# Pressure pot vs vacuum pot; why one over the other?



## P89DC (Oct 1, 2017)

I want to stabilize various wood pieces for knife and saw handles. I was ready to jump into it with a vacuum pump and chamber/pot. Then I saw some epoxy casting that used a pressure pot at ~50psi.

Can someone help me understand when to use one technique over the other?


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## RichBolduc (Jan 30, 2018)

Vacuum chamber is for stabilizing wood. It sucks all of the air out of it and draws in the resin. Once the chamber stops pulling bubbles, you let the wood soak in the chamber and the resin for at least 2x-3x the amount of time it took for the bubbles to go away.

A pressure pot is for casting. What happens here is the pressure compresses the bubbles and makes the smaller than you can notice. You do not want to cast in a vacuum chamber as a lot of casting resins will start to cure before you can get the bubbles out resulting in a foaming mess.

If you want more info on stabilizing, I suggest checking out www.turntex.com as Curtis over there is pretty much the stabilizing guru and has videos along with selling the best stabilizing resin and some say the best stabilizing chambers also.

Rich


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## P89DC (Oct 1, 2017)

Pressure pot for casting, ok, got it. Thanks!


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## P89DC (Oct 1, 2017)

Do other finishes besides epoxy work in a vacuum chamber? I wanted to infuse poly into tight grained wood handles such as pizza cutters and chisels.


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## splintergroup (Jan 20, 2015)

> Do other finishes besides epoxy work in a vacuum chamber? I wanted to infuse poly into tight grained wood handles such as pizza cutters and chisels.
> 
> - Eric


 I've done vacuum tests with my vacuum bag with mineral oil for cutting boards (works excellent) and poly for other items. It does work, but you really need to thin it out (50%) so it can flow.
This was tested on red oak which has relatively huge pores so a denser wood probably would take much longer (I went 6 hours with 20" of vacuum at 4600 feet altitude).

It will take a long time to fully dry internally. I tried curing at low temp in a dehydrator oven at 130 degrees, but the outgassing of the solvents forced much of the poly back out.


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## bigJohninvegas (May 25, 2014)

Check out Zac at nvwoodworks. Or google Zac Higgins stabilizing wood.
You will get a three or four part you tube video.
He did a demo for my local woodworking club a few years back. 
During his demo, I learned how to use a Harbor freight pressure pot for both vacuum and pressure.
With stabilizing its just the vacuum, followed by some oven time.
With casting you do both, A timed vacuum to de gas, followed by pressure. 
I have got that harbor freight set up ready to go. But I have not had time to use it yet. 
So thats all I got. But Zac's web site and you tube channel are full of info. 
Also a Scott grove demo I attended at AWFS back in 2017. he was resin casting, not stabilizing. 
He used a preassure pot as a vacuum chamber. He had an over sized clear acrylic disk, with a foam gasket that he used as a lid in place of the pressure pots lid. He was able to watch the resin or wood degas. (Same as stabilizing), then switched to the pressure pot lid. 
So one tool, two jobs, bang for the buck.

https://nvwoodwerks.com/

good luck,


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