|Forum topic by rockindavan||posted 02-22-2014 12:28 AM||3623 views||0 times favorited||11 replies|
02-22-2014 12:28 AM
Last night I picked up a blower that I plan on using for my dust collection system. It was hard to tell from the craigslist pictures, but he said it was “commercial grade”, whatever that means. After a quick look when I got there I realized it was a home made unit, but most of it was relatively robustly made, just lacking on the engineering side of things. The motor is a 1 1/2 hp powermatic, which I think came from a contractors saw.
The impeller on it is massive at 16” by 5” deep made out of 1/4” aluminum. I immediately realized after taking off the cover that this could be problematic. There is no way that motor will last without long runs to keep resistance high enough to let the impeller spool up.
My thoughts are to either cut down the impeller to a more manageable 12-14” so I don’t overload the motor, which would be a pain to do without completely ruining it. It is relatively balanced, although it could use a little work. The other option is to play around with pulley size to slow the impeller rotation and provide more motor torque. I’m a bit worried it could affect the amount of airflow, but the bigger impeller might make up for it.
Anyone have any suggestions or am I on the right track with reducing the speed? I don’t have any ducting yet so I can’t run it to measure air speed and amp draw yet. It blew the 20 amp circuit in about 5 seconds running without hose, so I don’t plan on trying any more free air tests.
I am planning to hook it up to the SDD and run 5” lines. The inlet/outlet are both 6” on the blower, but i’m not sure I could get sufficient airspeed with 6” lines. I do plan on upgrading to a nice 5hp cyclone once I can get 220V in a few years (I’m renting now and can only get 110V) but I would like to have something until then. Before anyone comments on the dangers of homemade impellers, I am aware, and the blower case is pretty thick steel, and I will likely build a secondary enclosure around it.