9 track tape drive motors - suitable for a go-kart?

[Tony Duell]

> 
> 
> This has only a little to do with classic computing, but it seems like
> it could generate epic amounts of email, so what the heck...
> 
> Does anything know much about the construction and capacity of a typical
> 9 track tape drive motor?  Like the big 1 foot x 6" tubes which I've
> seen a kennedy or DEC drive?

The ones I've seen were a little smaller than that, but quite large 
none-the-less

> 
> I don't know anything about how they are constructed, but I assume they
> are high RPM and high torque.  And probably some sort of DC stepper.

THey're normally permanent-magnet DC motors with conventional commutatior 
and brushgear. The capstan motor may well have an ironless rotor (so that 
it turnes more smoothly with no 'cogging'), the spool motors are normally 
more conventional.

I don;t think any of them would have the power for a go-cart. In general 
wound-field motors develop more torgue than permanent magnet ones 
(althogh I've worked on cars with permanent-magnet starter motors, so 
you can get sizeable torques using modern permanent magnets). Typically 
tape drive motors take a few amps at 12V or 24V, I would think a go-kart 
motor would take about 10 times the current at least.

-tony