How much GelCoat??

[EBEACH]

Don,

I recall a post of yours a number of years ago regarding this. If I recall, you were adding about 15% patch booster? What type of gun do you use, and how much working time do you have with whatever ratio you use?

I sprayed a small about of 50/50 duratec last night with mixed results. It started out ok, but then some small dimples showed up in a few areas. I checked for water in the line, but that was not the case. I had just sanded the panels and cleaned with acetone before the application, and the acetone had time to flash off before spraying.

With only an 8oz batch and 5cc’s MEKP, the last bit started to kick in the gun. Not a fun time with the HVLP gun (2.3mm tip). This method does create a fair amount of overspray mist, but laid out really smooth.

I’m thinking that a slightly thicker mix (less duratec) in a dump gun and a number 3 or 4 tip might be the way to go? I wonder if using less duratec would still allow for a full cure?

Thanks, Jim

[hermco]

25% booster to gelcoat ratio. I would not use the Duratec if you can avoid it. 1.5% catalyst is 4cc for 8oz.
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[EBEACH]

Don,

Thanks for the info. Too bad I just bought the Duratec. I was aware of the patch booster from Ferro. I’m using Ferro brand gel coat, but the working time as indicated on their website says 5 minutes with the patch booster.

I used 2% MEKP as directed by most manufactures. I’ll go down to 1.5%

What are you using to spray with and tip size? What are your working temps and are you cooling the material prior to use, or is it at room temp?

Thanks, Jim

[hermco]

I did the bottom of my boat with gel at room temp with booster and a cheap 2 gal pressure pot from Harbor Freight. Mixed the gel in gallon milk jugs with the tops cut off. 3 coats of gel. Then spent the next two days wet sanding and buffing. Came out nice but is very labor intensive. I'm glad I wasn't paying myself by the hour!