In this issue of the Composite 101, 202 and Advance Newsletter:

How to blast away a problem. :

I had a discussion with the new A/C technician at my home we discovered that we had in common a sailing passion. We discuss all sort of aspect of sailing and we touched the subject of fiberglass repair. He’s doing fiberglass repair on the side at the local marina, he seems to be quite known there for his expertise. He related a story that happen to him which scared the hell out of me!
I realized that even though he works with fiberglass, doing repairs, he knows nothing about the process of molding and making a part, that knowledge would have saved someone some serious money.
The owner of the boat bought, from a bank, after the bankruptcy of this former owner, this brand new sailboat. The man charged the part time fiberglass repair man him of applying an antifouling paint on the hull. Keep in mind that the boat never sailed, never went in the water freshly out of the factory.
So, the part time fiberglass repair man, applies the antifouling paint on the hull and realized that the paint when cured peeled off, it didn’t stick to the hull.
Now I taught that was interesting, because I know what happen, knowing how fiberglass part process work I knew what probably happened. But I probed the man to find what he did to solve the problem. He brought an expert to see the problem but not knowing how the process worked he miss interpreted the expert information and caused some major financial pain the boat owner!
The expert simply explains that at the factory, they used a mold release agent on the mold and that’s what cause the peeling. As we discuss in Composite 101, 202 and Advance the mold release agent in essential to the molding process. So, the repair man understood that the problem was that at the factory they used a mold release agent on the mold and ruined the gelcoat.
He came up with a blunt solution. He had the whole hull sandblasted to remove the gel coat. He was pretty proud of his work I didn’t want to challenge him either, I wanted my A/C to be properly repaired!
Here what he should have known. On every molding of a part a slight quantity of mold release agent comes off sticking on the new gel coat. Those who tried to stick anything even a masking tape on a new part know it’s almost impossible. The part has to be prepared if you want to fix something to it. Here’s 3 easy solutions.
1- Use soap and water. Simply use soapy water you can use dishwashing liquid. Then you can finish with Windex or any glass cleaner that should get rid of the problem.
2- The acetone. For the hard case you can use Acetone. This will for sure remove the wax.
3- The polisher. The ultimate way to remove any residue on the gel coat is to use a polishing compound and a polisher as polishing compound I suggest Aquabuff 2000.This is the proper way to get rid a wax problem Not sandblasting the gel coat!
You can perform a release test on the part to see if everything is alright. Simply follow the direction from the guide to perform the test.

Maybe all these peoples should have invest few bucks on Composite 101, 202 and Advance visual guide instead of blasting away a load of money…

Available at Guide.FiberglassTechnique.Com

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