Have now filled my tired hulls with whats seems like gallons of epoxy. Now for sanding the gelcoat.
How far do I take it down without making the structure weak? There will be exposed glass in some places due to warpage and high spots from the epoxy fill, but do I have to remove all the gelcoat?
Have Interlux Brightside paint and primer on order. Have used this paint on many kayaks and dingys I have built and it always looks great if you tip it correctly. I know wood (in a non gay way) but have never dealt with fiberglass and gelcoat.
Bobby
Sanding Gelcoat
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Posted: May 16, 2009 - 12:59 AM
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Posted: May 16, 2009 - 05:13 AM
For gelcoat filling and buffing I have used 400 and 600 grit cloth. To get new gelcoat (filler type repairs) level with the original finish I sanded aggressively with the 400. Where the original finish it was level, I did a once over with the 400. It was also just a once over with the 600.
Where there is exposed glass I would seal that up with new gelcoat and remove as little original gelcoat as possible (unless the paint manufacturer says otherwise).
Rudy Can't Fail
edited by: kgatesman, May 16, 2009 - 04:25 AM -
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Posted: May 16, 2009 - 08:20 AM
Gel Coat is actually a non-stick application medium to keep the glass from sticking to the molds when a hull is laid. It doubles as a water tight coating to delay the intrusion of water into the glass.
If you trailer or store your boat out of water, you can actually do with a good primer.
Filling blisters with resin is putting the cart before the horse. Usually you end up with little resin filled bumps that call for a lot of sanding. Most blisters should be sanded to expose the inside of the blister for filling and then leveled off with a filler of resin and micro balloons. This opening up of the delaminated glass also allows the trapped moisture to dry up.
The result is a smooth and regular surface that when painted... looks great. I recommend Awgrip paint. Tougher than gel coat. Dedicated to a good result, time and patience, good intercoat sanding... at least three coats... and it will be a joy to see sail by.
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Posted: May 16, 2009 - 12:40 PM
I'd only sand down to the glass, and no further. It's better to have a bump than a weak spot imho.
Once you get the nonstick waxy layer off (what deepseas is talking about) gelcoat sticks to gelcoat very well. Once you've sanded off the top waxy layer, you're ready to apply.
However, if I remember my paints right, Interlux Brightside is a polyurethane. So, you need to make sure your primer will let you switch from a polyester or epoxy gelcoat to a polyurethane paint.
edited by: rhuntbach, May 16, 2009 - 11:48 AM -
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Posted: May 16, 2009 - 12:43 PM
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edited by: rhuntbach, May 16, 2009 - 11:45 AM
