gary7
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I glassed a rocket and was left with heavy weave. I tried filler primer but the weave remains even after about five coats of the primer. What can I use now to fill the weave that will adhere to the primer?
FG Weave Filler over a Primer?
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SRBell
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I would sand the top of the weave to expose the top of the glass, but don't grind it down any further. The mix up some laminating epoxy (I presume you used epoxy, if not substitute for poly resin) and mix in light weight filler like micro balloons. Use something like playing card to take off the excess. Sand and prime, smooth as glass... Well, plate glass that is : )
Pat_B
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I'd use an automotive filler. There are a number of products known as "icing" that are two-part lightweight fillers that are easy to sand. Of course they smell reallyi bad and need to be used outside, but anyone doing any fiberglass work on autos would be using that product.
see https://www.autobodytoolmart.com/usc-icing-polyester-finishing-putty-p-10969.aspx
see https://www.autobodytoolmart.com/usc-icing-polyester-finishing-putty-p-10969.aspx
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The above has worked well for me. I used Phenolic Microballoons as the filler for the epoxy. I mixed it to a consistency where it spread easy, but wouldn't drip off. Once dry, it sanded very easily and quickly filled the weave of the fiberglass.
-- Roger
SRBell
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Very good point, don't sand into the weave. I usually wet the glass just enough to wet it down to its mating surface. Then after it's kicked a bit, I fill the weave with more resin using a playing card. If that seems too heavy, you probably need lighter glass in the first place lol.
mr_matt_II
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https://www.polyfiber.com/epoxy/
Very light and sands beautifully.
Alternative is the epoxy with mico added or a much higher build promer design for what you are tring to do.
test for compatability first, you have to make sure whatever you put down will dry over that primer you already applied
Very light and sands beautifully.
Alternative is the epoxy with mico added or a much higher build promer design for what you are tring to do.
test for compatability first, you have to make sure whatever you put down will dry over that primer you already applied
degreaser
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These microballoons work well mixed with laminating epoxy. I've been using a 50/50 mix by weight. https://www.westmarine.com/webapp/wcs/stores/servlet/ProductDisplay?productId=38889&catalogId=10001&langId=-1&storeId=11151&storeNum=10104&subdeptNum=10296&classNum=10299
Do you sand between primer coats? Filler primer will eventually do the job, but it might take a lot of passes.
I wouldn't worry about the weave. The rocket will look great on the pad.
But that's just me.
--Lance.
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