Messages

931

General Mach Discussion / Re: Hybrid stepper motors from e bay

« on: November 03, 2016, 07:40:34 AM »

So you heavenly one end connected to ground but that point is at the plug/socket?
It should be ok like that, motor cables do not even need to be shielded really - they are higher voltage and current connections which are generally immune to interference and also emit very little as well, i don't think that area is your problem.

Has it always been dodgy/losing steps or is this new behaviour?

Even messy wiring can work, its not ideal but I have seen a complete rats nest of unshielded wiring in a commercial plasma table controller that even shocked me, and they were being sold like that!

932

General Mach Discussion / Re: Hybrid stepper motors from e bay

« on: November 03, 2016, 06:52:14 AM »

Personally, if it was working ok and is now losing steps and you have not altered wiring then I would not look at wiring apart from checking for loose connections.

Wiring would not suddenly go bad

Of course, if it has always been dodgy and lost steps then by all means modify. tidy, correct  the wiring.

Unless its a plasma cutter I would not look at grounding rods.

The plugs should be ok as long as you have not created ground loops by connecting both ends of the shielding to ground

933

General Mach Discussion / Re: Backlash...

« on: November 03, 2016, 06:23:03 AM »

I like pushing the envelope

It seems to work ok so I can't see any harm in it, if it was too bad I would expect broken tools but this one seems fine after running these tests and it wasn't new when i started.

I know it's not an engraving machine as such, but it does seem to function pretty well as one, I don't do much engraving luckily but needed to know if it was possible and it seems so.

I still have the mini-mill but really need to sell that on now to recover space in the shop as well as cash.

I think she will do just fine but being me I like to know exactly what limitations i have

Just for completeness, the "test" is pictured below, the T is about 18mm tall, this picture was taken before i fitted the new thrust bearings on X & Y, its even better now.

934

General Mach Discussion / Re: Backlash...

« on: November 02, 2016, 03:44:58 PM »

Did some V-Carve tests tonight, 28000 lines, 38mins run time, it will run with BC on but sounds happier with it off, physical results look the same.

Will do some proper mill cuts ASAP.

935

General Mach Discussion / Re: Hybrid stepper motors from e bay

« on: November 02, 2016, 01:00:23 PM »

Ha, that was an autocorrect typo - it should say strain

936

General Mach Discussion / Re: Hybrid stepper motors from e bay

« on: November 02, 2016, 11:53:17 AM »

You have a slave axis - do you have homing switches and does it straighten the slave axis upon hoping?

Just wondering if that axis has become twisted somehow - this will put staring on the motors and bearings etc.

937

General Mach Discussion / Re: Hybrid stepper motors from e bay

« on: November 02, 2016, 11:05:28 AM »

Separate drives is good, may be worth trying another bob but first i would swap motor connections and see if the fault follows the cable(faulty drive) or stays with the motor(faulty motor)

If all axes are messing about it may even be PSU or the BOB or more.

938

General Mach Discussion / Re: Hybrid stepper motors from e bay

« on: November 02, 2016, 10:30:36 AM »

Assuming they are carbide cutters, I would run a 6mm 2 flute end mill in aluminium at 24,000rpm, 1500mm/min 2mm deep and slotting or full-width cut. In hard wood something like 4000mm/min.

But you must clear the chips so air blast at a minimum really.

If your figures used to work and have now stopped, something is not right - maybe a seized bearing or linear guide?

It may be a failing drive - is it one or both axes that lose steps?

If one it may be possible to swap the connections to verify if the motor is failing or the drive is failing.

Is this an all-in-one drive board - all three axes on one board, I have not heard many good stories about them. Most builds and upgrades go for separate drives running from a breakout board.

939

General Mach Discussion / Re: Hybrid stepper motors from e bay

« on: November 02, 2016, 09:08:31 AM »

Do not increase steps per in an attempt to fix - these figures once set will not change as they are hardware related.

Let me know what size and type of tool you are running and i can give a rough speed / feed for you, also spindle power, type etc

940

General Mach Discussion / Re: Backlash...

« on: November 02, 2016, 05:51:14 AM »

Thats probably why it sounds so rough, I think i'll leave it off and do some accuracy tests, I may be chasing ghosts here.

V-Carve G-Code is evil, probably the nastiest code possible as it is thousands of minute moves in all axes all at once.