Hello Guest it is March 18, 2024, 10:15:28 PM

Author Topic: Bridgeport Knee Mill Conversion?  (Read 269084 times)

0 Members and 2 Guests are viewing this topic.

Offline Davek0974

*
  •  2,606 2,606
    • View Profile
Re: Bridgeport Knee Mill Conversion?
« Reply #400 on: August 23, 2016, 03:26:23 AM »
Yep, will head that way.

It's a bit like Homer Simpsons' Smoke alarm that goes off all the time to let you know there is no smoke ;)

Will dig a timer out of the junk box.

Offline Davek0974

*
  •  2,606 2,606
    • View Profile
Re: Bridgeport Knee Mill Conversion?
« Reply #401 on: August 28, 2016, 07:17:45 AM »
Cut some button labels today, also had the console powder-coated :)

Still waiting on some knobs for FRO & SPO

Offline Hood

*
  •  25,835 25,835
  • Carnoustie, Scotland
    • View Profile
Re: Bridgeport Knee Mill Conversion?
« Reply #402 on: August 28, 2016, 11:18:02 AM »
Powder coating looks great :)

Hood

Offline Davek0974

*
  •  2,606 2,606
    • View Profile
Re: Bridgeport Knee Mill Conversion?
« Reply #403 on: August 28, 2016, 01:29:15 PM »
Yep, its a local place, does a damn fine job.

Offline Davek0974

*
  •  2,606 2,606
    • View Profile
Re: Bridgeport Knee Mill Conversion?
« Reply #404 on: September 01, 2016, 01:25:38 PM »
Got the panel finished, just need to find or make some 22mm blanking plugs :)

I found tonight the limitations of a poor Z axis travel, did a test run on the parts that been discussed in my thread on work in different quadrants.

Ok so maybe i am being a bit overzealous by asking for a 35mm clearance plane, not sure, but when you take out the clearance plane, thickness of material, a little more for drill breakthrough, you are left with a  very small window of tool-height variation before the CSMIO throws a soft-limit-switch and bums out.

It needs the z axis to be zeroed when it's 36mm down from top limit - that allows the code to send it to Z35 for clearance, then you have to make sure that the shortest tool does not run it out of Z axis travel - i was going to use a slightly longer drill but will have to bum that idea and mill the holes or get stub-length drills etc.

It really is a lot more limiting than i imagined it would be, not having the ability to just throw the knee down a few turns to fit a big drill is an example - this would bugger the Z zero setting.

I guess i will have to run with much smaller clearance plane and double-check before each run that it misses the clamps etc.

Now i see why they make VMC's with 300+mm of Z axis travel :(

Offline Hood

*
  •  25,835 25,835
  • Carnoustie, Scotland
    • View Profile
Re: Bridgeport Knee Mill Conversion?
« Reply #405 on: September 01, 2016, 05:41:51 PM »
You will always run into a machine being too small, whether it is a lathe or a mill or a plasma or whatever.
Here is my Chiron doing the wedge holes on the lathe turret I made, 35 seconds in and you see how close the drill is at full height on Z, only 0.2mm clearance :D
https://www.youtube.com/watch?v=MUkyRjqGGow

Hood

Offline Davek0974

*
  •  2,606 2,606
    • View Profile
Re: Bridgeport Knee Mill Conversion?
« Reply #406 on: September 02, 2016, 01:43:16 AM »
I've said it before, but man, i love that basket tool-changer :)

Yep that was close on the drill. I think part my problem is still thinking manually, not CNC, you have to replace your brain with code and know what will happen before you press the green button.

In your case i would have dropped the knee and done two setups maybe but thats just a thought ;)

I can lower the clearance plane to miss clamps - even my generous 35mm would not miss the bolt/studs so maybe i was just going too far and using up z travel for no gain, 20mm will skip a clamp.

So much to learn.

I guess one test would be to park at clearance height and make sure the shortest tool for the job can reach the lowest point in the job and longest tool clears the work, if it passes that then it should run.

Offline Hood

*
  •  25,835 25,835
  • Carnoustie, Scotland
    • View Profile
Re: Bridgeport Knee Mill Conversion?
« Reply #407 on: September 02, 2016, 01:50:30 AM »
In your case i would have dropped the knee and done two setups maybe but thats just a thought ;)

You would struggle to do that on the Chiron, table fixed solid and never moves :D
Hood

Offline Davek0974

*
  •  2,606 2,606
    • View Profile
Re: Bridgeport Knee Mill Conversion?
« Reply #408 on: September 02, 2016, 02:20:53 AM »
:)

The idea of using the knee to do tool offsets is pretty cool but moving the knee is not usually as accurate on a BP, i guess a direct feedback from a glass scale encoder would sort that but we're heading into exotic territory here ;)

I just have to increase my knowledge i think.

Offline Hood

*
  •  25,835 25,835
  • Carnoustie, Scotland
    • View Profile
Re: Bridgeport Knee Mill Conversion?
« Reply #409 on: September 02, 2016, 03:27:22 AM »
Was always planning on doing the knee of the Beaver NC5 for use with tool offsets. Ray Livingston did that if I recall, should work well and as the Beaver already had a motor on the knee it wouldnt have been a huge job to swap.
 Not sure why you think the knee would be less accurate, as long as the gib was snuggled up then it would be just as good as the quill, in fact lots of people choose to do the knee rather than the quill, just it requires a much bigger motor and is often a lot slower.


Maybe  having a scale on the knee and cranking it manually and using a fixture offset for things such as drills would work, that way you could position manually with accuracy and then change the work offset to allow for the change in the height.

Hood