Stains in gel coat
- Thread starter Stampe
- Start date
Ron Ketcham
Active member
Look at it with a 30x lighted magnifer before you do anything else. See if the gel is "porus", or in other words, does not look like the surrounding area.
Then, I "may" be able to help you.
Let me know.
Then, I "may" be able to help you.
Let me know.
Ron Ketcham
Active member
Very poor gel coat repair. Doesn't appear that even wet sanding is going to fix that. Most likely will require the poor repair ground out and re-patched. You can even see the fiber glas matt showing through in parts.
Well the thing is it aren't a repair, what I can see..
It seems like something have corroded into the gel coat, and that was what I told the owner. It is over more areas aswell so most likely they have been using to aggressive cleaning products when maintaining the boat, or they applyed it in the direct sun wich made it corrode into the gel coat.
It was a great tip with the microscope! Thanks a lot Ron
It seems like something have corroded into the gel coat, and that was what I told the owner. It is over more areas aswell so most likely they have been using to aggressive cleaning products when maintaining the boat, or they applyed it in the direct sun wich made it corrode into the gel coat.
It was a great tip with the microscope! Thanks a lot Ron
Ron Ketcham
Active member
Then it is a manufacturing defect. For any solvent or corrosive to "eat" in to the gel coat would take a very highly evaporative solvent with some styrene in it, held there for hours on end.
Have you any knowledge on how a fiber glas hull or other parts are made?
What mostly likely happened is that the applicator ran out of gelcoat (must apply 18 to 20 mil wet to the mold) when applying it to the tooling mold. Changed out and went on, then follows the chopper gun with resin in it. If the defect runs in a seam like appearance, that's probably what happened. Am pretty sure this is a manufacturing defect that just took a little time for the very small amount of gel to lose it's ability to hold
In less words, there is not enough gelcoat in the affected area and to sand it will just make it worse.
Have you any knowledge on how a fiber glas hull or other parts are made?
What mostly likely happened is that the applicator ran out of gelcoat (must apply 18 to 20 mil wet to the mold) when applying it to the tooling mold. Changed out and went on, then follows the chopper gun with resin in it. If the defect runs in a seam like appearance, that's probably what happened. Am pretty sure this is a manufacturing defect that just took a little time for the very small amount of gel to lose it's ability to hold
In less words, there is not enough gelcoat in the affected area and to sand it will just make it worse.
Ok, I wont sand it, but there is more on the boat as well. And it feels weird if it comes from the factory because it is a pretty large boat. But It can perhaps breakdown over time?
Well I have no other clue about boats and how they are made, but this is good information! Thanks Ron
Well I have no other clue about boats and how they are made, but this is good information! Thanks Ron
Ron Ketcham
Active member
What brand of boat, what country was it manufacturered in? What year was it built? It just looks to much like not enough gelcoat into the tooling mold, which I gave you the recognized specs on.
lobster poutine
New member
if you can match the gel, (which will lkely be tough) it is repairable.
When i worked in a major yacht manufacturer, we used to grind out a bit of gel and expose a depression that we would fill. we would use use a powder filler (ill try and find the name)...and we would mix it with the gelcoat and it made it a bit thicker...like a paste.
we would then spoon it in with a small putty knife (into the depression we ground out), and then covered it with a piece of rigid plastic....for the life of me i cant recall the name of the plastic, but it is super shiney (therefore very slick) clear plastic and we placed a small square of it over the repair.
once the gel/powder mixture dried, we were able to peel the plastic off, and there wsa a very nice smooth repair that we could wetsand and buff out.
we always used aquabuff 1000 and 2000
When i worked in a major yacht manufacturer, we used to grind out a bit of gel and expose a depression that we would fill. we would use use a powder filler (ill try and find the name)...and we would mix it with the gelcoat and it made it a bit thicker...like a paste.
we would then spoon it in with a small putty knife (into the depression we ground out), and then covered it with a piece of rigid plastic....for the life of me i cant recall the name of the plastic, but it is super shiney (therefore very slick) clear plastic and we placed a small square of it over the repair.
once the gel/powder mixture dried, we were able to peel the plastic off, and there wsa a very nice smooth repair that we could wetsand and buff out.
we always used aquabuff 1000 and 2000
Ron Ketcham
Active member
FiberGlas Evercoat sells gel coat, gel coat putty, seperate color toners, etc. I was using some yesterday on an old SeaRay.
No need for a special plastic, any plastic freezer bag will do it, just cut to size and tape down.
If you have a large area, then use a thin, flexable plastic cutting board like Aldi sells once in a while. Great for large area repairs.
The resin in the product is anti-aerobric so shutting off air supply kicks it over.
No need for a special plastic, any plastic freezer bag will do it, just cut to size and tape down.
If you have a large area, then use a thin, flexable plastic cutting board like Aldi sells once in a while. Great for large area repairs.
The resin in the product is anti-aerobric so shutting off air supply kicks it over.
lobster poutine
New member
Lexan was the name i was thinking of...
i never tried it with a plastic baggie, but the lexan was nice becasue it left a real nice finish (its semi rigid and super shiney) so it is a real treat to work with.
its not expensive either.
i never tried it with a plastic baggie, but the lexan was nice becasue it left a real nice finish (its semi rigid and super shiney) so it is a real treat to work with.
its not expensive either.
