Why Not Use A Dust Collector

[partsman]

I have been doing a lot of research here on vacuum table designs & found lots of "DIY vacuum table" posts. It seems everyone is either going the $5K to $10K commercial vacuum pump route or they use a Fein or Shop-Vac type product as a hold down system. Why do I not see more/any using the larger 2 to 5 hp dust collector type systems as a hold down. I found several at Grizzly that advertise around 2300cfm & a static pressure rating of 16.7" or more for under $500. I'm sure there is a reason no one is using them but why? What am I missing?

[a4drvr]

Probally because, unlike vacuums, dust collectors are not meant to suck, their meant to move air. Suction is pretty much a by product. Too much suction/restriction will over speed the impellar causing possible damage to the DC. Now granted, I may be totally wrong, but everything that Ive read on DC's shows that this is what would happen.

[Geof]

....a static pressure rating of 16.7"...

This static pressure rating is the height the thing will suck a column of water; full vacuum is around 384 inches of water so these dust collectors can pull not even 5% of full vacuum. This is simply not enough.

[BobF]

Static pressures on a good vacuum cleaner can be over 100". The Fein Turbo lists 99 inches.

[wcarrothers1]

yep dust collectors do not "Suck" hard they move and filter a large amount of air (ie because they suck lots of air through the larger tubes).. Think of it a as their impellor moves lots of air how ever lacks the sealing to suck hard. Or thinkof it as if your car motor would suck in less air if the piston rings were realy loose.

b.

[partsman]

I knew there had to be a reason. I was just not sure what it was. It looks like I was comparing inches of h20 to inches of HG. Thanks for the clarification.