Weird sander problem...

[kbeitz]

Today i had a strange problem... I put down a new floor in my home and I was using a belt sander to sand the floor. I had this great idea of hooking my my central vac to the exit to the dust bag on my sander. When I turned the sander on it would not run with the vacuum turned on. Made no sense to me. if anything it should have run faster. Even if I turned on the sander first then the sander it would stall the motor right out. Any ideas? 

[furu]

Were they on the same circuit?  If so and even with the CB not popping if the cord length is long enough you might be getting enough voltage drop that the motor stalls out.  When you say belt sander I can envision a small hand sander and I can envision a large floor model that is VERY capable.

[kbeitz]

Not a voltage drop... Every time I pulled the hose away from the sander to motor would pickup speed. The vacuum would pull down the sanders motor dust fan. But you would think that the fan would be turning the same way as the vacuum pull.

[A.O.]

Is the vacuum sucking the belt up tight to the frame of the sander and not allowing it to spin maybe?

[Ox]

Strange...one WOULD think it would help speed things up if only a bit...

Maybe it has something to do with a sort of Coriolis effect?  You know how water will corkscrew down a pipe?  Maybe same thing with the vacuum and air and it's fighting the fan somehow...  Maybe try holding the vacuum off the sander's dust port just a smidge and at different angles.  You might find a position that will work, then fab something up to hold it that way.

Or maybe make up an adapter that goes from sander port to vacuum hose but has some holes drilled in it to allow "fresh" air to enter into stream.  Might keep things humming along.

Keep us posted - I'm interested to see what happens.