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View Full Version : Boxford 125TCL Stepper Specs required.!!



JAZZCNC
31-01-2013, 05:40 PM
Hi Can anybody tell me the Volts and Amps of the standard steppers used on Boxford 125tcl.

Retro fitting with Mach and new drives and Would like a bit more speed from it so hoping to run with higher voltage but to save me some grief with trial and error then any advise for what worked for you welcome.

Also think the Diode on the Gemini speed controller has fried because was playing with it in Manuel mode before ripping guts out when the bloody thing started going Snap crackle pop.!! . . Now the board still lights up but Not starting spindle.? Think it may be fubard but not checked it out properly yet.! Any comments or suggestions for a replacement if it's Kfukd.?

Also need a Chuck has it don't have one. No experience with these little lathes and the spindle doesn't have threads just threaded holes in the front face so any Decent close up pics of the old one and how fastens would be most welcome. Along with source of replacement.!!

i2i
31-01-2013, 05:51 PM
Jazz, the spindle board has 2 polyester film caps on it that fail all the time, replace them with modern equivalents and it should work again.

The stepper drives are probably only run on 24v, so they could do with upgrading. Are they black heatsinked blocks or passive open board types.

JAZZCNC
31-01-2013, 06:24 PM
Jazz, the spindle board has 2 polyester film caps on it that fail all the time, replace them with modern equivalents and it should work again.

They look ok but will do for the little they cost. Thou to be honest the bloody thing lit up like a Xmas tree for the fraction of second it took to hit E-stop and the sparks and smoke seemed like it came from below the heat sink plate near the Big diode.


The stepper drives are probably only run on 24v, so they could do with upgrading. Are they black heatsinked blocks or passive open board types.

Seen that the CNC doctor shows the my setup has Half step unipolar drives. I've ripped the drives(passive) out already which used approx 28V and will be using some modern drives, probably M542.
The steppers are 8 wire so I'll probably wire them Bipolar parallel but not sure on Amps or how much voltage they'll handle. I've got a 42-44V supply I'd like to use but think those little motors may not like that much but with a bit of trial and error I could figure that out but if someone had already used modern drive would save me the hassle.!!

i2i
31-01-2013, 11:33 PM
That does sound terminal for the spindle drive. A sprint 400i drive would be suitable as a replacement.

If the drives are the gs d200s, they're not too bad, but they can be a bit sensative to overheating.

JAZZCNC
31-01-2013, 11:47 PM
That does sound terminal for the spindle drive. A sprint 400i drive would be suitable as a replacement.

Only single direction thou and want both directions really. Was thinking something like the KB Kbic.?


If the drives are the gs d200s, they're not too bad, but they can be a bit sensative to overheating.

No idea but would say so has it's one crappy looking board but they are out and won't be coming back.!!

John S
01-02-2013, 12:00 AM
Motors will be all right with 542's

Even if they are low voltage motors, say 3v then running voltage can be up to 20 times rated voltage so 60 volts which is well within the 542's range.

JAZZCNC
01-02-2013, 12:19 AM
Motors will be all right with 542's

Even if they are low voltage motors, say 3v then running voltage can be up to 20 times rated voltage so 60 volts which is well within the 542's range.

Ye I don't have any worries about them really John has they look nice enough motors just would have been nice to know specs. I'll figure Amps out from how they perform and sound.

John S
01-02-2013, 12:28 AM
There is a formula for finding the amps out, forget what it is but it has some square roots in it, ear of bat, tongue of newt and something to do with virgins blood so i don't suppose that's any good to you seeing as the last know sighting of a virgin in Yorkshire was in 1922 on the works outing to Cadburys.

That's if you don't count the East coast main line trains.