Gel coat crazing

  • Thread starter Former member 63608
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Former member 63608

Thanks Peter and Trevor for your advice on the gelcoat crazing
problem. I just posted four photos of the crazing - see album "Gelcoat
Crazing"The best photo that shows the extent of the problem is the
cabintop. It is quite apparent and rather severe. If you look
carefully at the photos below the waterline, you can see the crack
pattern. I find it hard to believe that stress to the hull created
these; I am more prone to believing that they are the result of
gelcoat applied too thickly at the time of layup, effected by many
freeze/thaw cycles over the last 37 years. It seems to me that the
cure would be to strip the boat of all fittings and old coatings, dry
it thoroughly, fill the cracks with modified epoxy, fair, and then
paint the entire hull. I'd welcome all opinions on how to properly
correct this problem to restore the
integrity of the hull. By the way, the interior does not show any of
this external damage. I crawled through it from stem to stern.
Thanks, Dave
 
T

trevy_kins

.
Oct 31, 2019
230
Dave, where can I get some of that snow? Nothing but rain here in
Toronto. Hard to see the cracks in your photos. Looks like you'll need
to strip the bottom to determine the extent of your problems if any. As
for the cabintop, you may have had water enter into the core under
improperly bedded rails. I am going to remove all of my deck fittings
this spring and create over-sized epoxy plugs under the outer skin
through which to drill and re-bed the fittings afresh. Have you seen
how this is done? Trev.

________________________________

From: AlbinVega@yahoogroups.com [mailto:AlbinVega@yahoogroups.com] On
Behalf Of dave
Sent: December 21, 2006 9:55 PM
To: AlbinVega@yahoogroups.com
Subject: [AlbinVega] Gel coat crazing
Thanks Peter and Trevor for your advice on the gelcoat crazing
problem. I just posted four photos of the crazing - see album "Gelcoat
Crazing"The best photo that shows the extent of the problem is the
cabintop. It is quite apparent and rather severe. If you look
carefully at the photos below the waterline, you can see the crack
pattern. I find it hard to believe that stress to the hull created
these; I am more prone to believing that they are the result of
gelcoat applied too thickly at the time of layup, effected by many
freeze/thaw cycles over the last 37 years. It seems to me that the
cure would be to strip the boat of all fittings and old coatings, dry
it thoroughly, fill the cracks with modified epoxy, fair, and then
paint the entire hull. I'd welcome all opinions on how to properly
correct this problem to restore the
integrity of the hull. By the way, the interior does not show any of
this external damage. I crawled through it from stem to stern.
Thanks, Dave
 
P

pjacobs55

.
Oct 30, 2019
1,459
Dave,
I agree with your assesment of the problem ... definately a
manufacturing problem. It's probably not affecting it structually.
A repair job would be VERY labour intensive, and there is always the
possibility of the cracks showing through again after a couple of
years.

My personal opinion, and I emphasize 'personal', would be to look
for a boat in better cosmetic shape, even if it needs other work.

Best of luck, whatever you decide!

Peter
#1331 'Sin Tacha'
 
P

pelagicasd

.
Jan 28, 2001
694
Hi All. Just thought I'd talk about the crazing problem as Lyric has them
also. When I first purchased her there were some severe spider web type
cracks in the gelcoat by the forward bulkhead. Surveyor thought the bulkead
fitting might have been loose. I tightened everything up, dremeled out the
cracks and filled them with cabosil/epoxy. Never had another problem with
them. Have had continuing problems with the toe rails and cabin/deck. Did
the same treatment and watched new ones develop later. Below the waterline
the crazing is to much to contemplate dremeling. We didn't discover it until
we used peelaway to remove the numerous coats of bottom paint. We did a
barrier coat and again watched new cracks develop. I think the only way to
deal with this would be to put a whole new layer of glass cloth down.
Probably not needed as it doesn't appear to be structural. Water doesn't
leak in although some of them seem to weep a brownish residue.

Oversize epoxy plugs are easy but time consuming. Use a hole saw to cut
through the upper layer of glass (glase?) and core. this will leave a pilot
drill hole in the interior layer of glass. Put a piece of tape over that
hole from underneath. Put a drop or two of epoxy on the tape from above and
let it cure. Epoxy heats as it cures. If you were to try and fill the hole
without sealing it first the tape would let go when it warmed and the epoxy
would leak through the lower hole. Learned that one the hard way) Fill the
hole in small increments, maybe 1/4" or (6mm for the more sensible portion
of our community, wow a Yank that speaks metric!) if you were to try and
fill the hole on one fill the epoxy would boil and you'd have a closed cell
sponge in it. (learned that one the hard way also)I also used cabosil to
thicken the epoxy for this. Drill through it and bolt whatever down. It
won't compress.
Good luck, Walt

PS. Steve, thanks for the postal info!
 
P

pelagicasd

.
Jan 28, 2001
694
I should have added. A nice thick epoxy plug still needs a good backing
plate. I should also have added that Cabosil is colloidal siica. Essentially
powdered rock (granite). Don't be tempted yo use sand as you will not be
able to drill through it withour ruining the drill bit. Walt
 
T

trevy_kins

.
Oct 31, 2019
230
Thanks for instructions on epoxy plugs, Walt and Judy. Just one question -- how did you refinish the surface after installing the plugs and filling the cracks etc. Did you paint your deck or touch up with gel coat? Cheers, Trevor V2915
 
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