Erik Lotoszynski wrote: > > Can anyone tell me a good source of vacuum pumps at a > reasonable price? I'd like to build a vacuum system. > Also a source that explains how to build it, what > parts are necessary, and where to get them. > > Has any one tried the hand auto vacuum method with > success. I would also consider this. One of our club > members has tried this without success. He said he > had a hard time keeping a constant vacuum. Maybe the > bag he was using was the problem? > > Any thought or ideas are appreciated.
Don't bother with the hand-pump. Try E-Bay, search on "Gast". Don't pay more than $100 for any pump. Expect to pay $25-$75 (typical). I have a Gast two stage rocking piston pump. It can suck down to 30 inHg no problem. Plenty of volume too. The Gast diaphram pumps are popular. They are very low volume though, and can do about 24 inHg. The diaphrams are cheap to replace too. The PSC versions are better than the more common ones with shaded pole motors. Rotary vane pumps are also great as medium volume/pressure compressors for paint sprayers (make sure to put a filter on the output, as all rotary vane pumps lose carbon dust from their vanes). These don't develop as much vacuum (20-25 inHg). I'll plug my schematic for a long-life vacuum switch: http://isoar.ca/~andrewm/vacuum.html keeps the contacts from arcing. -- Andrew E. Mileski Ottawa, Canada RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED]
