Cheap reliable vacume chamber

C

ciphery

Joined
Feb 13, 2007
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73
Take an air compressor and remove the airfilter. This is usually about a 1" pie thread atatchment.
with plumbing fittings reduce the 1"? NPT (national pipe thread) fitting to acept a 3/8" hosebarb.
Attach a hose to this(about 3' should do it)
Take a 8" stainless steel canister (kitchen flour/tea/sugar canister 9$ at a harware store,I used one that has a plexiglass lid and has a rubber gasket on it with a hasp to keep the lid shut(like on a grolsh beer bottle) gluethe gasket down to the lid with silicone) drill a 1/4" hole in the bottom of the canister along with 4, 3/16" holes to accept 10-32 machine screws. take a 1/4" NPT pipe flange and atatch it to the bottom of the canister with the 10-32 machine screws, appling a gasket of silicone between th flange and Canister as well as arround the heads of the screws to prevent vacume loss when in operation.
next thread in a 1/4" short pipe nipple into the 1/4" pipe flange that you just attatched to the canister.
Onto the 1/4" nipple thread a 1/4" pipe"T" fitting one end of the "T" fitting should have a 1/4" NPT vacume gage on it to tell you how much negative presure(measured in inches mercury)you have when using the vacume chamber.(at least27" for a good stabilizeation affect).
The other end of the"T" fitting should have a 1/4" valve to shut off the conection between the Vacume chamber and the compressor(now a vacume pump)
into the 1/4" vale thread a 3/8" hose barb and conect the line between the compressor(now a vacume pump)and the Canister(now a vacume chamber)
I made a little stand out of wood to hold the canister from rolling arround while in use and also made a little tray/rackout of expanded aluminum to fit insideto keep work off th inside of the canister.
To opperate simmply open all the valves on your compressors air tank (take drain incl) turn on with the work inside the chamber and watch the vacume gage. when the gage reads 27-28" of vacume shut the valve between the compressor/pump and canister/chamber OFF. and turn of the compressor . if you did all the fittings,gaskets and doors up tight the chamber shopuld hold a good vacume 27" of vacume for atleast 24 hours while your glu dries if not you will have to reseal and or run the vacume pump from time to time to keep the vacume up in the chamber.
I WILL TRY TO POST A DIAGRAM OF THIS SOON FOR YOU ALL TO SEE IF YOU ARE LOST ON MY VERBAL DESCRIPTION. TILL THEN HAPPY STABILIZING:)
 
Is there any threat of damage to the compressor from sucking the fumes and perhaps vapor from the stabilizing medium through it?

Dave
 
if you do manage to suk up the medium yes (glue valves in compressor shut/open)but that should not happen. You could put a inline fuel filter in the middle of the vynal hose to prevent the sucking up of forin materials. the vapors however will not hurt the compressor. although you may want to un hook the air tank just too keep the vapors out of the tank in case you use something that gives off flamable vapors. (YOU would not want a build up of say acetone vapors in your compressors air tank) but as stated before the tank drain should be OPEN so as not to store these vapors under pressure.
 
the compressor also only runs for about 20-30 seconds inorder to evacuate the chamber of air.
 
I've been meaning to build one of these Venturi Vacuum systems someday: www.joewoodworker.com/veneering/welcome.htm

The designer claims it will produce up to 21" of Hg and cost's about $170 to make (not counting an air compressor if you don't already have one).
 
What would you need a vacuum chamber for? vacuum bagging stabilized wood?
 
Just a note of caution on a few things:

This will indeed draw a good vacuum.Remember,the valves and rings on most compressors are made to take presure in one direction only,so there may be excessive wear on these components.

Vacuum pumps have a special high viscosity and very high vapor point oil. The oils in many compressors will boil/vaporize at 27" vacuum.

If using this system with CA glues to stabilize wood/bone be aware that the vapors will react with the oils in the compressor. That is exactly how the forensic guys and gals find fingerprints on items.Over a period of several uses it could ruin the compressor.

Only use a vacuum container that will withhold the extreme external pressure created by high vacuum. 27" of vacuum will crush a light weight container (and shatter a glass jar).
Stacy
 
bladsmth said:
Only use a vacuum container that will withhold the extreme external pressure created by high vacuum. 27" of vacuum will crush a light weight container (and shatter a glass jar).
Stacy
Click to expand...

I want to stress this point along with Stacey who has also worked in a chemistry lab. Overbuild your vacuum chamber, and don't use a glass jar if at all possible. imploding glass = no fun.

:)

-Darren
 
To be more to the point....27" of vacuum (not likely with this setup) will crush a 55 gallon drum! I use a lexan bell jar 1/4" thick.
Stacy
 
I was just discussing posting on this topic with Darren, since he offers Nelsonite, the material I use in my setup. This is not to take anything away from the already mentioned ideas of inexpensive alternatives but I would share what I came up with to do all my natural handle materials.

For some time now I have been soaking my handle materials in Nelsonite, it is a wood stabilization product developed for the furniture industry in Grand Rapids Michigan, it is kind of like an industrial strength Thompson’s water seal. It seems to stabilize wood quite well without turning it into plastic, in fact the only way I can tell it has been treated is a slight Nelsonite smell when you grind the material.

The manufacturer suggest just applying the stuff with a brush, but Dr. Lucie got me to soaking stag, wood and ivory in jars of the stuff. I had my doubts it was getting good penetration on some of the denser materials so I wanted to try it under vacuum.

I got the idea for a good chamber from my friend Bill Sowell last summer at the ABS Mid America Expo. I got on e-bay and started shopping. I managed to pick up a 2.5 gallon pressure pot for spray painting that was barely used for $45. Then I found a laboratory vacuum pump for $65, and a combination vacuum/pressure gauge for $35. The combination was something I wanted for reasons I will get into. So the entire setup after a few other parts cost me around $150.
vac1.jpg


Paint pots can handle the vacuum but the gasket was not designed for holding negative pressure, so I removed it and made a duplicate out of neoprene gasket material and polished all the edges of the pot that would contact it. I attached the gauge to the top, and put an inlet with a ¼ turn ball valve and a barbed fitting to attach my hose. I “borrowed” a colander from my wife that fits the inside perfectly and put some fold in handles on it so I can fill it with my materials and then lower them into the Nelsonite. I seal the lid down thoroughly and then attached the vacuum pump to the hose with the valve open and hit the switch. When the pump gets things to -20 inches of mercury I shut the ball valve and unhook the pump. Then the entire chamber is just the right size to go on a shelf for as long as I like. I have went as long as a month between batches and not lost a single bit of vacuum, I am actually quite impressed with that.

vac2.jpg


Now just to be certain, when it comes time to remove the materials I open the valve and allow the pressure to equalize and the add 20 PSI of pressure to the mix for around 10 minutes, before releasing it and removing the materials. I just did a test today and cut some wood across and lengthwise to find that the entire interior was fully saturated. This system seems to be working quite well for me.

Even if you don’t vacuum it the Nelsonite is a handy product that you can get from Darren Ellis. With any luck he will have some heat treating oils soon as well.
 
Cool! Thanks for posting that, Kevin. I'm going to try that. I like osage orange, and have lot's of it, but I don't use it much because it tends to shrink. This might be the answer. :thumbup:

Edited to add, I read Kevins post before the first one in this thread. Good info both places. :)
 
what other household containers will work for a vaccuum chamber? by any chance would a coleman propane camp bottle work for a chamber? if so i have 2 empty ones. im sure i can find a cheap priced vaccuum pump somewhere. if a pump from a vaccuum cleaner works i will use it. anyone know if the vaccuum cleaner pump will work and if the propane bottle will work. its one of those 1lb bottles. like for a lantern or camp stove and other camping gear.
 
tHANK YOU ALL FOR YOUR CONTRABUTIONS TO THIS THREAD.:)
That being said I do have a few details to add.
1: I used a CHEAP (1/4hp) compressor for this project. and have used it several dozen times with no noticeable ill effects.
2: I am awarr of the cyanic acetate glue+oil effect and the glue actually bonds to the ACID in the finger prints not the oil!
3: As I stated earlier an inline fuel filter will keep out forgin matterials from your compressor. and the inline valve between the compressor and the chamber limits the nessecary time that the compressor be used to only a few seconds! no real wear and tear. that being said you may not want to use your big $1000 dollar compressor.
4: I use a 6" dia X 10" long stainless steel canister with a 1/2" thick plexy lid.
If you do not feel comfortable with this arrangement than use another suitable container NOT GLASS!.Such as an old Pressure cooker from the good will or a dusty old corner of the pantery.
5: Do not attempt to open the unit before first SLOWLY releasing the vacume inside.
6: And most emportantly always inspect a pressure vessal for sighns of fatigue and or posable failure sighns(dents,rust,cracks,broken seals)
Use better judgement and if you donot posses such judgement do not use this project!
This is ment to be a usefull and safe thread so I do apreciate the input however I think the point of CHEAP has been lost on some ppl.
 
by the way how much square area does a welded seem 45gallon drum have again? and how much square area does a 6" seemless drawn canister have?
 
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