Last night my blower motor locked up. I know why and how it happened.
I attached the blower motor directly to the back of the box in which I do the painting.
According to the information provided to me by rjbass, the motor should be segregated from the box. In other words, it should be detached completed and housed in a separate box. You build the booth, and connect it to the separate box (which houses the furnace blower/exhaust fan) by using 4 inch corrugated hose, and then exhaust it outside with another section of 4 inch corrugated hose.
What happens if you attach the exhaust motor directly to the paintbooth is the squirrel cage collects the particles from your paint work and eventually begins to wobble. In my case, the wobbling was minor, but the paint particles eventually got into the bearings despite the filters I used, and last night it began to squeal a bit and finally locked up and quit about the time I was done (luckily).
If you segregate the exhaust unit, the 4 inch corrugated hose collects most of the particles on the ribs inside the hose, before the particles can reach the motor, because the stuff is heavier than air and the air tends to cause the paint particles to dry on the longer journey to the motor and beyond to the outside atmosphere.
I'll go about getting another furnace blower unit and some hose, and I'll be back at it in not time, but I thought I'd share this info for anyone thinking of building their own.
The video clip rj sent me said this would happen eventually, but I had built the paintbooth already and figured I'd use it till it quit. It took about 50 baits before it locked up, which is alot when you think about how much primer and paint I threw throught it.
...Back to the drawing board...