Hello Guest it is March 29, 2024, 02:16:04 AM

Author Topic: Bridgeport Knee Mill Conversion?  (Read 270424 times)

0 Members and 2 Guests are viewing this topic.

Offline Davek0974

*
  •  2,606 2,606
    • View Profile
Re: Bridgeport Knee Mill Conversion?
« Reply #750 on: March 31, 2018, 10:38:50 AM »
Ok, so i finally got i all bolted up and the new drawbar made, mounted on the mill and, well clearly I still have work to do :(

The idea of allowing the wrench to fall will not work as the mechanism is not slack enough to let it - ok so we go to plan B and use air to push it - this works ok.

Next, the idea of not starting the impact until the Torx bits mate will not work - the Torx bits jam instead of mating about 75% of the time, might be able to improve this a bit by grinding the profiles a bit, will save that for later.

Next, with the wrench being held down, you cant easily insert a tool as it needs to push the drawbar upwards, but the cylinder is pressing it down so it risks cross-threading etc.

So I guess you MUST release the wrench after the tool is released? - I have no idea of the cycle here, all the videos just show it working, no real detail.

Does anyone know what i am missing here - anyone actually built a power drawbar for a threaded tool holding system like BT30??

Offline TPS

*
  •  2,501 2,501
    • View Profile
Re: Bridgeport Knee Mill Conversion?
« Reply #751 on: April 01, 2018, 08:20:45 AM »
what would be to use a hex bolt insteed of torx,
in combination with a long nut it would allow the
screw to go into the nut without any pressure on
the screw.

just thinking.

Thomas
anything is possible, just try to do it.
if you find some mistakes, in my bad bavarian english,they are yours.

Offline Davek0974

*
  •  2,606 2,606
    • View Profile
Re: Bridgeport Knee Mill Conversion?
« Reply #752 on: April 01, 2018, 08:31:06 AM »
Thanks, I have made some progress now,

I had too much control of the wrench - removing the bottom bar has allowed it to move easily now.

The Torx has better torque rating than hex - I have modified the head a bit with the grinder and that has allowed it to mate easier now.

I am trying to find my PLC software disc so i can set up a simple control logic to get it cycling, its here somewhere.........

Offline TPS

*
  •  2,501 2,501
    • View Profile
Re: Bridgeport Knee Mill Conversion?
« Reply #753 on: April 01, 2018, 08:40:34 AM »
why using an external plc and not the cslab ?
anything is possible, just try to do it.
if you find some mistakes, in my bad bavarian english,they are yours.

Offline Davek0974

*
  •  2,606 2,606
    • View Profile
Re: Bridgeport Knee Mill Conversion?
« Reply #754 on: April 01, 2018, 08:49:38 AM »
easier to mess about with until I know exactly what i want, thats all.

not good messing about in the cab i think, also easy to put it all to one side if i need to run the mill.

Offline TPS

*
  •  2,501 2,501
    • View Profile
Re: Bridgeport Knee Mill Conversion?
« Reply #755 on: April 01, 2018, 09:02:31 AM »
i mean a outside hex screw with Long nut.
this would the screw allow to go up when you
insert new tool and you don't have to lift the wrench.
anything is possible, just try to do it.
if you find some mistakes, in my bad bavarian english,they are yours.

Offline Davek0974

*
  •  2,606 2,606
    • View Profile
Re: Bridgeport Knee Mill Conversion?
« Reply #756 on: April 01, 2018, 09:13:35 AM »
Nice, thanks

I'll note that if we get to Mk2 ;)

Offline Davek0974

*
  •  2,606 2,606
    • View Profile
Re: Bridgeport Knee Mill Conversion?
« Reply #757 on: April 21, 2018, 09:13:45 AM »
Ok so the project is still going on :)

I now have a custom screenset, probe, probing macro's etc all working well.

Today I was bothered by some odd vibration I had since fitting the BT30 spindle, here's a short video of the top...

https://youtu.be/MJAr941aL-U

So I blamed the DIY drawbar, made another one, just as bad?

Tipped the head over and had a look and the splined portion of the spindle is clearly bent :(

https://youtu.be/jEhYINbUgzI

The tool section runs very true so not sure how you bugger a spindle like this??

It was like it when i got as i have had no crashes.

Now, not sure what to do really, it took ages to find that spindle, they are not that common. I have sold all my R8 tooling and only have BT30 now.

Can they be straightened?

I could push it out in the garden and torch it - it seems every time i get ahead she kicks me in the 'nads :(

Any ideas?
Re: Bridgeport Knee Mill Conversion?
« Reply #758 on: April 21, 2018, 10:15:46 AM »
Take you time and straighten it while you look for a better spindle.

Mike.
We never have the time or money to do it right the first time, but we somehow manage to do it twice and then spend the money to get it right.

Offline Davek0974

*
  •  2,606 2,606
    • View Profile
Re: Bridgeport Knee Mill Conversion?
« Reply #759 on: April 21, 2018, 12:28:29 PM »
Need to find an approved method first, I don't have much in the way of surface plates etc, do have a 20T press though.

Certainly a PITA though.

QC30 spindles are very rare and it cost a lot too.