Open Source Vacuum - cont.

[ljdm]

The specs look very good compared to the Feins. What kind of noise level difference is there? Also, what is the amp draw on the motor? Not starting amps, running. Trying to figure which way to go - 2 Feins, easy setup, low noise, less heat?, lower amp draw?, vs better specs, more work setup, lower cost, etc...........
Thanks for any info

[ljdm]

Another thought - anybody know if one or two Feins together has enough vac to lift sheet goods, with a couple of pods?

[scottcox]

Lou,

Frank Leinbach does this with a Gast vacuum pump. I would imagine that the Feins have enough power to do this.

See this thread for his setup..... (Scroll down)

http://www.talkshopbot.com/forum/mes...312/16412.html

[scottcox]

And another bit of info for this thread. I recently spoke to an engineer at Imperial and he said that the high temp issue could be avoided (or at least helped) by installing a vacuum relief valve just above the first motor (of two in series).

[fleinbach]

Lou,

Here is a more detailed thread pertaining to information regarding a vacuum sheet lift. I did not test my fein vacuums but I did test my 7.5 pump from Shopbot and it worked but it draws 14 inches of mercury. Since the Feins only draw 6" they would not be able to lift much weight unless you increased the 12" puck size considerably.

http://www.talkshopbot.com/forum/sho...4549#POST44549

[ljdm]

I'll probably just get a separate pump for the hoisting. Thanks for the info. Although after reading the posts, wondering if just a clamp made for sheet goods (similar to those used in lifting sheet metal) might be better, especially for MDF. Will have to experiment and see.

[harold_weber]

Scott, did the Imperial engineer happen to mention a discharge temperature limit for the blower?

[scottcox]

Harold,

He stressed that it's not so much a set temperature, but a condition of no air flow as being the killer. The impeller? spins "too" freely, creating heat very quickly thus deformation which destroys the housing.

He said a simple ball and spring type relief valve could be placed in the intake (or plenum) port and set to release just before maximum attainable vacuum (15").

In reality, this would be a safeguard from zero air flow, but from what I read, unless your plenum, spoilboard, seals, etc. are "perfect", there's always going to be residual air flow, correct?

I haven't had much time to pursue this, so I haven't sourced any of the relief valves yet. I think when the time is right, this is the route that I will take.

-Scott

[Brady Watson]

At the risk of sounding too practical - keep in mind that a souped up Cavalier isn't going to be a Corvette. If you want 'super duty' you need hardware from the beginning designed for that - and that gets pricey as we all know. So, that being said, if you burn out one motor per year, even 2 per year - So what? It's still cheaper than laying out thousands for a large pump. There are trade-offs to everything. I would imagine if you had the time and inclination to do so, you could make a heat exchanger or water jacket and liquid cool it...it's still going to be a Cavalier at the end. Use this type of setup to be able to take advantage of vacuum technology while keeping the investment down until you start making money. When you make some money, buy a professional setup. That's the whole idea here, I've tried to get across since I started this project.

-B

[eric_schumacher]

Here is a novel idea...

How about using a venturi vacuum, but instead of using one that is powered by an air compressor use one powered by water/liquid.

Something like this:

http://www.plumbingworld.com/minisuctionpump.html

Then instead of wasting water by running this off the garden hose create a closed loop system using a hot tub or spa motor and some barrels. You could even use propylene glycol or something similar as a liquid to reduce evaporation and humidity.

It's just a suggestion as an alternative. Not sure if this specific product can pull enough volume.

On advantage to using this method for other uses is that any evil fumes etc will be tamed by the water. This might be useful when using glues or vacuum removal of bubbles in two part mold making etcs.


I would think there would be an advantage to keeping most of the vacuum lines a small diameter. I see a lot of large PVC and have to wonder if that is efficient. I wonder if putting check valves on smaller diameter pipe as close as possible to the plenum would help with lesser expensive vac solutions.

Using a vacuum storage tank and a vacuum switch that could be used to either switch a vac unit on and off or to switch a valve that could switch between pulling from the system or atmosphere could help with weak pumps or pumps that would overheat when pulling max vacuum.