Building a Mold and Laminating Schedule

[Cpt Albert]

Hello,
I would like to get some information on building a mold for a 17’ x 5’ fishing boat. I just about have the plug ready to make the mold. My questions are:
1- What laminating schedule should I use to build-up the mold?
2- What type of tooling gel coat is best?
3- Should I have a steel frame around the mold and if so how thick should the material be?

I appreciate any help that I can get.
Thanks..
Cpt. Albert

[Eagle Boats]

Capt.,

The laminating schedule I use when making a mold is mat, mat and more mat. I start with tooling gel coat, and then use a skin coat of 3/4 ounce mat. Let that cure and go over every square inch of the cured skin to make sure that there are no air bubbles. Then scuff up the skin and start applying 1 1/2 ounce mat. I typically do not add more than two layers of mat per day. I tend to be overcautious and am concerned about exotherm buildup. I build up the fiberglass to about 1/2 inch thick. It may be overkill, but then again, I tend to overbuild. In regards to a frame, I use black plumbers pipe, 1 1/4 inch inside diameter and I create a framework to fit over the mold. Once the framework is welded it is then glassed to the mold. However, no part of the steel framework touches the mold, as I do not want to create any hardspots on the mold.

I am not sure what you mean regarding the type of tooling gel coat. In terms of manufacturers, I was using Cooks. I also used Cooks tooling resin for the layup.

[Russ]

Eagle is right on.
I always stand the frame off of the mold about4 inches and then don't build up the tabbing too thick. Wrap the fiberglas around the tube then bring it together to form a single web at the mold.
The surface of the mold is key to being long lasting. Bear in mind that at some time after making many boats you may have to sand and buff it out. That will be the result of heat buildup from each boat made. Even though mat sucks as a good laminate it is less inclined to show print through as a result of resin shrinking and the fibers not shrinking.
Nowdays I build a bit different since I vacuum at least the first 1/4 inch of mold surface. I can better control the possibility of high resin content and the subsiquent resin shrinkage. (food for thought)

[bluethunder12]

only thing i would add to the glass part is a layer of cloth i like that x-tra strenght , and as far Tooling i use the same Cooks all the way cooks also makes a book that tells you the procedure from the spray to the glass i call it the fiberglass bible.

[SamSam]

Originally Posted by bluethunder12

only thing i would add to the glass part is a layer of cloth i like that x-tra strenght , and as far Tooling i use the same Cooks all the way cooks also makes a book that tells you the procedure from the spray to the glass i call it the fiberglass bible.

Cooks? Who and where are they? Sam

[Russ]

Cooks is in Kansas City Mo.the real name is CCP, Cook composites & polymers.
Years ago they were Cook paint & varnish.
Telephone is 816-391-6000

[ondarvr]

Thanks guys, It's nice to here good things about the company I work for and the products I sell.
There is a new book and CD out, with even more information on what to do, and what not to do, but it's hard to come by right now, the first printings have all been given out as soon as the ink dries.
So far the advice given to Cpt Albert is very good, CA I'm sure you'll have more questions and it looks like these guys give good answers.