New Build - 'Audit' CNC - Lathe Attachment

[Chaz]

It's very difficult to explain what this is. I've just bought 2 of them. One larger than the other. This video shows the unit best ...



These were made by a company and sold under the brand 'Audit'. Effectively its a 2 Axis clamp on Slant Bed lathe attachment meant to fit onto some Triumph / Colchester lathes. The straddle the saddle and then can be moved as needed along the bed. The smaller one I have has 10 inches of Z travel, the larger is 20 inches. I don't know the X distance but its massive.

We believe they were made for the oil industry where threading of long pipes was common place and these were used for a lot of the work.

The engineering that's gone into these is spectacular. They originally ran DC motors with 4.5NM torque. So on the AC servos side, I'd need around 1.5KW for similar performance unless I start to mess with pulleys / gears.

On top of each is a 8 tool Duplomatic ATC.

The weight of each of these is substantial. Even the small one cant be lifted by hand and needs a crane to lift.

I'm hoping I can get this mounted on my Harrison M300 which is starting to show its age and has some wear on the bed / cross slide.

So ye, Acorn or Acorn 6 for feedback .... feels like a waste of 4 axis however ...

The existing DC motors have incremental encoders on them and that would have given the original controls (which stands 6 feet tall) its feedback / control mechanism.

[Chaz]

Just looking at board options. The tool turret has PNP proximities and also for the angular position feedback. I know with Acorn we cannot read PNP which is a pain and it either needs some trickery or an Eth1616 board.

I'm also concerned about the latency that I saw when I was trying to do my Emco 320, using the Eth1616 board where I was struggling to stop the turret spinning (locking pin engagement) as by the time I saw the bit change, it was too late to fire the pin.

Can Acorn 6 manage PNP directly?

[Chaz]

Just looking at board options. The tool turret has PNP proximities and also for the angular position feedback. I know with Acorn we cannot read PNP which is a pain and it either needs some trickery or an Eth1616 board.

I'm also concerned about the latency that I saw when I was trying to do my Emco 320, using the Eth1616 board where I was struggling to stop the turret spinning (locking pin engagement) as by the time I saw the bit change, it was too late to fire the pin.

Can Acorn 6 manage PNP directly?

Just checked the documentation, suggests that this is possible. Great.

[Muzzer]

You may have seen these before - but for the rest of us:

Interesting article on HSM site: https://bbs.homeshopmachinist.net/forum ... attachment

And one for sale up in Scotland. https://www.hibid.co.uk/Audit-CNC-Lathe-attachment/

[Chaz]

You may have seen these before - but for the rest of us:

Interesting article on HSM site: https://bbs.homeshopmachinist.net/forum ... attachment

And one for sale up in Scotland. https://www.hibid.co.uk/Audit-CNC-Lathe-attachment/

Thanks. I actually bought these from Kev who was asking, he ended up buying 2 and then kept them a while and never used them. I believe you might know him?

The other one I saw too, thanks.