Ender3 DyzenPro et SKR mini E3 v2.0

[Rsvd974]

Bonjour, j'ai une ender3 avec une carte mère skr mini e3 v2.0 avec tmc 2209 et un kit DyzendPro!!!

Tout fonctionne correctement, c'est juste au niveau de la température du moteur de l'extrudeur qui est dans les 40-45 degrés avec 

650 mA et qui saute des pas avec du tpu 87a sauf si je ralenti beaucoup la vitesse!

Est ce que en mettant vers les 900 mA le moteur chauffera plus ou pas et aura t'il plus de force?

 Merci!!!!

[Philippe Carrier]

C'est normal que le moteur soit plus chaud. 650mA est très bas, le torque est directement proportionnel au courant.

Le moteur est conçu pour 1A, mais on suggère 900mA. Cette configuration a déjà une marge de sécurité. 

[Patrick Emerick]

Hi, I received a notification about this post and I'm not sure why, but I can offer my experience which may be helpful. I recently installed and calibrated a DyeXtruder/end combo and found that at 900mArms, the motor ran much hotter than the 45C that is recommended in the manual - I was seeing about 55C at 20C ambient. To reach the recommended 45C, I had to reduce current to 700mArms. The 55C motor temperature was causing the extruder gears to eventually reach that temperature which was causing problems with filament that has lower glass transition temperature. For example, PA6 would jam frequently, but PA12 was relatively printable, so I'd assume that TPU would definitely suffer from poor extrusion with hot extruder gears. As a quick fix I added a fan to the side of the extruder to create turbulence around the fins which did help reduce the temperature. I also discovered that I could run at lower current without jamming as long as the gears remained below ~35C with PA6 material, so the skipping you're experiencing may be caused by the gears being too hot to properly grip the material. 

I upgraded to water cooling of the hotend and extruder because I generally print fully enclosed and now the system is incredible! I'm printing 3DXTech PA6+CF at 0.1mm layer thickness without any issues which I've never been able to achieve. I think air cooling as designed is inadequate for this extrusion system unless ambient temperatures are low and the heated build plate is at a relatively low temperature. If you're not printing with an enclosure and you don't want to liquid cool, I'd recommend adding a fan to the side of the motor, but the downside of this is that more turbulence will be created around the printed part. I used a  40mm x 15mm fan and a 15mm thick duct between the fan and the extruder motor - the duct had an opening at the top for the air to escape without as much air blowing down towards the part.

On Saturday, November 28, 2020 at 12:32:18 AM UTC-5 rsvd...@gmail.com wrote:

[Rsvd974]

Merci beaucoup je vais régler ça!!!!!!!!!!!! :)

[Rsvd974]

Thank you Patrick Emerick!! :)

[Rsvd974]

Re Bonjour!! Alors à 900 mA le moteur monte à 54-55 degrés!!!! Il faut que je teste entre 900 et les 650 que j'avais avant?!!

En rétraction je suis à 0.3mm et 25 mm/s!!

[Philippe Carrier]

La suggestion de Patrick est très bonne.

55°C est normal pour un stepper, mais c'est vrai que si on travaille avec des Tg faibles, ça peut devenir problématique. Si c'est le cas, un entre-deux côté courant est une solution, tout comme l'ajout de refroidissement actif.

[Patrick Emerick]

Philippe, I'd like to suggest that you change the manual for the extruder where it mentions that motor current should be tuned to operate the motor at 45C. 

The manual explicitly states:

"WARNING

If your motor is running hot, above 45°C, reduce the current by 10% until you reach a maximum of 45°C."

I'd imagine that most of your customers using the Pro extruder read and take manufacturer recommendations seriously, so this sets an expectation that current should be reduced until 45C is reached, but this will also reduce the performance of the extruder. I can attest that running at 900mArms with water-cooling allows the extruder to basically power through anything one could throw at it, but at 650mArms printing performance isn't as good, although it was better than my stock BCN3D bowden setup was.

[Rsvd974]

Merci encore à tous les deux pour votre aide!! :)

Je vais faire différents tests pour trouver un juste milieu!!

[Philippe Carrier]

I agree with you Patrick. We will change it and speak about a "normal temperature rise", and advise to tune the current if a low Tg polymer is used, as you explained before. Thanks for your suggestion!

[Patrick Emerick]

Philippe, I was just tuning current for a stepper on a CR20 I just got to mod and I realized something that relates to this problem.

As I mentioned earlier in this thread, I used an RMS current meter to tune extruder current to 0.7A rms. I think when setting the current limit using the voltage between ground and the adjustment screw, it is setting peak current. When you specify 900mA as the optimal current are you referring to 900mA peak? 0.7A rms * 1.414 = 990mA peak and 0.9A rms * 1.414 = 1.27A peak which could explain why I needed to set the current to 700mA rms to measure the recommended temperature rise. Now that I setup water cooling I am running 0.9A rms which I'm thinking may be too high for the motor?

[Philippe Carrier]

Indeed, there might be some confusion between RMS and peak current. Usually, RMS current is considered.

Nonetheless, the important factor is to get the right tuning for our application. If using low Tg filaments, a lower current should be set, until you are comfortable with the results.

With water cooling, there shouldn't be any issue, as water will remove heat very quickly and prevent any heating in the motor.