# Need advice on avoiding air trapping under glass



## jasonrl23 (Jul 27, 2009)

Any advice on avoiding random air bubbles that form 10 or 20 minutes after laying glass on bare wood?

My plan is to use West Systems special clear hardener, a single layer of 4 ounce glass, then one or two fill coats. Final finish will be UV stable Varnish. The bottom is going to be painted.


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## Guest (Mar 21, 2020)

Jason, do your glassing in the afternoon to help with the off-gassing of the wood. Basically, you want the wood warm and cooling when you glass if that makes sense? I signed back in just to answer, I’m social media distancing for a while lol!


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## BrownDog (Jun 22, 2019)

Instead of an air bubble could it be a dry spot where the wood is soaking your resin in leaving the cloth dryer with a poor bond?


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## DuckNut (Apr 3, 2009)

You need to coat the wood with resin and let it kick or even dry before laying the glass.

Brown dog is right. The wood is soaking up the resin and coating before you will seal the wood.


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## Sethsawyer (Apr 5, 2019)

WArm the shop temp. 80ish then cool as you are laying down epoxy cooling causes the bubbles/ epoxy to get sucked into the wood due. Rising temps cause gas expansions and bubbles in the epoxy/ not a clear finish.


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## jasonrl23 (Jul 27, 2009)

Boatbrains said:


> Jason, do your glassing in the afternoon to help with the off-gassing of the wood. Basically, you want the wood warm and cooling when you glass if that makes sense? I signed back in just to answer, I’m social media distancing for a while lol!


You are awesome man. My board will be laid up in doors. So I can control the AC. Totally understand what youre saying.


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## jasonrl23 (Jul 27, 2009)

BrownDog said:


> Instead of an air bubble could it be a dry spot where the wood is soaking your resin in leaving the cloth dryer with a poor bond?


Between you, Boat, Seth, and Duck, I think Ive got a solid plan.


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## Capnredfish (Feb 1, 2012)

Here you go.
https://www.fgci.com/item/123757/Used-to-release-air-trapped-near-the-surface-of-Table-Top-Epoxies-/


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## Guest (Mar 22, 2020)

Capnredfish said:


> Here you go.
> https://www.fgci.com/item/123757/Used-to-release-air-trapped-near-the-surface-of-Table-Top-Epoxies-/


This product is for releasing air bubbles on the surface of a poured in place epoxy. Not the same as the problem he is having. He had one or several things taking placed that have already been addressed. Good product for what it’s designed for though! A torch or high temp heat gun will usually do the trick in this case though.


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## GaG8tor (Jul 8, 2019)

Watchya building? Looks cool


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## Capnredfish (Feb 1, 2012)

Boatbrains said:


> This product is for releasing air bubbles on the surface of a poured in place epoxy. Not the same as the problem he is having. He had one or several things taking placed that have already been addressed. Good product for what it’s designed for though! A torch or high temp heat gun will usually do the trick in this case though.


Darn it Boat. I tried. Hit it with a lighter after applying then. The heat should do the trick. I did miss the table top part. I looked it up quick because I had heard of it in the past.


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## jasonrl23 (Jul 27, 2009)

GaG8tor said:


> Watchya building? Looks cool


It’s a 14’ paddle board. Okume hull covered in 6oz plain weave. Sitka Spruce and Mahogany deck.

Pic is before any glassing was done. Kind of how I want it to look. Hull will be painted Flag Blue.


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## jasonrl23 (Jul 27, 2009)

Boatbrains said:


> This product is for releasing air bubbles on the surface of a poured in place epoxy. Not the same as the problem he is having. He had one or several things taking placed that have already been addressed. Good product for what it’s designed for though! A torch or high temp heat gun will usually do the trick in this case though.


I’ve used that stuff before. Works really well for table top jobs. Heat gun is the way to go. You can push epoxy around and pop bubbles at the same time.


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## GaG8tor (Jul 8, 2019)

Is there a plan for that? Or did you design this?


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## jasonrl23 (Jul 27, 2009)

GaG8tor said:


> Is there a plan for that? Or did you design this?


It’s the Koholo 14 from CLC Boatworks. Only changes to their plans I made was the stripped deck, and decided to paint the hull because the scarf joint is ugly imo.


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## Guest (Mar 22, 2020)

Capnredfish said:


> Darn it Boat. I tried. Hit it with a lighter after applying then. The heat should do the trick. I did miss the table top part. I looked it up quick because I had heard of it in the past.


 I’ll log back out now


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## jasonrl23 (Jul 27, 2009)

DuckNut said:


> You need to coat the wood with resin and let it kick or even dry before laying the glass.
> 
> Brown dog is right. The wood is soaking up the resin and coating before you will seal the wood.


Ended up doing this and it’s great advice. The mahogany was slow on the uptake and keeps producing micro bubbles. The spruce absorbed it like a sponge with no bubbles.

You can see it pretty clear in the front view pic


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## DuckNut (Apr 3, 2009)

jasonrl23 said:


> Ended up doing this and it’s great advice. The mahogany was slow on the uptake and keeps producing micro bubbles. The spruce absorbed it like a sponge with no bubbles.
> 
> You can see it pretty clear in the front view pic
> View attachment 128604
> View attachment 128606


If you are still getting the tiny bubbles let it cure for a day and coat it again and let it dry for a day and then wet and lay your glass. That should seal the wood and prevent the off gassing.


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## jasonrl23 (Jul 27, 2009)

DuckNut said:


> If you are still getting the tiny bubbles let it cure for a day and coat it again and let it dry for a day and then wet and lay your glass. That should seal the wood and prevent the off gassing.


Thanks! Will do. Only have about a quart left but I think I have enough to do both. Glue Products closed so Im kind of stuck with their brand of epoxy for now. Have to layup 5 yards of 4 oz then 1 fill coat. Varnish after.


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## Gatorgrizz27 (Apr 4, 2015)

I didn’t have any issues with wetting out the glass by using a Bondo spreader. You can really force it through the weave and then squeeze out the excess.


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## DuckNut (Apr 3, 2009)

Gatorgrizz27 said:


> I didn’t have any issues with wetting out the glass by using a Bondo spreader. You can really force it through the weave and then squeeze out the excess.


His issue is the wood was soaking up the resin and pulling it out of the cloth and causing dry glass.


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## JC Designs (Apr 5, 2020)

DuckNut said:


> His issue is the wood was soaking up the resin and pulling it out of the cloth and causing dry glass.


That and the wood off gassing with temperature.


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## jasonrl23 (Jul 27, 2009)

JC Designs said:


> That and the wood off gassing with temperature.


Thankfully it’s under central air. That room is around 78 to 80 during the day and never more than 50% relative humidity. Good advice as always though.


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