Vacuum stabilization...doesn't compute (PIC)

[Dario]

Okay as promised to Billy, I finished my vacuum set up and started using my vacuum. It works wonderfully, wood starts bubbling in the solution the instant I turn the vacuum on. What doens't compute is...seems like the air in the wood never runs out!!! I did several cycles releasing vacuum after each cycle and air still comes out like crazy on all of them!!!

One time, I let the vacuum run about 15 minutes...amount of bubbles coming out of the blanks seems never ending!!! [:0][B)] BTW, I am doing redwood burl blanks.

Below is my cheap setup...less than $28.00 incluidng a Gast vacuum $10.00, tubes, gate valve and fittings $17.00 (excludes blanks and solution ). Bubbles finally subside a bit on this last run...there is hope still LOL.

 

[smoky10]

Dario, I had to use the shut off valve to regulate the amount of vacuum going to the jar or it would boil the liquid out of the jar. I had to regulate it down to just a little getting through and then it worked better. As you know regulating the volum will not effect the amount of vacuum, just take a bit longer.

 

[Dario]

Tom,

Same here, I regulated using the ball valve []. If I didn't regulate, the bubbles/solution will get sucked out! The first run I had to close the valve before powering the vacuum because the bubbles reach the top of the jug in about a second!

 

[alamocdc]

Dario, I've had blanks bubble for two days. Of course the bubbling eventually subsides when I close the valve and just let them sit under the vacuum, but when I release and go again back come the bubbles. And yes, even with redwood and redwood burl.[]

 

[woodbutcher]

Some of the bubbling is probably moisture. I suspect the air is gone after 30 min or so. Take a piece of air dried wood and place it in your chamber under a full vacum, you will notice dark areas form on the wood. I suspect that is moisture being pulled from the wood. In a vacum moisture boils and hence the bubbles. Just a theory but I feel it holds water..or air.......or somthin[]
Jim

 

[Mudder]

Dario;

Your bubbling is normal. Redwood (or at least the redwood that I have used) is not a very dense wood and it might bubble for days. Another thing is that you appear to have a lot of blanks in that jar (not a bad thing) and that adds to what you see. I usually draw a vacuum for an hour at a time, releasing it for a minute to two until bedtime and I leave it under vacuum overnight and begin again in the morning. When the blanks become saturated they should sink in the solution but they still may release air bubbles. My cahmber is a bit different so I also remove the top occasionally and "stir" the blanks so that air is not trapped between them. Keep going, looks to me that your doing fine.

 

[Cowboy]

Dario:

What is the solution that you are soaking them in? See my other post, I did not seem to have too much luck with the redwood.

Chris

 

[Dario]

Chris,

My solution is plexi-acetone mix (plexiglass dissolved in acetone). The solution turned red fast! I will experiment using the same solution on some spalted wood and see if I can get it penetrate deep and how the color affect the blanks [].

I am also planning on trying Minwax quick drying poly and see how that works. That will have to wait though since this solution seems to work just fine.

Another thing I noticed is the bottle/jug got cold fast! The bottle starts condesating water outside in less than 3 minute (just an estimate).

 

[Blind_Squirrel]

Originally posted by woodbutcher
<br />Some of the bubbling is probably moisture. I suspect the air is gone after 30 min or so. Take a piece of air dried wood and place it in your chamber under a full vacum, you will notice dark areas form on the wood. I suspect that is moisture being pulled from the wood. In a vacum moisture boils and hence the bubbles. Just a theory but I feel it holds water..or air.......or somthin[]
Jim

So, in theory, you could use a vacuum to dry blanks faster...

 

[smoky10]

I like the plexi-acetone mix for stabilizing burls and spalted wood. I used it on some "blue spalted buckeye burl" I got from someone, can't remember who though. []

 

[Dario]

Originally posted by smoky10
<br />I like the plexi-acetone mix for stabilizing burls and spalted wood. I used it on some "blue spalted buckeye burl" I got from someone, can't remember who though. []

I did stabilize a few buckeye burls too...now I think my love for this burl came back []

 

[Dario]

Originally posted by Blind_Squirrel
<br />

Originally posted by woodbutcher
<br />Some of the bubbling is probably moisture. I suspect the air is gone after 30 min or so. Take a piece of air dried wood and place it in your chamber under a full vacum, you will notice dark areas form on the wood. I suspect that is moisture being pulled from the wood. In a vacum moisture boils and hence the bubbles. Just a theory but I feel it holds water..or air.......or somthin[]
Jim

So, in theory, you could use a vacuum to dry blanks faster...

There was a post about drying blanks using a vacuum...and it supposedly should work well. Do a search...it is very educational. I did make a fool out of myself on that thread so I won't post the link here [}] LOL

 

[moose]

Has anybody posted their "recipes"? Amount of plexiglass to acetone?
Other stabilization material ratios appreciated also. []

Are you just buying a new sheet and cutting it up?

thanks,

moose

 

[moose]

Another question,

Has anybody done a plexi treatment on anter?

moose

 

[Dario]

Moose,

I am currently using an old piece of plexi that I got from a garage sale (for free). No recipe for me just dissolve as much as I can on a separate bottle then I pour it to the vacuum chamber/jug as needed. I dissolve it further if it gets too thick.

My initial was approximately 25" x 11" x 1/8" plexi to a gallon of acetone. It did take a few days to totally dissolve everything and I have to shake the bottle every now and then to mix it up ...seems to help accelerate the process a bit.

 

[smoky10]

You can get the acetone from Home Depot, Lowes, or about any hardware or home supply store.

 

[RussFairfield]

Dario,
Think about this for a minute. You want to fill ALL the the void in the wood with the stabilizer. The bubbles are a sign that that is what is happening. As long as there are bubbles, there is still air in the wood, and the wood isn't filled until the bubbles stop. That is what should be happening. If you did stop before it quit bubbling you would only have a partial filling of the wood, and would find air pockets and voids in the stabilizer as you turned it away.

Some wood is easier to stabilize than others. Redwood is a very open wood that doesn't give up its air easily, and there is a lot of it. Plan on at least 24-hours under vacuum.

It would be a good idea to add a bleed valve and a vacuum gauge to the suction line. A ball valve will work, but a needle type valve would give better control. A pinch clamp on a short piece of hose works with the volumes you are using. That way you could adjust the vacuum, and start with a lower vacuum and reduce the initial foaming. Then gradually close the bleed valve over time and increase the vacuum.

For a simple process, it is best that the wood be bone dry, and that means NO moistuire in the wood. Moisture in the wood can be a mixed blessing for stabilization because it has to be sucked out of the wood along with the air. That means it has to be turned into a vapor (steam), and that means the solution in the pot has to be heated, probably to about 155F for practical purposes. It will also speed up the penetration. However, working with hot Acetone adds a safety issue that you don't want to have.

Using a vacuum makes wood dry faster because the lower pressure makes the water in the wood evaporate, and water vapor moves through the wood faster than liquid water. It also alows you to take the wood to a lower moisture content that allowing normal evaporation in free air. If your wood is already air dry, there is nothing wrong with putting the wood in the vacuum for 24-hours before adding the stabilizing solution. At the worst, it would accomplish nothing, but at the best, it will get the wood closer to the bone dry condition for stabilizing. Overnight in the oven set at 120F will do the same thing to a pen blank and it works for me.

 

[Dario]

Russ,

Thank you. I know the concept but what eludes me is the amount of bubbles created. I can't believe there is that much air inside a small blank and I am already witnessing it! I know too that at that time the air bubbles are already expanded due to the vacuum but still it is just unbelievable. Note I was just watching one blank in particular and it just keeps on bubbling like crazy!!! LOL

All the assurance that it is normal helps though.

Now I need to add a hose and pipe out of the garage the exhaust of the vacuum. Acetone cannot be good for my health [xx(][B)].

Thank you!

 

[pssherman]

Dario,
How much vacuum are you pulling? The vacuum pump that you are using looks like it could pull a deep vacuum. If it is pulling a deep vacuum then you are very likey evaporating the water still in the blank. The resulting water vapor will form bubbles just like air does. If the bubbles stop shortly after closing the valve and then restart when the valve is opened and the vacuum pump is on, then the bubbles are from water vapor not air.

Paul in AR

 

[Dario]

Paul,

I didn't install the gauge yet though I have one. But this particular vacuum is for aircon systems and capable of pulling deep vacuum.

You nailed it on the head...the bubbling does stop immediately (as soon as I close the valve) and starts as soon as the valve is opened. I thought these are bone dry already but seems like I am mistaken.

Thanks!!!

 

[pssherman]

Originally posted by Dario
<br />Paul,

I didn't install the gauge yet though I have one. But this particular vacuum is for aircon systems and capable of pulling deep vacuum.

You nailed it on the head...the bubbling does stop immediately (as soon as I close the valve) and starts as soon as the valve is opened. I thought these are bone dry already but seems like I am mistaken.

Thanks!!!

Blanks will ALWAYS have some moisture in them. The moisture in the blanks will be at equilibrium with the moisture in the air (humidity). IIRC 50% relative humidity will yield about 9-10% moisture by weight in the blanks. Even bones will have this moisture in them.

Paul in AR

 

[knottyharry]

Hi Dario,
Where did you get your vacuum pump.
Where would I start looking for such an animal.
Keep us posted on your findings.
Harry

 

[Dario]

Originally posted by knottyharry
<br />Hi Dario,
Where did you get your vacuum pump.
Where would I start looking for such an animal.
Keep us posted on your findings.
Harry

Harry,

I got lucky one day I visited the flea market. Found this under one table and bought it for $10.00 []. The seller even gave me a one week money back guarantee. The tubings and accessories actually cost me more than the pump at $17.00. I have the gauge but decided to install it later when I get more time.

I've been hunting for similar vacuum at eBay before hand the cheapest I've seen sold for about $70.00 plus shipping. It is heavy and with shipping, it will be over $100.00. Search for "yellow jacket" at eBay.

This looks promising.

 

[mwechtal]

Originally posted by pssherman
<br />Dario,
How much vacuum are you pulling? The vacuum pump that you are using looks like it could pull a deep vacuum. If it is pulling a deep vacuum then you are very likey evaporating the water still in the blank. The resulting water vapor will form bubbles just like air does. If the bubbles stop shortly after closing the valve and then restart when the valve is opened and the vacuum pump is on, then the bubbles are from water vapor not air.

Paul in AR

Paul,
You may be onto something there. That does look like a pretty stout vacuum pump. However I don't think that's water boiling. Water boils at 100 deg. C (212 deg. F), and acetone boils at 56 deg. C (133 deg. F). Now, I'm almost positive that the dissolved acrylic (plexiglass) will modify the boiling point, but it should still be lower than water. So, I think what we have here is acetone boiling. The bubbles will always form easier on a rough surface like wood, so it would look like something boiling out of the wood. Somebody with some chemistry experience less than 2 decades old please check me on this.[]

By the way, I hope everyone knows that acetone fumes are explosive. If that jar gets overstressed and breaks, it looks like a lot of vapor will be released. I would only do this in an explosion proof fume hood, or outdoors. I'm learning a lot here, and I'd hate to hear about losing someone in a huge fireball.[][xx(]

Mike

 

[Mac In Oak Ridge]

Mike, You got it right. Water will boil at about 160°F with 28" of vacuume. I find that acetone will boil at about 70° or even less like 55° when my set up pulls 28".

You leave it running and in about an hour you have lost about 25% of your solution and it is because it has turned to vapor and been sucked out of the jar.
Mac

 

[Dario]

This is getting more educational than I expected. Very good points and yes, I lost a lot of the acetone...probably more vapor than I cared for.

Anyone knows a cheap hose/tubing I can use to pipe out the (acetone) exhaust of the vacuum? I prefer plastic/rubber type but if nothing else works I am leaning towards copper tubing...don't want to put my set-up outside so I'll just vent it out.

Thanks!!!

 

[wdcav1952]

Originally posted by mwechtal
<br />

Originally posted by pssherman
<br />Dario,
How much vacuum are you pulling? The vacuum pump that you are using looks like it could pull a deep vacuum. If it is pulling a deep vacuum then you are very likey evaporating the water still in the blank. The resulting water vapor will form bubbles just like air does. If the bubbles stop shortly after closing the valve and then restart when the valve is opened and the vacuum pump is on, then the bubbles are from water vapor not air.

Paul in AR

Paul,
You may be onto something there. That does look like a pretty stout vacuum pump. However I don't think that's water boiling. Water boils at 100 deg. C (212 deg. F), and acetone boils at 56 deg. C (133 deg. F). Now, I'm almost positive that the dissolved acrylic (plexiglass) will modify the boiling point, but it should still be lower than water. So, I think what we have here is acetone boiling. The bubbles will always form easier on a rough surface like wood, so it would look like something boiling out of the wood. Somebody with some chemistry experience less than 2 decades old please check me on this.[]

By the way, I hope everyone knows that acetone fumes are explosive. If that jar gets overstressed and breaks, it looks like a lot of vapor will be released. I would only do this in an explosion proof fume hood, or outdoors. I'm learning a lot here, and I'd hate to hear about losing someone in a huge fireball.[][xx(]

Mike

Good point, and you also have to be concerned about the herd of Texans stampeding toward Dario's wood stash to save what they could!!! [:0][][:0]

 

[moose]

Dario,

If you were doing a fair amount of this would it be worth it to run the vapors through a condenser and reclaim it?
[^]

moose

 

[Dario]

Originally posted by wdcav1952
<br />

Good point, and you also have to be concerned about the herd of Texans stampeding toward Dario's wood stash to save what they could!!! [:0][][:0]

[)] Coach will have a big advantage []

Originally posted by moose
<br />

Dario,

If you were doing a fair amount of this would it be worth it to run the vapors through a condenser and reclaim it?

moose

Sounds expensive...if it is then it is not feasible.

 

[moose]

Dario,
Doesn't have to be expensive. [}]
All you want to do is condense the acetone vapors back into a liquid.
You just have to be making enough vapors for it to be worth it.

Have I got it right that the vacuum is causing the acetone to boil?

If so, and you had a collecting tube running up and off the vacuum jar. Then you would have no pressure worries about blowing the jar.

Next just have the collection tube start back down and enter another small jar and make a few coils, then exit. Put some ice in the small jar with the coils and you should be good. Have the tube exiting the condenser (jar with ice around coils) enter another jar for collecting.
All exit and entry points would have to be sealed. Does acetone eat cured silicone? If not then that would be a good easy way to do it.

In my mind small quart pickle jars would do the trick. Then you could just unscrew the lid on your collecting jar and pour it into some container to keep for another run or back into your vacuum jar to maintain your acetone level.

You could do this on a larger scale if needed. If the ice didn't do the job you could make a copper jacket that your garden hose would hook to then crack the hose so a little cold water is always going in one end and out the other and have your collection coils inside the jacket, exiting into a collection jar.

Wadda ya think? Clear as mud? []
moose

 

[moose]

Hmmm,
After reading my post I realize I have violated the vacuum by having the tube come off the top of the vacuum jar. It would have to come off the exhaust of the vacuum pump.
Don't know if that is feasible.

moose

 

[smoky10]

Originally posted by moose
<br />Dario,
Doesn't have to be expensive. [}]
All you want to do is condense the acetone vapors back into a liquid.
You just have to be making enough vapors for it to be worth it.

Have I got it right that the vacuum is causing the acetone to boil?

If so, and you had a collecting tube running up and off the vacuum jar. Then you would have no pressure worries about blowing the jar.

Next just have the collection tube start back down and enter another small jar and make a few coils, then exit. Put some ice in the small jar with the coils and you should be good. Have the tube exiting the condenser (jar with ice around coils) enter another jar for collecting.
All exit and entry points would have to be sealed. Does acetone eat cured silicone? If not then that would be a good easy way to do it.

In my mind small quart pickle jars would do the trick. Then you could just unscrew the lid on your collecting jar and pour it into some container to keep for another run or back into your vacuum jar to maintain your acetone level.

You could do this on a larger scale if needed. If the ice didn't do the job you could make a copper jacket that your garden hose would hook to then crack the hose so a little cold water is always going in one end and out the other and have your collection coils inside the jacket, exiting into a collection jar.

Wadda ya think? Clear as mud? []
moose

Moose that sounds like what we, in this part of the country, call a still. []

 

[moose]

smoky10 said,
Moose that sounds like what we, in this part of the country, call a still.

Well,
Yea, that's basically the idea. If you wanted to make your own Glen..um I mean Gasoline that's how to go about it. [}]

A quart of acetone cost me $7.00 and change the other day. If you start stabilizing a lot of blanks where your using a couple of gallons then maybe your giving up enough (the angel's share []) to warrant trying to keep it.

moose

 

[redfishsc]

Call around to paint (commercial, automotive, any kind of paint distributor) and see if you can get a 5 gallon of acetone. Likely much cheaper than the Lowes price.

 

[Glass Scratcher]

Originally posted by Dario

<br />

Durn if that isn't the same or similar model pump that the landlord picked up 5 yrs ago at a garage sale for about $3.00 and dropped on me to use for vacuuming air out from under masks.

Never have used the thing- the tag on the side that read ASBESTOS MONITORING SYSTEM kinda made me wary of the thing. I picked it up today thinking about using it as the landlord dropped in and he was upset that I was going to use his "Airbrush Compressor" as a vacuum pump. No disuading him as to what it was so I will be in search of a different pump. Maybe I will be visiting HF, I have a huge compressor so one of the venturi pumps might work just fine.