5 Aug
2008
5 Aug
'08
11:16 a.m.
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?
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.
I have a racing go-kart frame which is currently missing a motor (a CRG
if anyone cares). It occurred to me that it might be fun to grab a
large number of high capacity batteries and somehow rig one of the tape
drive motors to the live axle. I assume via a reduction gear and chain.
(clearly math needs to be done, but I want to start by finding the right
motor)
I would imagine several versions, starting with the simplest version but
moving to something where both rear wheels are driven and having some
sort of "software differential" and the moral equivalent of compression
braking.
no doubt there is something like alt.cars.electric-karts where I should
go with this, but I thought i'd ask about the tape drive motors first.
Anyone know what their specs are approximately and if they would be
appropriate?
(my goal is to be able to smoke the rear wheels and then turn on the
traction control :-) clearly I've been spending too much time on the
Tesla and Spacex web sites :-)
-brad
5 Aug
5 Aug
11:31 a.m.
>>>> "Brad" == Brad Parker
<brad at heeltoe.com> writes:
Brad> This has only a little to do with classic computing, but it
Brad> seems like it could generate epic amounts of email, so what the
Brad> heck...
Brad> Does anything know much about the construction and capacity of
Brad> a typical 9 track tape drive motor? Like the big 1 foot x 6"
Brad> tubes which I've seen a kennedy or DEC drive?
Brad> I don't know anything about how they are constructed, but I
Brad> assume they are high RPM and high torque. And probably some
Brad> sort of DC stepper.
Brad> I have a racing go-kart frame which is currently missing a
Brad> motor (a CRG if anyone cares). It occurred to me that it might
Brad> be fun to grab a large number of high capacity batteries and
Brad> somehow rig one of the tape drive motors to the live axle. I
Brad> assume via a reduction gear and chain.
I believe they are servo motors, not steppers. Yes, pretty high
torque. Not all that high RPM for the reel motors, higher for the
capstan motor (if you're looking at vacuum column drives with
start-stop capstans, as opposed to streaming drives, or drives like
the 360-era IBM ones that had continuously turning capstans and
solenoids that would push the tape against the capstan).
I would assume they only a few hundred watts if that -- considering
that they are run from low voltage supplies (12 volts or so) with
drive transistors that are likely to be good for order of 10 amps or
thereabouts. Not bad for spinning tape drive parts, but probably not
good enough for a go-kart.
Maybe Tesla has some castoffs? :-) Now *that* is a high power
motor...
paul
3:43 p.m.
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
6 Aug
6 Aug
4:16 a.m.
On Tue, 05 Aug 2008 11:16:14 -0400
Brad Parker <brad at heeltoe.com> wrote:
I have a racing go-kart frame which is currently
missing a motor (a
CRG if anyone cares). It occurred to me that it might be fun to grab
a large number of high capacity batteries and somehow rig one of the
tape drive motors to the live axle.
Even more OT, but real fun...
A 500 hp electric motorcycle build for drag racing:
http://www.killacycle.com/
To your question: The motors found in 9 track tape drive are a few 100
W at best. Not enough to drive a go-kart. These motros are more optimized for precision
then power.
--
tsch??,
Jochen
Homepage: http://www.unixag-kl.fh-kl.de/~jkunz/
5827
days inactive
5828
days old
3 comments
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participants (4)
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ard＠p850ug1.demon.co.uk -
brad＠heeltoe.com -
jkunz＠unixag-kl.fh-kl.de -
Paul_Koning＠Dell.com