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Jan 30, 2013, 03:46 PM
Registered User

Light filler for glass

Need some recommendations for a lightweight filler to cover minor imperfections in glass.

I'm pretty good at glassing but occasionally end up with those small areas where I didn't wet sufficiently to completely fill the texture of the cloth. (Nope, I don't use a vacuum rig) I normally don't spot these until I have a coat of primer down. I've tried things like light spackling but cannot get it to hold in those minor imperfections.

Some ideas? The lighter the better.

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Jan 31, 2013, 08:06 AM
ARFs Are Me
TomCrump's Avatar
Many times, the use of automotive high build primer will do the trick. Just spray it on, and block sand the area.

If that doesn't do it, an automotive spot putty will fix you up. Prime the area, then apply the putty. After it dries block sand and then prime. The putty does shrink, so a few applications may be necessary.

I buy these products from a professional auto paint store. You should have something similar, in the UP.

Duplicolor high build primer. is available at almost any auto parts store, but I don't know if they would have spot putty.
Jan 31, 2013, 09:13 AM
Registered User

Thanks. I'll give that a try. I was just over at NAPA poking around the other day. I'm sure I'll find that Duplicolor product or something close. Always learn something new. (By the way, we do have color TV and dial phones up here now--big grin)

I'm an e-sailplaner almost exclusively but do stick build from time to time. Last stick build was a Pat Trittle short kit, the Pilatus Porter.

Think you've been getting much more snow than us. Our second year of a "snow drought" and that is depressing. Killing the snowmobile and sport shops. Got about 4-5 inches yesterday so looks like my wife and I can get out on the x-country trails. Not groomed of course.

Year before last, we came down to Harbor Springs and did the Little Traverse Wheelway. Overnighted in Charlevoix and headed back. Nice lazy ride and wonderful scenery.

Thanks again,

Jan 31, 2013, 10:22 AM
ARFs Are Me
TomCrump's Avatar
Hi Dave

Do you have iddoor plumbing ? LOL

We had 6'' the other day, and another 4" last night. Another 4" is expected by Friday. You can have mine. LOL

The high build primer isn't too heavy, but the spot putty may be heavier than you desire.

Good luck on your project.
Jan 31, 2013, 09:22 PM
Hope to get out of life alive
kenh3497's Avatar
A trick the DLG guys use is to slightly thin epoxy with alcohol and smear it on the offending spot. The thinned epoxy will soak through the unfilled weave and bond to the surface below and in your case fill the weave. In most cases, at least for me, the cloth is stretched tight enough when laying down the first coat of epoxy so it has not bubbled. I just didn't get enough epoxy in that spot. A second or God forbid a third application takes care of the problem.

Feb 01, 2013, 04:45 PM
Registered User
Micro balloons mixed with epoxy resin ? It doesn't come much lighter than that

Feb 05, 2013, 03:52 PM
Registered User
Thanks all...

I used the high build primer because the imperfections were so tiny. ( my wife says I'm too picky. Us RC guys "picky"?)

I've used the microballoons and epoxy in the past but that was in construction or to fill a void during repairs.

The technique I have not tried is the thinned epoxy. Think I'll experiment with that on some scraps.

Feb 06, 2013, 11:19 AM
Registered User
jhaywood's Avatar
they make a lightweight polyester glazing compound. Spot Lite by evercoat is one product. Squeegee on with a razor blade and then sand lightly to blend. It may take one or two applications unless you want to spread it heavier and block sand it all off including the surrounding primer...Its great since it cures in 10 minutes and sands easy
Feb 06, 2013, 05:09 PM
Registered User

Another new product for me. Thanks. Might be a good idea for some experimentation.


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