Jump to content
Ultimaker Community of 3D Printing Experts
Sign in to follow this  
elmsi89

UM2 - Stepper Motor Speed (rpm)

Recommended Posts

Hi,

I am thinking about the Flow Rate Setting regarding the practical and the theoretical Extrusion Rate and the following grinding-problem through a too fast moving stepper motor. I don't know if the Flow is somehow connected to the stepper-motor speed, but to verify that, I need to know how fast the motor really is. So, can you guys tell me that?

Best Wishes

 

Share this post


Link to post
Share on other sites

I don't understand the question and what the speed has to do with it. The speed of all the motors change together on every (many) line segments. So they are constantly speeding up and slowing down. The faster you move the XY axis, the faster the E (Extruder ) axis moves. All XYZE moves are linear. To achieve linearity you have to run the E axis very slow compared to how fast is possible.

The speed of the E axis is set by the speed of the other axis. So for example if you are moving the head at 100mm/sec with .2mm layers and a .4mm nozzle that is 100*.2*.4 or 8 cubic mm per second. So the E axis moves at the correct rate to extrude 8 cubic mm per second.

 

Share this post


Link to post
Share on other sites

I don't understand the question and what the speed has to do with it. The speed of all the motors change together on every (many) line segments. So they are constantly speeding up and slowing down. The faster you move the XY axis, the faster the E (Extruder ) axis moves. All XYZE moves are linear. To achieve linearity you have to run the E axis very slow compared to how fast is possible.

The speed of the E axis is set by the speed of the other axis. So for example if you are moving the head at 100mm/sec with .2mm layers and a .4mm nozzle that is 100*.2*.4 or 8 cubic mm per second. So the E axis moves at the correct rate to extrude 8 cubic mm per second.

 

And that's without counting for acceleration, which makes the whole thing a lot more difficult.

 

Share this post


Link to post
Share on other sites

Yes, if you set flow to 50% you will get half as much plastic extruded as normally needed. Or 200% will give you double.

So for example if you are printing a solid layer and there are gaps between each line and the gap is 10% as wide as the line you can increase your flow to 110% and it should fill perfectly.

I haven't changed my flow from 100% since about a year ago. 100% works almost always perfectly for me.

 

Share this post


Link to post
Share on other sites

Ok, then I understand the thing really. My problem is grinding at lower printing speeds, but everything else is just fine. Neither is the hotend clogged, nor anything else lose. (and if I can't get better results with the flow setting, I know at least more about my printer)

So, thank you two. You helped me a lot. :)

 

Share this post


Link to post
Share on other sites

You might have too much pressure in the feeder if its grinding filament. It can also be cause when too much pressure is in the bowden tube due to irregular filament size or previous grinding that produce a chunk of filament that is stuck between the filament and the tube...

Share this post


Link to post
Share on other sites

Try increasing the temperature by another 10C (but I recommend not going any hotter than 240C) which will reduce the pressure in the nozzle. Also maybe reduce the spring pressure (or increase but more likely decrease) on the feeder.

 

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  

Announcements

  • Our picks

    • Architect Design Contest | Vehicles.
      We're open for entries! - Design and submit your 3D designs of architectural entourage - vehicles - for a chance to win a large filament pack. Presenting an idea, an architectural design or something as big as an urban project isn't easy. A scaled model can really help to get your idea across.
        • Like
      • 14 replies
    • What The DfAM?
      I'm Steve Cox, an experienced engineer familiar with 3D printing. I wanted to share some DfAM guidelines with this community to help and make stronger parts.
      I'm also an Autodesk Certified Instructor for Fusion 360, so many of the images in ...
        • Thanks
        • Like
      • 17 replies
×

Important Information

Welcome to the Ultimaker Community of 3D printing experts. Visit the following links to read more about our Terms of Use or our Privacy Policy. Thank you!