Dissolving Plexiglas?

[Mac In Oak Ridge]

Anyone out there that is dissolving Plexiglas in Acetone to make vacuum stabilizing liquid?

I put a few handfuls of Plexiglas in a quart mason jar and filled the jar with Acetone. The stuff just melted down to a big blob in the bottom of the jar. I stirred it up with a stick and let it sit 24 hrs.

The liquid on top was thicker than pure Acetone and I poured that off into another jar. Added more Acetone and stirred again. Tonight it will be 24 hrs. on the second addition of Acetone. At lunch time there still was a big blob of Plexiglas in the bottom of the jar.

Does the Acetone reach a saturation point that it won't melt any more? I plan on continuing to add Acetone allow it to dissolve Plexiglas and pour it off unless someone tells me I am doing something wrong here.

 

[rtjw]

never heard of this process. i would like to know more.

 

[Old Griz]

Yes, most solvents reach a point of no return at which it will not longer accept anymore material being disolved.. It sounds like you started off with way too much plexiglass for a quart jar.. you might end up having a gallon of solution when you are done... LOL..
Let me know how the experiment goes... I am real curious... I would think that you want the solution to be fairly thin so that it can be absorded into the wood via the vacuum...

 

[chrisc99]

I know this has been discussed before but forgive my ignorance when I ask what is the form of the plexiglass? is it a sheet that's broken or cut into pieces or can you get it broken down already?

 

[wdcav1952]

I tried this last year. I didn't have vacuum; I just let the blanks sit it a super-saturated solution of plexiglass dissolved in acetone for a week or so. The blanks would sink after a few days. It might be better with vacuum, but my results were poor in that the solution did not penetrate deeply into the wood.

Chris, I had some pieces of plexiglas from another project, and just broke up some pieces to use.

 

[Darley]

Originally posted by chrisc99
<br />I know this has been discussed before but forgive my ignorance when I ask what is the form of the plexiglass? is it a sheet that's broken or cut into pieces or can you get it broken down already?

Ask your local sign writer, they got all the time off cut or broken sign they change over a new one cut on to the BS and it's free

 

[ctEaglesc]

Originally posted by wdcav1952
<br />I tried this last year. I didn't have vacuum; I just let the blanks sit it a super-saturated solution of plexiglass dissolved in acetone for a week or so. The blanks would sink after a few days. It might be better with vacuum, but my results were poor in that the solution did not penetrate deeply into the wood.

Chris, I had some pieces of plexiglas from another project, and just broke up some pieces to use.

I drill a hole regardless of what "kit" I am going to use.
I woulnd't think that just "soaking" would work.
A Vacuum jar and a $10.00 venturi "pump" from HF works fine on my compressor.
Have you tried the search for info?
I know it has been discussed and the original article is in the archived posts.

 

[chrisc99]

Thanks for the info everyone. I did search the archives but could not find out if others were using scrap plexiglass or not. I just got my vacuum system finished. I used the mity-vac venturi pump from HF and a pickle jar (from vlasic). I'm going to give it a try with some really punky birch burl I have.

 

[Thumbs]

Mac, if you're using it with a vacuum pump, please let us know how it turns out. OK?

Hmmm, Eagle did you say you used this same formula? Did it work out ok, or did you use some other stabiliser?

 

[ctEaglesc]

Thumbs-
I use use the acetone plexi mix.
I dissolve the plexi with acetone.I use it mostly on corn cobs.I ahve been doing it that way since last fall.It WILL NOT replace a pressureized commercial set up.If you are filling the sells of the wood with a 50-50 mix, the acetone will evaporate so ther is a "void" where the acetone once oppupied.
I use it to replace the amount of CA needed as my mix is much cheaper.
I would suggest to get started pick up a 16 ounce can of Bondo wood hardner at the Borg.(Should cost around $7.00)
This will give you an idea of viscosity.
THere is no way I can explain what thickness I use as I don't measure anything unless I am baking bread.(probably one reasons why I don't cast resins).
My system is bare bones, but there is a site that has free plans to build an excellent home made unit using the HF "pump".(there are two sets of plans for different set ups.)I don't have the link, it went when the old computer went.
I belive Smoky Tom has made the same set up and possibly he can provide the link.
I did a search on this site for "vacuum stabilization" in archived threads.Quite a few posts, happy reading.

 

[Thumbs]

Thanks for the info guys![]

 

[Fangar]

I use a simple vacuum hand pump for bleeding brakes that I got at HF. It works great. I expoxied a gas fitting through the lid of an old pickle jar (About 1 1/2 quart). For now I have been using straight polyurethane, with positive results. I think I will try the plexi mix some day. Here is a photo of my rig, but with a smaller jar that I started with.

Cheers,

Fangar

 

[Old Griz]

Fangar... you might want to be a bit more careful using the plexi/acetone mixture with that pump, the fumes may do in your seals.. just a thought

 

[J. Fred Muggs]

Boy, I musta missed this original post back in April.[B)]

Here's the link Eagle is referring to. http://www.joewoodworker.com/
They have plans for a venturi operated vacuum system or pump operated system.

I've used the Bondo Rotted Wood Stabilizer on corn cobs using a vacuum pump at 26" Hg. Like Eagle says, the solution only partially fills the pores. But, it saves aplot of much more expensive CA glue.

Saturation was pretty thorough on corn cobs but left a lot to be desired on wood blanks. Punky wood soaks it up pretty good also, but more solid wood is tougher. Denser woods are very difficult.

I have a batch of the dissolved plexi ready to go but no shop time to try it out. Yes, the acetone reaches a saturation point where it will no longer dissolve the plexi. For me the viscosity was about like cream - thicker than water or milk. Maybe that relationship will help. Pour in fresh acetone and keep it going til all dissolves.

I simply cut up some old plexi in small enough sizes to fit the gallon jar I was using. Some had the protective paper stuck to it. The paper comes loose in minutes after the acetone hits it. My batch was a litle bit dirty looking probably because of the paper, but not enough to discolor the blanks.

Based on the label, I believe the Bondo to be little more than plexi in acetone with some MEK added probably to retard the drying.

I am thinking after my first experiments, that it might be best to apply a vacuum to the blanks in solution until the bubbling ceases, then relieve the vacuum for a time and re-apply the vacuum, going through several cycles of this. Reason being (my thinking aloud here), Vacuum sucks air out, return atmospheric pressure to blank to push liquid in, vacuum again sucks more air out, pressure again pushes more liquid in. I did two cyles of this on a few corn cobs and they seem to be heavier than the single cycle ones.

Just my observations to date. If ya'll can get me out of working (with pay of course), and out of teaching a lathe class, and everything else I gotta do, I might have time to finish these experiments.[]

 

[btboone]

Just be aware that the stuff should be extremely flammible. That's close to the way that napalm's made.

 

[smoky10]

I use an auto air conditioning vaccuum pump and manifold to pump down my 1gal. pickle jar. I have to watch what I'm doing because this pump will boil almost any liquid out of the jar if I have the valve wide open. I have to do it slowly. I have used it with plexi and acetone as well as with acetone and poly.
Here is a picture of my set-up.

<br />

 

[ctEaglesc]

I knew someone would have the link, the picture was icing on the cake.
If you are unsure of the viscosity it may pay to buy Bondo's first as I suggested, it will give you a tarting point. I felt it was too thin.It may save a lot of time and effort but it is of course up to you.

 

[Fangar]

Originally posted by Old Griz
<br />Fangar... you might want to be a bit more careful using the plexi/acetone mixture with that pump, the fumes may do in your seals.. just a thought

Good point. Griz. I will look into that.

James