using iES-1706 (Nema 17 85 oz-in/0.6 N.m) with Duet

What do you think about using iES-1706 [www.americanmotiontech.com] whith the duet?

I actually have 0.9 nema 17 0.44 N.m steppers with 24V PSU and I loose steps when I go faster than 80mm/s with motor current at 1.5 A on 1.68 steppers



Thanks in advance

Looks interesting, but expensive.

I don't understand the issue you are having with your existing motors. I use motors with a very similar specification on my delta, and it achieves speeds of 300mm/sec using 1A current. What sort of printer do you have, and what is the steps/mm? Perhaps you have the acceleration set too high?

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Closed loop steppers for a printer is something extremely rare. This is something desirable for a router, but the loads on a printer are fairly low and with good parameters, you may never loose a step.

I also use 0.9 ° steppers with 0.44 N.m steppers on the enclosed delta 'DBox', supplied in 24V
The only moment where I loosed steps was while brushing my hotend, because that was outside 'normal' area, so with a very high carriage speed and acceleration. Reducing speed proofed unsufficient, I had to also reduce the acceleration (temporarily).
For use within the printable diameter, I never had any trouble and my current is adjusted to 1.2A for 1.68A steppers, so I have margin.
My standard acceleration is now 6000, while I had run for some time at 8000 (3000 in Z).

There is an important parameter for 0.9° steppers, you shall reduce the maximum instant speed change, as a 0.9° stepper cannot instantly accelerate as much as an 1.8° steppers, especially if your machine is stiff or heavy.
I had noticeable differences when I changed my arms, as the new ones were much more stiff.
My parameter for instant speed change on D-Box (or Lily-Big) is

M566 X1200 Y1200 Z800 E500:500

Note that the reduced Z instant speed change compared to X/Y was to stop my effector from jumping in its supports at every layer change.

edit: Please note that my delta arm minimum angles are 22°, a bit higher than the average delta, which reduce maximum accelerations and speed at maximum printable diameter.

reprap.org/wiki/Choosing_stepper_for_a_delta [reprap.org]

Edited 3 time(s). Last edit at 09/02/2016 08:20AM by PRZ.

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Pierre

- Safety [reprap.org]
- Embedded help system for Duet and RepRap Firmware [forums.reprap.org]
- Enclosed delta printers Lily [rouzeau.net] and Lily Big [rouzeau.net]
- OpenScad delta printer simulator [github.com]
- 3D printing on my site [www.rouzeau.net]

My printer is 1500mm high, 600 mm wide, 500mm diagonal rods and a bed of 265mm (i'm building a 400mm bed)

The diagonal rods are 8mm square and 6mm ID (glued with a 75mm 6OD and 4ID round carbon fiber ) it has robotdigg plates (very heavy) and openbuild carriages


and these are my printer's parameters:

M665 R255.5 L504.48 B132.5 H580.28 X0 Y0 Z0
M92 X160 Y160 Z160 ; Set axis steps/mm
M906 X1500 Y1500 Z1500 E900:900:900:900:900:900 I50 ; Set motor currents (mA); set each extruder explicitly
M201 X1000 Y1000 Z1000 E1500 ; Accelerations (mm/s^2)
M203 X7000 Y7000 Z7000 E3600 ; Maximum speeds (mm/min)
M566 X600 Y600 Z600 E1200 ; Maximum instant speed changes

This is a relatively large machine, with weights on the heavy side, but your parameters looks workable, accelerations and speed being quite low.
What is the weight of one arm ?

You have 20 teeth pulleys, using 16 teeth may help a bit. For that printer size, larger belts (9mm) may increase stiffness.
You cannot increase much the current, you are at the reasonnable maximum both on the stepper and board (assumed to be 0.8.5). [Edit]: Your board shall have good forced cooling at this current.

Your arms length are ok, for 400mm diameter, you will have ~26° minimum angle, which is quite good, but as you have now a smaller bed diameter, you are working now in very favorable conditions. If you loose steps now, that will be worse at larger diameter.

While this is a large machine, overall this should work. Before changing steppers, you shall check everything, including all wiring.
Did you identify the phases where you loose steps ?
Maybe search if you have mechanical resonances ? Did you have dampeners on your steppers ?

AussiePhil have used Nema23 on Duet 0.8.5 with a larger machine, but that is really more than the board was designed for and you may get mid-band resonances.

Edited 1 time(s). Last edit at 09/02/2016 06:10PM by PRZ.

---

Pierre

- Safety [reprap.org]
- Embedded help system for Duet and RepRap Firmware [forums.reprap.org]
- Enclosed delta printers Lily [rouzeau.net] and Lily Big [rouzeau.net]
- OpenScad delta printer simulator [github.com]
- 3D printing on my site [www.rouzeau.net]

Each arm weights 37 grams (222 grams total) the OpenBuild Carriages are heavy.

I have 20 teeth pulleys. I'll buy 16 teeth to see if works better.
I have 6 mm belts (unfortunately I can't get 9mm belts in my country )
I have Duet 0.8.5 V. Firmware Version: 1.15b (2016-08-25) and Web Interface Version: 1.12



> Did you identify the phases where you loose steps ?
No, and I attach a photo to see if you can help me with these.

> Maybe search if you have mechanical resonances ?
I don't hear any strange noise while the printer is running

> Did you have dampeners on your steppers ?
No, I don't have dampeners.

I think it looses steps in the 3 motors at once because remains in the same plane after the error. that's strange

So, what you have is shifting layers?
Have a look to this page : [forums.matterhackers.com]
This thread is also interesting, even if I think your problem is different : [forums.reprap.org]

Considering the size of your printer, you may have the belt jumping on teeth.
Your belt shall be well tensioned. But not too much. Excessive tension can also cause step loss. Check if the belt is not rubbing on pulley flanges and that your stepper is well perpendicular.
Also check your pulleys are well tightened on shaft. This is a common problem.
Another possibility is that driver overheat. You may try to reduce the current to 1400.

---

Pierre

- Safety [reprap.org]
- Embedded help system for Duet and RepRap Firmware [forums.reprap.org]
- Enclosed delta printers Lily [rouzeau.net] and Lily Big [rouzeau.net]
- OpenScad delta printer simulator [github.com]
- 3D printing on my site [www.rouzeau.net]

I consider myself to be a noob, but what I see looks more like a layershift to me...
Although this shift is rather huge, I might say...

Edited 1 time(s). Last edit at 09/03/2016 02:32PM by Teilchen.

Quote
PRZ
So, what you have is shifting layers?
Have a look to this page : [forums.matterhackers.com]
This thread is also interesting, even if I think your problem is different : [forums.reprap.org]

Considering the size of your printer, you may have the belt jumping on teeth.
Your belt shall be well tensioned. But not too much. Excessive tension can also cause step loss. Check if the belt is not rubbing on pulley flanges and that your stepper is well perpendicular.
Also check your pulleys are well tightened on shaft. This is a common problem.
Another possibility is that driver overheat. You may try to reduce the current to 1400.

I'll try to reduce current to see what happens. Thanks!

Quote
demonio669

Quote
PRZ
So, what you have is shifting layers?
Have a look to this page : [forums.matterhackers.com]
This thread is also interesting, even if I think your problem is different : [forums.reprap.org]

Considering the size of your printer, you may have the belt jumping on teeth.
Your belt shall be well tensioned. But not too much. Excessive tension can also cause step loss. Check if the belt is not rubbing on pulley flanges and that your stepper is well perpendicular.
Also check your pulleys are well tightened on shaft. This is a common problem.
Another possibility is that driver overheat. You may try to reduce the current to 1400.

I'll try to reduce current to see what happens. Thanks!

I reduce the current to 1000ma and the steppers don't loose steps.

Can it be some kind of heat protection that cuts the current to the 3 steppers and it produces the layer shift ?

Yes, there is thermal shutdown in the drivers. The recovery can be quite fast (say, a fraction of a second), so this can cause intermittent working and that is difficult to diagnose. But you don't have loss on three steppers, probably only one. Shifting occur when you loose step on one column only.

You could do much more than 1000 mA, and considering the size of your machine 1350 to 1400 mA might be a better choice.
With your parameters forced cooling is not an option and shall be cautiously designed.
You need appropriate forced cooling, which cool the underside of the board as much as the top.
I've run up to 1400 mA on movement with the extruder driver at 1500, but my board is installed vertically and on 15mm columns to have good airflow on both faces. The ideal shall be to have airflow guides. I reduced current on movement since, as I somewhat reduced the acceleration to lower mechanical stress.

Edited 2 time(s). Last edit at 09/04/2016 09:37PM by PRZ.

---

Pierre

- Safety [reprap.org]
- Embedded help system for Duet and RepRap Firmware [forums.reprap.org]
- Enclosed delta printers Lily [rouzeau.net] and Lily Big [rouzeau.net]
- OpenScad delta printer simulator [github.com]
- 3D printing on my site [www.rouzeau.net]

Quote
PRZ
Yes, there is thermal shutdown in the drivers. The recovery can be quite fast (say, a fraction of a second), so this can cause intermittent working and that is difficult to diagnose. But you don't have loss on three steppers, probably only one. Shifting occur when you loose step on one column only.

You could do much more than 1000 mA, and considering the size of your machine 1350 to 1400 mA might be a better choice.
With your parameters forced cooling is not an option and shall be cautiously designed.
You need appropriate forced cooling, which cool the underside of the board as much as the top.
I've run up to 1400 mA on movement with the extruder driver at 1500, but my board is installed vertically and on 15mm columns to have good airflow on both faces. The ideal shall be to have airflow guides. I reduced current on movement since, as I somewhat reduced the acceleration to lower mechanical stress.

Thank You! I set the current to 1350 and the speed and accelerations to:

M201 X3000 Y3000 Z3000 E3500 ; Accelerations (mm/s^2)
M203 X15000 Y15000 Z15000 E4000 ; Maximum speeds (mm/min)
M566 X1200 Y1200 Z800 E800 ; Maximum instant speed changes



Without loosing any steps in a 16hs print!!!


Thank You to all!!


But... i'm still interested in iES-1706 stepers. I think that in combination of a dual e3d volcano hotend I can go faster than today.
I think would be nice to see encoder support in firmware to check the steppers status .

But now, my printer is faster and don't loose steps

If you want closed loop cheap.

[www.ustepper.com]

[www.youtube.com]

or
[www.jmc-driver.com]

I use these iHSS57-36-20 on my cnc mill for $70 a piece but they are nema 23, it looks like they added a iHSV42 line which would be nema 17 and prices are incredible compared to anything else I found. You do have to buy direct and deal with all the import crap but it was worth it.

I am going to work on getting these working on a delta with the new Duet wifi in a couple of week. Tried to use these ran from the expansion header on a 0.85 but I ran out of time.

The usteppers are not just a closed loop stepper drive they a mini arduino board that could be programed for axis synchronization between ustepper boards so even the extruder would stop until all axis returned to the correct position, but I do not have the programing skill to do this.

Edited 5 time(s). Last edit at 09/08/2016 10:27AM by jmjcoke@gmail.com.

Nice project the ustepper!
I'm also following this project: [tropical-labs.com]