<![CDATA[SoliForum - 3D Printing Community — Limits for gearing on an extruder?]]> 2014-12-12T03:22:56Z PunBB https://www.soliforum.com/topic/8697/limits-for-gearing-on-an-extruder/ <![CDATA[Re: Limits for gearing on an extruder?]]> I was considering the same conclusion, it would be pointless to gain that torque only to lose it in micro steps.  I'm going to order a motor tonight then.

]]> https://www.soliforum.com/user/3772/ 2014-12-12T03:22:56Z https://www.soliforum.com/post/74916/#p74916 <![CDATA[Re: Limits for gearing on an extruder?]]> Yes, that is correct - but with reductions like that (27:1), you shouldn't be micro stepping at all. With a 14:1 reduction I'd do a 2x microstep.

]]> https://www.soliforum.com/user/221/ 2014-12-12T03:04:45Z https://www.soliforum.com/post/74915/#p74915 <![CDATA[Re: Limits for gearing on an extruder?]]> Did a little digging, it is limited in Marlin by the frequency capabilities of the chip and electronics.  Apparently some at megas have a quad step function, anyone know anything about that?

Just so i have the limitations correct in my head, i can't go over what would end up totaling more than the 16k in one second correct? 

So say 2500 steps per mm, would limit at 16khz around 6mm/s.

Am i understanding this correctly?  Thanks for the help too, i appreciate it greatly!

]]> https://www.soliforum.com/user/3772/ 2014-12-12T01:20:52Z https://www.soliforum.com/post/74904/#p74904 <![CDATA[Re: Limits for gearing on an extruder?]]> Ahh, i forgot about the software side of things, thanks for pointing that out. 

I'm going to make up a test bench for this.  It's probably already been done somewhere but i could use the hands on.

Is the 15k limit due to a limit in frequency or memory buffer?

]]> https://www.soliforum.com/user/3772/ 2014-12-11T00:56:44Z https://www.soliforum.com/post/74766/#p74766 <![CDATA[Re: Limits for gearing on an extruder?]]> Two limitations:

1.) Available torque. Stepper torque falls off as a function of speed.
2.) Marlin's step rate. Can't exceed 15k steps/sec.

You're fine in both cases. Go with the lighter/cheaper option.

]]> https://www.soliforum.com/user/221/ 2014-12-11T00:08:19Z https://www.soliforum.com/post/74756/#p74756 <![CDATA[Limits for gearing on an extruder?]]> I'm going to be ordering a geared stepper motor soon for my bowden.  I don't think a higher ratio will affect actual printed extruding in a negative way since its so slow anyway.  I'm mainly concerned about the retraction aspect.

At the moment I'm looking at either 27:1 or 14:1 stepper.  I can go to 32 microsteps,  which if my math is right would give me about 5208 steps per mm for the extruder.  Is there a good way to figure out limitations running some numbers they have detailed for the steppers?

Here's the link for one I'm considering :
http://m.omc-stepperonline.com/item_description/41

]]> https://www.soliforum.com/user/3772/ 2014-12-10T23:49:21Z https://www.soliforum.com/post/74748/#p74748