I built a cool cheap Vacuum Chamber

[akula]

Ok-
I am all set to cast up a butt load of camels (and palm tree trunks) in resin but the 1st pour had air bubbles in the ears. NOOO!!!
So I figured I'd get a small vacuum pump off ebay- 40 bucks and it pulls 20 inches too. Not bad..
Then for the chamber- A web search yielded a nice acrylic dome and plastic base at Deroberts.com 8" base and the dome is 12" high. $34 invested

Ok so I bore a hole in the top of the dome with the Dremel. Got some Evergreen plastic tubing, 1/4 inch and the telescoping larger sizes.
I attached the "hose nipple" with acrylic liquid cement and slid some larger sized tubing down onto the nipple's base and cemented those to the dome. Let it dry for a day and tried it tonight.

I sealed the dome to the base with 2 wide rubber bans installed on the lip of the base and slid the dome onto the base. I pushed the dome down over the rubber bands and hooked up the tube from the vacuum pump to the nipple. I truned on the pump and "hot damn Wilma" the pump pulled a sweet vacuum with NO leaks!!

"No leaks!!!" I let the pump run for a minute or so and shut the pump off. It seals the vacuum with a 1 way check valve. I saw the plastic base pull up as the vacuum built up and listened very carefully for any hissing around the base seal. NOTHING at all.

Air is a BAD THING when pouring resin in molds!!! Bad Air!!!!! BAD AIR!!!!

Now I will be pouring all weeked long... Camels and tree trunks. 1 gallon's worth!

Gordy- I still would like to get a set of camels to you to "pose" them and maybe show how to cut and modify the "stock" stance to a more life-like camel.
They are 1/35th scale too.



Bob

 

[Anders Heintz]

Hey Bob!

Sounds cool! Could you get some pictures for us to see your contraption? Also, any pics of your camel and tree trunks?

 

[akula]

Sure- I will dig up some pics of the chamber this week.
Gordy has the camel pics already... hint..hint

Bob

 

[Pete_H]

Hey MacGyver, that sounds way cool! Pictures of it would be cool. Perhaps more of us will make one as well.

Thanks for the info.

 

[JohnLea]

Be extemely careful. Vacuum can crumple railroad tank cars and shatter plastic sending pieces like shrapnel. I wonder if the dome was stressed when it was drilled?

Pressure is dangerous as well.

 

[akula]

Actually, I did not drill the dome- I did a pilot hole (divit ) using slow speed on the dremel. There are no stress cracks visible. Just to be sure- I coated the hole area with acrylic cement to seek out invisible cracks ( if any ) and put the sleeves over the hose inlet.

Remember- this is used to de-gas resin, so a full vacuum is NOT required. Just enought to break the bubbles free.

 

[JohnLea]

Oh.