gel coat both sides...

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#1

hi everyone,
i’m planing a project and would like to ask a few questions.

  1. how do you get a perfectly smooth gel coat on both sides of your form
  2. whats the best way to get a hard gell coat with NO pinholes to prevent mold growth?
  3. any suggestions for this project…

project: i am going to build a chamber about 6’x4’x9 inches. the chamber will have a slight curve to it and no corners, all the edges will be rounded. one of the large sides of the chamer will be a detachable panel. i would like the inside of the chamber to have a smooth gelcoat and be mold proof. i also want the outside of the chamber to be smooth, but this is not the critical side.

i’ll fabricate the chamber and the door as two different pieces. so far it seems that i need to make a two part female mold for the chamber because a plug or male mold will get trapped inside the casting ( the panel will not take up the whole side).

by using a female mold, the ouside of my form will have a gel coat on it. and i’ll have to brush a resin/gelcoat on the inside, but this will leave streaks won’t it?

thanks for any tips you have,
max

#2

Kind of hard to follow without pictures or drawings…but you will get a smooth Gel coat surface off a mold that is smooth, but it is best to spray and not brush the gel coat as then it is not even. You will leave areas for air to be trapped.

If after gel coating, laying up a part and you want to gel coat the lback laminated side, it won’t be smooth unless you do a lot of sanding and polishing! Even so, then add some Surfacing agent (liquid wax) to that gel coat to seal off the air and then you will be able to sand and polish it easier & better.

If you were to go to Vacuum Infusing Process, both sides will be smooth but you will need to repaint it if you don’t want to see the lamination.

#3

Another approach if you are up to the task is to make an outer and inner mold. Using vacuum infusion and an interlaminar flow media in a closed mold process, you could infuse the whole piece at once and have a finished surface on both sides. I am be missing the objective here, but you would them have seams on the joining pieces, yes?

#4

If you have some pictures or drawings, post them up, that will give us an idea of what your goal is and what the best solution would be.