Vacuum pump

[mars]

Hi, I would like to have your feeling on Vacuum pumps.
At this time I'm using two motors (Lighthouse Lh676565-OD-240) my spoil board measure 54x108 and separated in 8 sections.
It's giving a reasonable amount of suction, I'M having problems with motors burning up on me, and this is the second one in not so many hours of use.
I have found a regenerative blower on EBAYhttp://www.ebay.com/itm/380390423887 Siemens ELMO-G 1.3kw (1.74HP) 2BH1 500-1AF19, would you think that one of these or similar could give the same or better performance than the two Lighthouse I'm using.

I would like the real vacuum motors suggested by Shopbot but my budget doesn't permit it and further more I don't have 3 phases, the farthest I can go in my shop, is a 5HP motor.

If you have other solutions, I will be glad to take a look at it.
Thank you for your help

[steve_g]

Marcel...
I'm just curious about your vacuum motors burning up... Do you have a bleeder hole/valve to always allow some cooling air to the motors?

FYI the eBay pump is 3 phase.

SG

[mars]

Thank you for the reply
Yes I have a 3/8 bleeder hole and the motor is in open air.
The air intake is in seal box and on top of this box there is an inlet for the fresh air that is connected to a tube with a valve that is about10 feet away, when the motor is not in use I shut this valve to avoid dust to come in the motor.
About the blower on EBay, if I can find one that is a single phase with about the same specs, would it be better than the Lighthouse

[steve_g]

http://www.gd-elmorietschle.com/uploadedFiles/Elmo-Rietschle/Downloads/Content_G/DaBl/2BH1500_usa_060509.pdf (http://www.gd-elmorietschle.com/uploadedFiles/Elmo-Rietschle/Downloads/Content_G/DaBl/2BH1500_usa_060509.pdf)
If this is the right data sheet and if I'm interpolating graphs correctly... (I'm not very sure of myself here...) It appears that one vacuum motor is about equal to this pump. This is not my area of expertise and I welcome correction or corroboration by others!

SG

[dlcw]

Hi, I would like to have your feeling on Vacuum pumps.
At this time I'm using two motors (Lighthouse Lh676565-OD-240) my spoil board measure 54x108 and separated in 8 sections.
It's giving a reasonable amount of suction, I'M having problems with motors burning up on me, and this is the second one in not so many hours of use.
I have found a regenerative blower on EBAYhttp://www.ebay.com/itm/380390423887 Siemens ELMO-G 1.3kw (1.74HP) 2BH1 500-1AF19, would you think that one of these or similar could give the same or better performance than the two Lighthouse I'm using.

I would like the real vacuum motors suggested by Shopbot but my budget doesn't permit it and further more I don't have 3 phases, the farthest I can go in my shop, is a 5HP motor.

If you have other solutions, I will be glad to take a look at it.
Thank you for your help

I've been using the Lighthouse motors since 2009 and had only 1 burn up because I didn't have enough cooling air through a bleeder hole. At 2500' altitude I pull about 7.5" of vacuum. At sea level I know people are getting up to 10" or 11" of vacuum. The pitfalls of living in the mountains...

I built one of Gary Campbells Black Box Vac Source (http://www.talkshopbot.com/forum/showthread.php?t=11813&highlight=Black+vacuum) a couple of years ago and it was the best thing I ever added to my setup. I have 7 zones (only use 6) on my PRSAlpha 60x96 bot. I cut a lot of 60"x60" baltic birch and 4x8 sheets of plywood. I have butterfly valves to open up a 1/4" source of air for each motor that is running. I currently have things setup to run two motors for primary hold down and can bring in two more motors for additional hold down. The only thing I have a little problem with is small parts cut from prefinished American maple plywood. Slippery material.

[Gary Campbell]

Marcel...
I received your PM and will respond here as it may clarify things for some others. My experience tells me the following:

1) I had much better results on a 4 by 8 plenum with 4 motors than with 2. Your table is even larger than mine. My personal rule of thumb has been one motor per 2' by 4' vac zone.

2) The pump you list above is, like Steve says, about the same specs as 1 of the LH brand motors. Mfgr's specs say it is 3 phase, there may be a single phase available, usually at a higher price

3) I cant speak specifically to the LH676565-OD motors, but as a rule, if you are burning them up in less a couple years, then you have something wrong. There are hundreds of them in daily use and they outlive their published lifetime by 3 or 4 times. I had thousands of hours on mine without a problem. My designs have paid more attention to cooling of the motors than quieting them. This results in higher performance and less heat. (slightly higher noise also) If you need quiet, buy a Fein.

I have partnered with a friend that is manufacturing my latest design and selling them as both OEM and aftermarket to end users. This latest design is smaller and lighter than the almost 200# that the 1st design was, making more shipper friendly. Using my "ol standby" LH7123 motors, in combinations of 2, 3 and 4 motors (single and dual stage) in an all new PVC enclosure with easily removed panels for motor access. Thermal overload (breakers) built in the switch panel and filtered motor cooling and exhaust, along with relief valves to ensure circulation without decreasing vacuum as a simple hole will, have been added also. They may even have a "bolt on" design for ShopBot models as they have done for other brands.

There should be a www.blackboxvac.com (http://www.blackboxvac.com) website up soon. If not then here is a link with the contact info: http://www.cnczone.com/forums/camaster/191192-black_box_vac.html