Est. 1998 — 27 years of woodworking knowledge
Bubbles in epoxy - "Vacuum Degassing"?
Bob Matern
>The most recent American Woodturner showed some work by Jim Rinde using alot of epoxy. Epoxy, so I've been told, can have problems with small bubbles forming in it. But I'm told that a process called "vacuum degassing" can remove/minimize those bubbles.
Does anyone know how to go about degassing, say, a coffee cup full of epoxy?
Re: Bubbles in epoxy - "Vacuum Degassing"?
R.J. "Sam" Simpson
>Hi Y'all,
Bob, Epoxies are not as susceptible to this problem as acrylics. Careful delivery and mixing can eliminate most of it, and lowered viscosity by heating the resin will also help reduce the nuisance.
Pressurizing the liquids either in a vacuum or pressure chamber serves to reduce the size of the bubbles, to the point that they remain indistinguishable.
The best small scale system that I have seen available, is one that is sold as a kit for reproducing one off plastic tail lights for vintage automobiles. A search under collector cars and associated materials should find it.
Regards Sam Simpson.
Try breathing on the epoxy.
Dave Smith
>Hi Bob,
Carbon dioxide causes the bubbles to rise to the surface in epoxy. Exhaling on a lot of epoxy can cause a person to hyperventilate. DAMHIKT. Passing a flame over the surface will get the same results. You can use a propane torch. I use a candle lighter for small jobs. It is possible to catch the epoxy and/or wood on fire if you hold the flame too close for too long. DAMHIKT. Since I have obviously done a couple dumb things you may want to consider the source when evaluating my suggestion.
Dave Smith
Proving that nothing is sailor proof in Longview, WA.
Re: Bubbles in epoxy - "Vacuum Degassing"?
John Lucas
>We had a discussion on this on the AAW site the other day. You apply the epoxy to the turning and then put it in plastic bag and apply your vacuum pump. The vacuum pulls the bubbles out.
I've tried using my breathe and using a torch. Worked somewhat successfully on Mirror Coat epoxy but the other brands I tried were to thick it got rid of a few bubbles but not all.
I've use an 8x10 ziplock bag with one corner cut off to apply vacuum to a box that I veneered. I put the hose to the vacuum pump through the corner and taped it shut. I think this would work for the epoxy vacuum experiment. I hope to try it next week sometime.
What brand of Epoxy?
John Cahall, Ohio
>John, If you are going to fill large voids or use in combination with wood for turning what type/brand do you use? I've only used the "5 minute" stuff. Thanks.
Re: What brand of Epoxy?
John Lucas
>I'm still playing because I don't fill as much as I used to. I've started using better wood instead of trying to save every piece I get.
If I'm going to mix a powder in it to change the color I use whatever I have on hand. Usually the long set time. I'm not in a rush on these pieces and it's easier to mix everything together if your not rushed.
When I need clear I use System 3 mirror coat. It has a learning curve because it becomes very viscous while it's curing. It is extremely clear. Bubbles can be a problem so I've been reading all the posts on that with great interest.
I'm rapidly becoming a fan of system 3 and I think I'm going to spend the bucks to get a quart of each of the different types that Gougen Brothers sell. I've talked to a lot of wood workers who use it for boats and stuff and they all recommend that system.
Re: What brand of Epoxy?
Bob Matern
>Jim Rinde, who had that American Woodturner article, recommended a Jeffco Products 1403/4123 system for wood emersed in epoxy. Jeffco has a web site and distributors throughout the U.S.
I haven't tried it yet, just passing the info along.
Re: What brand of Epoxy?
Rick R, So Cal
>John,
Did you mean West System epoxy? That's the brand that the Gougeon brothers sell. System 3 is another excellent brand, but has nothing to do with West System.
Rick (who used to build wooden boats before discovering the lathe)