"We are going to buy a vacuum chamber very soon..." Topic

Yes, buy one, not make one. We've decided that we need a vacuum chamber to get better pours and molds, and I don't want to fiddle around with a bunch of parts trying to get it to work, or worry about leaking O-rings, etc. So, please don't send me any DIY info on making one.

That being said, we are looking at a 5-gal pot with a 12-inch interior diameter that can achieve 29-inches of mercury in about 2 – 2.5 minutes, and maintain it. It's a benchtop unit and is supposed to be relatively quiet and easy to maintain.

Our budget is $300-$500, including shipping and taxes.

If you have a new (or used in good condition) unit, or know someone who sells them or makes them, please contact me either through this forum or at my e-mail address:

mmitchell_houston [ – a – t – ] yahoo [ – d – 0 – t ~ c – 0 – m – ]
And yes, I'm really scrambling up my e-mail address to try to fool those spambots, which are just getting smarter every day.

Thanks in advance for your help.

Mike

I too would be interested in this only i'm in the UK. my google fu is only turning up systems over £1,000.00 GBP

Brandlin, there are plenty that are less expensive here in the USA (like those I linked to at ebay). I'm just shopping around because my mama always told me to!

i looked through ebay – very little in the UK… :(

sorry for jumping on your band wagon… just thought i might get some info…

If your serious, and have some $$ to put towards it then try this:

link

They have several that are very well made, and in different shapes. I am saving up for one of the cubes so I can put shelves in it for mass casting.

You can also get them made with an attachment that connects to a metering mixer so you are pouring the resin into the molds in the vacuum chamber after it has already reached a vacuum.

Another pieces of equipment that I now feel is a "must have" is a metering mixer. You can get 100% accurate mixes without adding air into the mix by stirring, and it's a lot faster. No more tubs, sticks and spilled mixes. Since the containers are also kept sealed you will not get air contamination in your resin as well.

link

There are a lot of other companies out there that have mixers, just shop around till you find what you need. A gear driven mixer I think is better, since you can get a continuous flow for filling larger molds.
Other mixers you have a set "shot size" so you have to keep filling until the mold is filled, with a gear driven mixer you can continue to pour and mix resin until you take your foot off the pedal.

For a vacuum pump, if you don't already have one, it's best to get something in the 8-10 CFM range. There are many pumps out there, but 2 stage pumps are and pull what they call a "deep" vacuum. Less likelyhood of small remaining bubbles in the corners (vacuum casting can never get ALL of the bubbles out).

MechanicalHorizon: Thanks, but that's just out of our price range right now. But man, they do have some neat stuff, don't they?

I purchased this one. I do not use it on an "industrial level" so I am not sure what the wear and tear on it may be.

link

mmitchel:
We have used a Vigor chamber for years. When new it was about $700 USD and is all self-contained – chamber, pump, table platen etc,,,. The chamber measures 9 inches diameter by about the same in height. Looking at a new system today the same rig jumps up easily into the $1000+ area. Used ones are not that cost affordable either when and if you find them. In order to 'pull' a vacuum in the size container you list you're going to have to go with more powerful components or some kind of chamber setup the dairy industry uses which goes in the multi-thousands. Both the component and the high cost roads appear to knock themselves out of the running according to your criteria. If that's the case, you're simply not going to be able to get 'there' from 'here'. Rather you're going to have to either lower the quantity level of material you want to vacuum, or raise your dollar level, or keep trying the used market and hope you luck out.
I do not know what quantity or material you ultimately want to vacuum. Saying that, you can make smaller multiple vacuum batches for large molds for RTV. I made a 35 pound RTV mold once by using that method – about 4 pounds max each cycle. It took awhile, but it worked.
Your best bet is to search around the RI down to NY corridor. That is still the center of the rubber mold/jewelry trade and the best place to find what you ultimately will settle for. Check Conley Casting (Warwick RI), Contenti (Providence), Tek Cast (they used to be in New Rochelle NY). Go on the web and check out used industrial supply houses thruout that area. Talk to the folks at the 3 places I list – tell them what you need – and specifically ask them if they know of any secondary used sources.
Toby Barrett, Thoroughbred Figures