Slide lubricant, bad alignment or not enough torque ?

[Robinwales]

The Story
I've inherited an old German aluminium Haase machine from my late father.
It appears to be the smaller version of this machine if you Google "Haase Cut 2000 Professional CNC mill and engraving machine "
The original controller was not working so removed it and replaced it with TB6560, Arduino, 24v power supply and using the existing steppers.
Got it moving but the thing struggled with skipping steps and that was using a drag knife on vinyl.

Bigger is Better, right ?
Bought some new steppers 23HS9442, DM542A drivers and a 36v supply from Longs hoping that this would fix the skipping steps problem. Got it all rigged up with Arduino and the damn thing still skips.
It's like the linear rails don't slide easily enough. They don't appear to have any ball bearings so it's just like metal on metal tube with grub screws for adjustment. I've tried silicone spray to lubricate them before use and adjusted the grub screws but no joy.

Am I missing something obvious ?
Thanks
Rob

[Robinwales]

[Robin Hewitt]

Silicon spray can cause galling at a metal to metal sliding contact. It is famous for destroying air guns. While you clean it out you can investigate the problem.

Can you feel excessive drag when you wind the slide screws by hand?

Are you blessed with an oscilloscope? You could check out the Arduino step pulse. Is it excessively up or down? A square wave is perfect.

You can get small amounts of slideway oil, no need to get the whole 5 litres.

[dazp1976]

[

Bigger is Better, right ?
Rob

Nope. Only with the right voltage.
However, if you can't get up to at least 1000mm/min with it then something is definately wrong.
What speed are you trying to run it at as a matter of interest?.

[Cube3]

Is that some sort of IGUS bearing (sleeve) I see? It may be a replacement wear part or you my be able to find a IGUS bearing to fit.

Moving the slide without the ball screws should tell you quite a bit.

Gut feeling, with those steppers it's not the slides!

Sent from my SM-A715F using Tapatalk

[dazp1976]

Silicon spray can cause galling at a metal to metal sliding contact. It is famous for destroying air guns.
You can get small amounts of slideway oil, no need to get the whole 5 litres.

GT85 Teflon spray all day long for cleaning metal to metal surface slides.
I used to run automated equipment from Heidelberg machinery and they weren't wrong on that one.

Silicon spray! ..... Noooooo!!.

[dazp1976]

Is that some sort of IGUS bearing (sleeve) I see? It may be a replacement wear part or you my be able to find a IGUS bearing to fit.
Moving the slide without the ball screws should tell you quite a bit.
Gut feeling, with those steppers it's not the slides!
Sent from my SM-A715F using Tapatalk

With the inductance on those steppers, they need DM860 drives and minimum 60v to get decent high rapid speeds.
Proven.
But, never any issue on 36v running at 300rpm with 5mm pitch ballscrews, and my gibs were tight as (mill).

[Robinwales]

Silicon spray can cause galling at a metal to metal sliding contact. It is famous for destroying air guns. While you clean it out you can investigate the problem.

Can you feel excessive drag when you wind the slide screws by hand?

Are you blessed with an oscilloscope? You could check out the Arduino step pulse. Is it excessively up or down? A square wave is perfect.

You can get small amounts of slideway oil, no need to get the whole 5 litres.

Unfortunately, don't have an oscilloscope.
When turned by hand not sure I recognise any excessive drag, although I have nothing to compare it with. I've disconnected the threaded rod and tried sliding the carriages by hand and there is some metal to metal suction to get them moving. It's not possible to push them with your fingers and for them to slide from one end to the other, if you know what I mean.
Will try some slideway oil.
Thanks

[Robinwales]

Nope. Only with the right voltage.
However, if you can't get up to at least 1000mm/min with it then something is definately wrong.
What speed are you trying to run it at as a matter of interest?.

I would be happy with 1000mm
Would like to carve some beech and cut some birch plywood
Not really bothered by the speed, would just like it to be automated
Thanks

[Robinwales]

GT85 Teflon spray all day long for cleaning metal to metal surface slides.
I used to run automated equipment from Heidelberg machinery and they weren't wrong on that one.

Silicon spray! ..... Noooooo!!.

Aldi seem to do this spray will give it a try
Thanks