Hello Guest it is September 20, 2019, 08:48:14 AM

Author Topic: Bridgeport Knee Mill Conversion?  (Read 159130 times)

0 Members and 1 Guest are viewing this topic.

Offline Hood

*
  •  25,850 25,850
  • Carnoustie, Scotland
    • View Profile
Re: Bridgeport Knee Mill Conversion?
« Reply #570 on: October 09, 2016, 02:30:46 PM »
I would imagine it would error if not correct.
Only thing with a VFD is you may travel slightly further than the commanded depth.

Offline Davek0974

*
  •  2,577 2,577
    • View Profile
    • DD Metal Products Ltd
Re: Bridgeport Knee Mill Conversion?
« Reply #571 on: October 10, 2016, 02:19:37 PM »
Well thats good news...

Seems to work just fine with the M84 macro :)

Tried various pitch and depths all the way up to 5mm pitch which is a bit steep :)

Couple of notes though - it needs a good headroom on Z above the start point as it overruns on the withdraw and will trip the soft limit again. Also at 300rpm it will overrun the reverse point by about 3mm on a 1.5mm pitch, just need to be aware of that :)

A little video...
https://youtu.be/ttz_LNAEEdA

It certainly tracks the rpm as i was gently applying the spindle brake while it was doing its thing and you can clearly see the Z drive belt changing speed with spindle speed :)

Also, the new DRO39 now shows real rpm - nice.

I played with the Mach pid loop again and although it did stabilise the speed at exactly the requested speed, it took a while to do so, i'll leave that off i think.

So, what sort of tap holder do i need to look for - floating, fully rigid??
Bridgeport Mill, Mach3 V062, CSMIO-IP/A controller, AC Servo Drives

Offline Hood

*
  •  25,850 25,850
  • Carnoustie, Scotland
    • View Profile
Re: Bridgeport Knee Mill Conversion?
« Reply #572 on: October 10, 2016, 02:48:05 PM »
ER collet holder does fine for rigid tapping, no need for a floating.

No overrun with a servo spindle or even if you could utilise +/-10v with a VFD and tune via the plugins PID. With the open loop VFD then you will get the overrun.

Hood

Offline Davek0974

*
  •  2,577 2,577
    • View Profile
    • DD Metal Products Ltd
Re: Bridgeport Knee Mill Conversion?
« Reply #573 on: October 10, 2016, 03:10:35 PM »
Pretty certain the vfd only supports 0-10v plus fwd/rev signals and not +/-10v so cant use the CSMIO servo DAC output or pid.

Not to worry, i think it will do fine, just need to assess the overrun before diving into a job and make allowance.

:)
Bridgeport Mill, Mach3 V062, CSMIO-IP/A controller, AC Servo Drives

Offline Hood

*
  •  25,850 25,850
  • Carnoustie, Scotland
    • View Profile
Re: Bridgeport Knee Mill Conversion?
« Reply #574 on: October 10, 2016, 04:59:11 PM »
Just call it short, run it and see how deep it goes then alter the depth and run again if it wasn't deep enough.

Offline Davek0974

*
  •  2,577 2,577
    • View Profile
    • DD Metal Products Ltd
Re: Bridgeport Knee Mill Conversion?
« Reply #575 on: October 15, 2016, 07:19:39 AM »
Was recently asked for some videos, here we go...

Rigid tapping...
https://youtu.be/1UOak0qTHsY

Full machine conversion walk-around...
https://youtu.be/utjrP_94KIk

:)
Bridgeport Mill, Mach3 V062, CSMIO-IP/A controller, AC Servo Drives

Offline Hood

*
  •  25,850 25,850
  • Carnoustie, Scotland
    • View Profile
Re: Bridgeport Knee Mill Conversion?
« Reply #576 on: October 15, 2016, 02:34:04 PM »
Looks to be working well :)
I can see all spare pieces of metal in your workshop will soon have tapped holes in them :D


Hood

Offline Davek0974

*
  •  2,577 2,577
    • View Profile
    • DD Metal Products Ltd
Re: Bridgeport Knee Mill Conversion?
« Reply #577 on: October 15, 2016, 02:45:08 PM »
LOL

Already found a use for a bunch of aluminium offcuts - the support bracket to hold the auxiliary spindle when not in use. Will be mounted up where the lifting eye goes on the top of the ram.

Designing it now in fusion - loads of tapped holes, chamfers, multiple tool changes, facing, boring, counter-boring the works :)
Bridgeport Mill, Mach3 V062, CSMIO-IP/A controller, AC Servo Drives

Offline Davek0974

*
  •  2,577 2,577
    • View Profile
    • DD Metal Products Ltd
Re: Bridgeport Knee Mill Conversion?
« Reply #578 on: October 16, 2016, 08:04:25 AM »
Here we go, nice fun little project for a Sunday morning....

Fits perfectly, works well and used loads of tool changes :)
Bridgeport Mill, Mach3 V062, CSMIO-IP/A controller, AC Servo Drives

Offline Hood

*
  •  25,850 25,850
  • Carnoustie, Scotland
    • View Profile
Re: Bridgeport Knee Mill Conversion?
« Reply #579 on: October 16, 2016, 09:26:56 AM »
Nice :)