´95 Scarab 22 Re-Rig
#14
Registered
Thread Starter
Join Date: Feb 2004
Location: Vienna/Austria
Posts: 70
Likes: 0
Received 0 Likes
on
0 Posts
Re: ´95 Scarab 22 Re-Rig
Ok, next was getting the old anitfouling paint off. Antifouling is very common in europe since most boats stay in the water for the entire season, without protection you need a lawn mower to get it clean again...
This stuff was totally dried out, however, and came off fairly easy by scraping. In the more stubborn areas, we used acetone sprayed on, covered it with plastic film (like the one you would wrap your leftovers in) and let it soak for 5-10 minutes. This will penetrate the old paint so it can be wiped or scraped off.
This stuff was totally dried out, however, and came off fairly easy by scraping. In the more stubborn areas, we used acetone sprayed on, covered it with plastic film (like the one you would wrap your leftovers in) and let it soak for 5-10 minutes. This will penetrate the old paint so it can be wiped or scraped off.
#15
Registered
Thread Starter
Join Date: Feb 2004
Location: Vienna/Austria
Posts: 70
Likes: 0
Received 0 Likes
on
0 Posts
Re: ´95 Scarab 22 Re-Rig
Time to assess the damages to the gelcoat and the laminate. What i found was again due to stress (like cracks where the stringers meet the bottom of the hull. IMO, that comes from the bottom not being sufficiently supported by the trailer where the weight of the engine sits. go over a bump too fast and the momentum of the engine will cause cracks in certain areas. And there´s jumping the waves, of course).
However, there were also some more issues on build quality, like where the strakes sit. Lots of air bubbles in the gelcoat and very uneven lamination.
the first picture from the rear shows how thin a layer of chopped strand mat was covering the core, so thats where lots of spider cracks appeared.
However, there were also some more issues on build quality, like where the strakes sit. Lots of air bubbles in the gelcoat and very uneven lamination.
the first picture from the rear shows how thin a layer of chopped strand mat was covering the core, so thats where lots of spider cracks appeared.
#16
Registered
Thread Starter
Join Date: Feb 2004
Location: Vienna/Austria
Posts: 70
Likes: 0
Received 0 Likes
on
0 Posts
Re: ´95 Scarab 22 Re-Rig
More...
The second pic shows the largest defect; also, reason was too thin outer laminate over the core. from the outside, there were spider cracks, and when i started to grind the gelcoat off, thats what finally came out.
The second pic shows the largest defect; also, reason was too thin outer laminate over the core. from the outside, there were spider cracks, and when i started to grind the gelcoat off, thats what finally came out.
#17
Registered
Thread Starter
Join Date: Feb 2004
Location: Vienna/Austria
Posts: 70
Likes: 0
Received 0 Likes
on
0 Posts
Re: ´95 Scarab 22 Re-Rig
Spider cracks were ground down into the laminate with smooth bevels to the gelcoat, then filled with epoxy mixed with chopped fibers and covered with light weave glass (80grams). Then sanded flat and filled with epoxy putty (the grey stuff) and sanded again. unfortunately, I didn´t take the opportunity to actually blueprint the running surface of the boat.
#18
Registered
Thread Starter
Join Date: Feb 2004
Location: Vienna/Austria
Posts: 70
Likes: 0
Received 0 Likes
on
0 Posts
Re: ´95 Scarab 22 Re-Rig
Then came my first mistake, caused by inexperience.
I tried to roll on the first layer of the new gelcoat. Don´t do that.
Rolling it on has several disadvantages:
1) it takes too long. I threw away a 2 pound brick of smoking hot gelcoat.
2) it is too uneven and too thin. What means a lot of sanding
and also with the material i used, most of the material could be wiped off and it had to, as it was sticky and didn´t allow the next layer to be applied right away (because of the wax rising to the surface).
So most of it was removed again and left this surface
I tried to roll on the first layer of the new gelcoat. Don´t do that.
Rolling it on has several disadvantages:
1) it takes too long. I threw away a 2 pound brick of smoking hot gelcoat.
2) it is too uneven and too thin. What means a lot of sanding
and also with the material i used, most of the material could be wiped off and it had to, as it was sticky and didn´t allow the next layer to be applied right away (because of the wax rising to the surface).
So most of it was removed again and left this surface
#19
Registered
Thread Starter
Join Date: Feb 2004
Location: Vienna/Austria
Posts: 70
Likes: 0
Received 0 Likes
on
0 Posts
Re: ´95 Scarab 22 Re-Rig
So I got me a gelcoat gun to spray it on. That was a better way, sort of.
It produces a much smoother but by far not really smooth and flat surface, rather like spraying underbody coating on (the material was pre-fabricated for spray application, before anyone asks). So that meant, yes, more sanding
It produces a much smoother but by far not really smooth and flat surface, rather like spraying underbody coating on (the material was pre-fabricated for spray application, before anyone asks). So that meant, yes, more sanding
#20
Registered
Thread Starter
Join Date: Feb 2004
Location: Vienna/Austria
Posts: 70
Likes: 0
Received 0 Likes
on
0 Posts
Re: ´95 Scarab 22 Re-Rig
However, gelcoat (or at least this material) is supposed to be sprayed into a mold; if you spray it ONTO something, as it cures, the waxes in the material which are responsible for producing a dry and hard surface (in the mold), rise to the surface and leave the whole thing sticky as hell. Has to be washed off with solvent before you can sand it, since it will clog your sanding paper in seconds.
However, after washing it and then sanding it with 120, 220, 400 grit and then 800 and 1000 wet paper, and polishing it (even more ), the finish was quite ok (not sure if it comes out well in the pic).
The white stuff is an epoxy primer as an osmosis protectant before the new antifouling paint comes on.
However, after washing it and then sanding it with 120, 220, 400 grit and then 800 and 1000 wet paper, and polishing it (even more ), the finish was quite ok (not sure if it comes out well in the pic).
The white stuff is an epoxy primer as an osmosis protectant before the new antifouling paint comes on.