Posted: 14 January 2007 at 4:50am | IP Logged

There is no need to remove old gelcoat unless of course it is damaged.

If damaged (scratched, chipped, delaminated) then of course you have to repair it with a good resin based filler.

You'll only get a good smooth painted-over surface if the underground is also smooth.

You also need to degrease it thoroughly. First with a detergent to remove bio-surface, then with something like acetone (not harmfull) or trichloreE (harmfull for your skin)

Jan

Posted: 15 January 2007 at 2:00am | IP Logged

Maybe I don't know what 'crazed' gelcoat means???

Is it cracked gelcoat?

Jan

Posted: 31 January 2007 at 8:10am | IP Logged

for stress cracks, use dremel and open up all the cracks then fill with fairing compound.  recommend Awl-fairing, good epoxy based fairing compound. 

 Your paint job is only as good as the prep job so hit the surface with a DA(dual action sander) use 100g to knock it down. prime the surface then sand with 220g then  top coat. 

Dewalt makes a very good quality DA, homedepot price about 75.00.  get plenty of sanding disks as you will use many.  of course if you have access to high volume air compressor then use an Pneumatic DA

Posted: 01 November 2009 at 2:31pm | IP Logged

Some very interesting replies to Snowgoose.  I have a 1986 Sea Ray 410 aft cabin. The deck area above the aft cabin has lots of small spider web type carcks in the gelcoat refered to crazing.  I am also considering painting over this surface, as trying to re gelcoat is way to expensive and time consuming.  I also have several screw holes in this area due to old carpet snaps that need to be filled.  I was just going to use Marine Tech to fill the holes and sand them smooth before painting over them.  I was also planning on extending the painting to include the walkways to the bow of the boat.  The reason for this is that they are very slippery so I'm hoping to find a paint that I can mix in some sort of abrasive allowing me to select the amount of abbrsiveness needed in various areas. The abrasive I'm hoping will also hold the new carpeting in place so I can avoid putting in new snaps.  All these areas to paint are already outlined for me as Sea Ray textured these areas in the gelcoat.  A poor attempt to not make it so slippery.  Anyway, I was planning on taping these areas off and just using a roller to apply the paint.  It was interesting to note that Mike M2 stated the only prep was to degreese and make sure the area to be painted was very clean, where as 67Hat34c recommended sanding the area to be painted, I'm assuming to both clean it up and rough it up a bit for better paint adhesion. I thought the high speed sander recommended was a bit aggresive and could put circular gouges in the surface if your not extremly careful.   I would probably use a palm sander with its flat surface and just run it lightly over the gelcoat.  I'm also assuming that after sanding you would still want to wipe the area clean with something like acetone or paint thinner. Sanding would obviously take more time, and my storage facitlity doesn't like sanding, but I can get around that if I must.  I see these kind of surfaces on sail boat walkways, what type of paint and abrasive do they use?  Can you add abrasive to Trilux by Interlux? I'm also hoping that the painted surfaces will hold up for many years, not someting I would want to do every couple years.  I'm also assuming that the paint will waterproof the back deck area to keep the water out of those little cracks.

Any comments on the above procedures and products would sure be helpful. I'd like to get this job taken care of this winter.  My boat is stored on lake Michigan and is slipped at Ellenwood landing on White Lake.  She is named Shangri La.

Thanks,

3rd Ray 

Posted: 11 November 2009 at 9:47pm | IP Logged

Hi 3rd Ray:

We just completed a major deck restoration on our 1983 Endeavor 40 Ketch.  There was crazing everywhere.  We were told, and faithfully followed the advice, to drill out each crazing line with a dremel tool leaving a "V" shaped groove that we then filled with epoxy (We used West with a medium density filler).  The drilling and subsequent sanding proved to be a major job.  As we progressed we learned that using the new Epoxy "G-flex" product with the West 406 fairing compound filler proved to make the sanding easier and, we believe, the subsequent finish less susceptible to re-crazing (a good portion of our crazing is in areas taking a load from sail bearing jib stay).  For a finish we first applied an Interlux two part Epoxy primer, then a one part Toplac (Interlux) finish on cabin sides and deck waterways with a two part Perfection (Interlux) on all the non skid areas (using the sand product between coats).  Shortly after finishing the entire deck, masts were stepped, rigging was tightened down and crazing reappeared in a couple of spots, even through the relatively high build two part primer.  At least this is down to a very few spots which, with the experienced gleaned, will be easily manageable.

Chuck Graham

Posted: 15 November 2009 at 10:39am | IP Logged

Chuck,

Thanks for the reply, I've copied your message and will be investigating the products, and techniques you have suggested.

Mike (3rd Ray)