Painting a Cracked Hull

Soda blast the gelcoat off. Then lightly fair, prime and paint. I sure as heck would not strip a layer of fiberglass off and re-fiberglass. Many of these posts have been fixed and have not gone through this extensive of a deal. You probably could get away with sanding good and high build primer.

Yes. This. Soda blast, fair, long board, high build, paint. Put the work into the hands of someone you can trust to take the proper steps or those cracks will reappear.

You need to remove the gelcoat. Fair and paint. Major job. Will keep cracking unless all removed

I dunno much about it, but I think the next step usually recommended after soda blasting would be (at least one) epoxy barrier coat layer.

Original post was from back in January, so maybe OBE by now...

-Chris

Sand/grind down to the first layer of fiberglass under the defective gel coat with 40 - 60 grit. Spray/cover exposed fiberglass with 545 epoxy primer, then spray 50/50 mix of ultra- build & high build primer filler within 35 hours or sand the 545 before the ultra-build / high build. Long board and short board in "X" pattern. Use a batten to mark high & low spots. Guide coat and long board - short board again till surface is fair using the batten method. Top coat.

I am finishing up a full sand/prime/paint on a 48 Cabo. Waterline to hardtop. I would ask the yard how many vessels with crazing they have done in the past. If not at least a dozen at this point I would consider finding a yard with more experience regarding this unique issue. Some areas like brow will require almost all gelcoat to be removed where as hull may only have moderate sanding necessary.

This is just speculation but I wonder if your yard knows the history of the cracking gelcoat. Known batches from a specific supplier that failed. Perhaps they are unaware of the history of the gelcoat issue and are concerned the cracking is the result of some failure in the glass? It's common practice to grind out crazing that is caused by flex, reglass, then fair/paint. Maybe this is their thought process and they don't know it's actually a failure of the gelcoat?

I have seen may cracked POSTS, I have seen the total removal of the gel coat and then painted and look great years after. I have seen the sand primer and paint systems. 3 of them up here in the NE and it doesn't work. The cracks come back because the gel coat and a little of the fiberglass still remains which is what continues to Crack. You need to make sure you know what your getting yourself into, who is doing the work and if they know what they are doing.
Your looking at 100 to 150k to repaint a 50. You don't want to see it crack again in 2 yrs.


If it was that easy post yachts would not have been bankrupt trying to repair the cracked boats.

Plenty of information out there online about Cook Composites & Polymers series 953 gelcoat that caused all of the troubles for Viking and Post from 1997 through 2004. Almost every last bit of this gelcoat has to come off as it just isn't prudent to take the chance and leave this 953 on the substrate even if it sands smooth to the touch and to the eye. It really doesn't matter if its light superficial crazing or deep cracking type of crazing as it will print through the 545, Ultra build and topcoat. There are paint contractors that specialized in the removal of this faulty gelcoat but the number of remaining vessels with this problem has dwindled significantly after 18 to 25 years. Most competent marine painting contractors with significant fairing experience can take care of this problem.

Looking at a 2005 Sabre Flybridge Sedan. Can anyone tell me if this Make, Model, and year was affected by the 953 gelcoat issue?