Switched from CW1 to CW2 an have a weird issue.

[ken226]

Maybe someone here has had this in the past, or knows what i should be looking for.

 

So, I switched from a CW1 that had the moons MS17HD7P408A-01 Nema 17 motor.  The new Stealthburner CW2 has this LDO-36STH20-1004AHG(XH) motor. 

 

I've complete the install and am currently doing a test print,  which seems to be going very well.  The part looks great, so far.

 

The issue I had while tuning it was that it was feeding filament too fast, and too much. Like, by a factor of 10x.   When I asked for 50mm,  It would try to ram 500mm through in just a few seconds and stalled the motor.    I reduced the lengths and speeds to 2mm and 1mm/s and was able to figure out that asking for 2mm was getting me 20mm,  and at about 10mm/second.

 

After some tuning, I was able to get the extruder to give me the correct amount and the correct speed, but to get there I ended up with a rotation distance of 223.236.  That seems absurdly high, since with my CW1 and the moons motor the rotation distance was like 22.6.

Here is the motor i'm using on the new CW2:

LDO Motors NEMA14 36mm Round Pancake Motor LDO-36STH20-1004AHG(XH) - Amazon.com

 

and here is the extruder config:

 

 

With the absurdly high rotation distance, it is currently in the middle of a print and actually seems to be printing quite well.

 

Any thoughts?  Can I run it like this, or is there something else I'm missing somewhere?

 

 

Edited November 28, 2023 by ken226

[atrushing]

25 minutes ago, ken226 said:

it was feeding filament too fast, and too much. Like, by a factor of 10x.

In your config you set the gear_ratio: to 50:1 but the stepper you linked has a 10t pinion gear. A quick change to 50:10 should help. Also, I think some of the Moons motors are 0.9° motors while the LDO steppers are 1.8° so that would be another 2x extrusion factor.

[ken226]

1 hour ago, atrushing said:

In your config you set the gear_ratio: to 50:1 but the stepper you linked has a 10t pinion gear. A quick change to 50:10 should help. Also, I think some of the Moons motors are 0.9° motors while the LDO steppers are 1.8° so that would be another 2x extrusion factor.

Jeeze.  I feel like a dipstick for missing something that obvious.

 

I guess I was thinking in decimals rather that ratios.  When I made the switch from the CW1's 50/17 ratio to the CW2's 50/10,  I think I was on autopilot or something and reduced 50.10 to 50.1

And obviously, this doesn't quite work like that. 

 

Thanks for catching that.  Going from 50:1 back to the correct 50:10 is exactly the 10x factor I was seeing.

 

I made the correction and am running another test print.  So far it's running perfectly.

 

Thank again!

Edited November 28, 2023 by ken226