I'll try correcting the diode first.
Would that greatly increase the collector current if R1 is dropped to 100ohms? I just fear I might cause an accident. This motor with a centrifugal fan is rather fierce.
I suppose it's got a TO220 casing, such as most regulators. I'll need to on this vacuum for as long as my robot is moving around the room. I fear it may not even last as long as 5 minutes with this much of heat.
Yeah, the transistor marking is facing me.
Connect the diode between 1 & 2 to the nodes in the diagram or 1 & 2 of the transistor (1-B, 2-C, 3-E)?