8" again (same places).
Then INJECTED West System 6-10 resin into the cavities.
6-10 is pre-thickened and comes in a caulk tube type dispenser.
It has replaceable "mixing tips" that screw on to the tube.
Pretty neat trick! Just squeeze it out and it mixes the right ratio in the tips.
I injected the resin into the 3/16" cavities, and until it ran out the vent holes
Then back-flowed from the vents into the 3/16 holes into the slot.
The results were very satisfying. Very good fill in all the cavities.
And the resin kicked off properly.
I drilled the bolt holes (5/16") and each end of the slot (same) then used the
Dremel MAX saw blade to cut the long sides of the slot loose.
That pops the plug out of the slot and makes a nice proof coupon.
So next was to fix the surface cracks in the get coat.
I'll try this one again too. I think the mix was a little hot and it was a
fairly warm day. So it has some texture (internal bubbles?).
And maybe add just a little touch more white?
Anyway, It's about done.
2 or 3 hours including the redeaux.
Should be simple enough for DIY or a fairly cheap repair via the yard guys.
- I checked. No photos of the chain plate fitting in place.
So I went and looked up the drawings.
Mow I'm really not sure.
The attached is part of the Mast Rigging drawing (260-38006-0)
The drawing part is clear enough.
But the words....
AFT lower shroud
chainplate is FWD
and angled inboard.
It's the forward tab they are talking about?
Spreader sweep would put the aft tab straight up, right?