Boxford A3 HSRi Axis overtravel and spindle overheating - help!

[Tom Aylwin]

Tom sounds like you have a few issues going on here. I can help but it will mean you trying one thing at a time giving clear replys to my questions and not going off at tangents.

Has this machine ever worked correctly while in you owned it. Or have you bought it like this.?

Can you run the spindle without CNC side being turned ON so we can identify if the spindle is getting hot and transfering heat to machine.
I don't see any speed controller inside the Control box you showed so I'm presuming the spindle has manual speed control or fixed speed.! Which is it.?
OR is there another board or electronics your not showing.?

Need you to CUT air WITHOUT the spindle running and at the normal feedrate. But I want you to NOT turn on power to the machine until last minute. Then quickly load program and start cutting air.
Take a note of the Stepper temps and check at intervals while cutting air to see if they get hot. And how long before they do. It's not unusual for steppers to get hot while stood at rest so this is why I need you to start from cold and check temps.
While cutting they should be just above warm to mildly hot, and when at stand still for ten to fifteen minutes be like holding a cup of tea or coffee after minute or so off boil.!! . . They shouldn't burn.

Try this and let me know.!

Hi JAZZCNC,
thank you for your reply.

I think this is the only other pic I have so including the previous - thats the guts of it.



Pretty sure its fixed speed spindle.

I will do the actions you describe today.
Assuming normal feed rate is the optimum one for the cutter and material (3.2mm dia bullnose, oak) therefore full feed rate??

For the record - Machine history:

Bought machine with video knowledge of axes moving manually and spindle turning on and off.
Having received it, on switching the power to the machine and pressing the homing button it lifted in the z axis, got to its limit, made a horrible noise (groaning) and didnt home.

On advice from Boxford I 'flashed' the [electronics] with the relevant program and that cured its homing issue. I still have to do this from time to time but have a suspicion the z axis proximity switch may be faulty.

From there I tried a few cuts at full feed rate and each time the machine aborted half way through having 'over-travelled'. What is slightly odd is that it looked as though the machine had lost its memory for a minute, dived into the work, come out again and carried on as it should..and then come to a premature stop!! Boxford were adamant this was impossible!

Since then I have made 8 successful pieces (landscape relief work) each taking about 6 hours - MACHINE RUNNING AT HALF FEED RATE (again on advice from Boxford)

Spindle collet always got very hot at full feed speed, less so at half feed speed (which allowed me to cut those 8 pieces). Now getting hot which ever feed rate.

2 days ago.... tried a cut at half speed. Did the first tool change and then it aborted half way through that finishing stage. Spindle collet and housing hot.

then...... after letting everything cool, (still on half speed) started from that same tool and let it follow the already cut second stage - ie cutting air until reaching where it left off - but it aborted before it got there. Spindle hot.

Yesterday, ran same program with spindle off and no material in place. It finished the job. Noticed how the x axis stepper motor got too hot to touch.