Electronic Lead Screw Project

[Phil GrantParticipant @philgrant54580]

Hi,

I've had my stepper mounted end on to the leadscrew but always wanted to have it at right angles but didn't want to spend the cash on a proper gearbox so I've been playing around with the idea of my own mount.

I ordered some "Mitre / Bevel" Gears from China for about £3 and did a design in F360 with the idea of 3D printing them, yes I know that the 3D printed parts may not be up to it but it's not going to cost me a lot to try it out.

Anyway i've got the first off prototypes printed and now just checking for fit. Here are some pictures just incase it sparks any ideas …. Still very much a work in progrgess though.

[Brian OldfordParticipant @brianoldford70365]

Posted by Phil Grant on 28/05/2020 09:12:35:

Hi,

I've had my stepper mounted end on to the leadscrew but always wanted to have it at right angles but didn't want to spend the cash on a proper gearbox so I've been playing around with the idea of my own mount.

I ordered some "Mitre / Bevel" Gears from China for about £3 and did a design in F360 with the idea of 3D printing them, yes I know that the 3D printed parts may not be up to it but it's not going to cost me a lot to try it out.

Anyway i've got the first off prototypes printed and now just checking for fit. Here are some pictures just incase it sparks any ideas …. Still very much a work in progrgess though.

Hi Phil.

Are you intending for the bevel gears to be enclosed within the casing?

Domestic chores are slowing progress but I'm drifting off the skew gears idea as I'm pretty certain the stepper motor bearings aren't too keen on the end thrust. My next iteration may contain bevel gears if I can squeeze it all in the limited space.
I'll also hope to be fitting my twist of the lead-screw thrust bearing.
Wish me luck.

[Phil GrantParticipant @philgrant54580]

Are you intending for the bevel gears to be enclosed within the casing?

Domestic chores are slowing progress but I'm drifting off the skew gears idea as I'm pretty certain the stepper motor bearings aren't too keen on the end thrust. My next iteration may contain bevel gears if I can squeeze it all in the limited space.
I'll also hope to be fitting my twist of the lead-screw thrust bearing.
Wish me luck.

Yes the gears are enclosed apart from the end which I plan to cover with a piece of perspex. The inner sleeve is fixed to the lathe bracket but the outer clamp slides around allowing for a variable mounting angle to clear the bits on the lathe.

Ofcourse, good luck with your twisting.

[Phil GrantParticipant @philgrant54580]

Brian,

Pictures as requested

[Brian OldfordParticipant @brianoldford70365]

Many thanks Phil. I do like the control panel. £?

[dcostaParticipant @dcosta]

Hello,
Resuming this project, I verified that the synchronization between the rotary encoder and the stepper motor was not correct.
The rotary encoder (B E6B2 – CWZ6C) has a resolution of 1000P / R.
The motor stepper completes a rotation in 200 steps (1.8º per step) and the DM542 driver is configured in DIP switches for 8 microsteps (1600 Steps / Rev).

In the Configuration.h file, following Clough, i have
#define ENCODER_RESOLUTION 4000

#define STEPPER_MICROSTEPS 8
#define STEPPER_RESOLUTION 200

But, if I change the STEPPER_MICROSTEPS variable to 12, and test 40 rotations on the rotary encoder, the synchronization with the motor remains correct.

Although the sync remains correct, it seems to me that there is something wrong with this configuration.
Any opinions are welcome.

greetings from
Dias Costa

[Brian OldfordParticipant @brianoldford70365]

After being diverted onto other tasks (some from SWMBO and others such as collecting an alternative mill) and having a long ponder on the problem of stepper motors not taking too kindly to the end thrust from skew gears and following the advice of others I decided to replace the previous arrangement with 2:1 Bevel Gears.That in itself proved to be a bit of a task because the larger bevel gear being attached to the lead-screw required modification to fit and to be able to drive.
I now need to cut a key-way through the 5/8" hole to enable the gear to transmit power to the lead-screw.

Time to fire up the shaper.

[Phil GrantParticipant @philgrant54580]

Nice solution, a bit more "meaty" than my approach, I may have overthought it maybe a angle bracket would suffice hmmm…

[Brian OldfordParticipant @brianoldford70365]

Phil

As you may notice I have a few more things to do before I get to try this arrangement to work.

1: I have the key-way to cut.

2: Arrange to secure the bevel-gear to the lead-screw. (The grub-screw holes are there to secure the original bevel gear to the sleeve that fits around the lead-screw.)

3. Insert the remaining two screws that fix the stepper motor to the angle bracket.

[Brian OldfordParticipant @brianoldford70365]

Courtesy of Phil Grant I now have my Clough42 ELS control box. One of those jobs you need three hands to assemble. 😁

I used M3 x 22 Csk black cap-heads to fix it together. 20 mm or even 16 mm might have served OK.

[Phil GrantParticipant @philgrant54580]

Looks good

[Roy VaughnParticipant @royvaughn26060]

For information of those who don't keep an eye on Github, James Clough has just made a new release of the software which addresses concerns about the effect of noise in the system leading to unsafe behaviour.

[Tony Pratt 1Participant @tonypratt1]

I have had the ELS running for a year now but just a heath Robinson lash up but rock solid in operation. When I installed all the bits in situ the problems started.

The keypad was mounted just above the tacho on my Warco WM290v & was basically unusable as it would flicker, cut out & reset constantly, disconnecting the tacho sorted most of that out but I am still getting random value changes with no button pushes.

I told James [clough42] about the issues & he has released new software plus suggesting other possible causes, we think the main problem is the long lead from the control panel to the control board picking up interference.

Finally just to say James in Idaho has given excellent support from afar, what a great guy!

Tony

[Roy VaughnParticipant @royvaughn26060]

Tony, I had exactly the same experience. Careful earthing and a screened cable to the control panel helped but I still needed software mods to eliminate the problem complete. I ended up doing more or less what James has now released. It's been running error-free for several months now. You'll have to give up the ability to change panel settings while the spindle is turning though!

Roy

[Tony Pratt 1Participant @tonypratt1]

Roy, thanks for your system update, at least I'm not alone! Not being able to change the panel settings shouldn't be a problem as I can vary the feed rate on my lathe mechanically i.e. 1:1, 2:1 or .5:1.

thanks,

Tony

[Alan Wood 4Participant @alanwood4]

I have just completed the ELS on my Myford S7.

I connected the control panel to the control box using approximately 2m of CAT5 unscreened cable. I noticed hand capacity effects when resting my hand on the control box leading to jitter of the display. I fitted a split ferrite inside the control panel box and one on the cabling inside the main electronics box. This cleared the problem without further mods and it has not shown any twitching since. RS sell these in pairs (#811-9109).

Note that I used a larger diecast box so there was room inside the control panel box. Users of the 'normal' box size will need to fit the ferrite on the cable external to the control box.

Article here

 

Alan

Edited By Alan Wood 4 on 09/10/2020 09:34:36

Edited By Alan Wood 4 on 09/10/2020 09:36:05

Edited By Alan Wood 4 on 09/10/2020 09:37:08

Edited By Alan Wood 4 on 09/10/2020 09:37:57

[Tony Pratt 1Participant @tonypratt1]

Hi Alan,

can you check your link please, it doesn't seem to work [for me]?

Tony

[Alan Wood 4Participant @alanwood4]

Hi Tony, not sure what was happening. I have deleted and re-done it and think it is now OK.

Alan

[Tony Pratt 1Participant @tonypratt1]

Alan, yes that's working now, I'm impressed with the wiring!! I shall be happy if mine just works.

Tony

[Alan Wood 4Participant @alanwood4]

Thanks Tony, old habits/methods die hard !

Alan

[simondavies3Participant @simondavies3]

If it helps anyone…I have modified the lid to make the electronics board integral with the lid itself and changed the attachment method to screws tapped into blind holes from the rear of the board, removing one set of bolts from the front.

On Thingiverse at: **LINK**

Simon

Edited By Simon0362 on 10/10/2020 13:42:39

[Tony Pratt 1Participant @tonypratt1]

Finally working with no blips!! I fitted the split ferrite collars as suggested but unfortunately no better, I then updated the code from git hub [well my son did] & it's now sorted with no random data changes from the control panel, I think Clough42 lowered the clock speed?

Tony

[Roy VaughnParticipant @royvaughn26060]

Tony, glad to hear that. Yes, James says he has lowered the clock speed on the SPI bus which presumably should help noise immunity but still the fact that noise could change the settings dramatically while the spindle was rotating remained. I was seeing the control panel settings being returned as all-1s, which causes the system to go into reverse and enter screw cutting (i.e. usually high pitch) mode. His mods, which prevent changes while the spindle is rotating and check that only one control panel button is pressed at a time, constitute the real protection.

Roy

[Tony Pratt 1Participant @tonypratt1]

Roy, even with the new code installed I can change modes with the spindle running so I am confused.

Tony

[Roy VaughnParticipant @royvaughn26060]

Oh, I must have misunderstood what he said in his description of the changes. I must have a look at his code. Roy

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