Extruder position wrong

I do have an issue with my Smoothieware and the extruder. It does not move to where it should. For calibration I issued subsequently the following:


The extruder does not stop where it started, but there is no rule about it. Sometimes is moves slowly on start, sometimes not. When it has that slow part, the original position is not reached again and it moves more back than forth. When it starts fast it does reach the original position. Over time it moves more back than forth, never the other way round. It’s really weird.

XYZ move as they should. I already swapped driver and motors so this is a firmware issue (as I see it). Here’s my config:

M115 -
FIRMWARE_NAME:Smoothieware, FIRMWARE_URL:http%3A//smoothieware.org, X-SOURCE_CODE_URL:GitHub - Smoothieware/Smoothieware: Modular, opensource, high performance G-code interpreter and C, FIRMWARE_VERSION:alu-f7df5f1, PROTOCOL_VERSION:1.0, X-FIRMWARE_BUILD_DATE:Aug 31 2021 13:47:11, X-SYSTEM_CLOCK:100MHz, X-AXES:5, X-GRBL_MODE:0, X-ARCS:1, X-CNC:0, X-MSD:1, X-WARNING:deprecated_MCU

M503 -
; No config override
;Steps per unit:
M92 X160.00000 Y160.00000 Z1435.00000
;Acceleration mm/sec^2:
M204 S3000.00000
;X- Junction Deviation, Z- Z junction deviation, S - Minimum Planner speed mm/sec:
M205 X0.05000 Z-1.00000 S0.00000
;Max cartesian feedrates in mm/sec:
M203 X200.00000 Y200.00000 Z15.00000 S-1.00000
;Max actuator feedrates in mm/sec:
M203.1 X200.00000 Y200.00000 Z15.00000
;Temporary settings S - delta segs/sec, U - mm/line segment:
M665 S0.00000 U0.00000
;E Steps per mm:
M92 E348.0000 P57988
;E Filament diameter:
M200 D0.0000 P57988
;E retract length, feedrate:
M207 S3.0000 F2700.0000 Z0.0000 Q6000.0000 P57988
;E retract recover length, feedrate:
M208 S0.0000 F480.0000 P57988
;E acceleration mm/sec²:
M204 E1000.0000 P57988
;E max feed rate mm/sec:
M203 E80.0000 P57988
;PID settings, i_max, max_pwm:
M301 S0 P22.2000 I1.0800 D114.0000 X255.0000 Y255
;Max temperature setting:
M143 S0 P300.0000
;PID settings, i_max, max_pwm:
M301 S1 P10.0000 I0.3000 D200.0000 X255.0000 Y255
;Max temperature setting:
M143 S1 P300.0000
;Home offset (mm):
M206 X0.00000 Y0.00000 Z0.00000

What board do you have? This sounds like an issue we’ve seen some of the counterfeit boards exhibit, please contact your seller and ask them to ensure the board you got is legitimate, there are more and more people selling counterfeits with the recent worldwide shortages of the “non-counterfeit” chips putting pressure and making legitimate chips cost over $100 just for the chip itself.

It’s a bigtreetech skr v1.3. But honestly, that does not look like a hardware issue. As said I swapped motors and the Pololus. But only the E-move is doing that strange thing.

I’m not saying it’s a hardware issue, quite the contrary, I’m saying it’s software/firmware.

You have two issues, one for sure, one potential.

  1. You’re running at 100Mhz, when Smoothie is coded/designed to run at 120Mhz (saves the manufacturer under $1 ). That has been known to cause all sorts of issues, including crashes and erratic step generation/planning behavior (exactly what you are seeing ).
  2. It’s possible they used a counterfeit microcontroller (made much much more likely if you bought the board after the worldwide chip shortage started, at which point they started using these a lot more often). This could cause all sorts of issues, including possibly what you are seeing.

It could also be something else though. For example, it’s not the tightest match, but we see behavior that looks like this if you have a false contact between the motor and stepper driver (on one out of four wires).

I think there might be other possibilities, but none that come to mind easily right now. Maybe somebody else will have an idea. Also I think I’ve heard a similar story a year or so back in this forum, so maybe search the forums for similar issues (don’t trust my “one year” estimation it might be way off).

Hope you figure this out.

Hope dies at last :-/ Anyway, thanks for replying. Bought my board April, but building my printer was stuck for a while. It’s only now that I started testing.

I think I read some thread about “holes during extrusion” but it did not look like being the same issue. I might read it it again.

P.S. It was this one: extruder/print problem which looks like the guy should clean the nozzle…

Uhm, well. I just looked closer on XYZ and they seem to have the same issue. Looks like that board is for the bin then :frowning:

I’m working right now so I can’t find them myself, but I am certain there was at least one post with the same problem as yours here (or in one of the other smoothie forums/mailing lists etc, see list of community hubs at smoothieware.org, top menu), maybe (probably) two.

And at least one of those was determined to be due to a counterfeit chip (there are ways to know if a chip is counterfeit, I believe the instructions are in an application note from NXP).

But again it’s possible this is something else

Just started read the WHAT IS WRONG WITH MKS ? section. I wasn’t aware of that when purchasing the board. Maybe I have to resort to MKS’s binary. I like the Smoothie approach, so I would buy an original - unless it will cost a fortune. I’m just doing that on a hobby base. I’ll see what will come out.

That’s pretty sad. Unfortunately, most boards around are going to have similar issues with the worldwide shortages.
I know one seller (i don’t remember their name), was selling Smoothieboards for like $300 a while back, because the (non-counterfeit) LPC1769 they needed to build them, cost them over $100 a piece. They ran out of stock though.
Also, I know robosprout (robosprout.com) managed to find (in some weird/exotic eastern europe shop) a hundred or so genuine LPC1769, and they made smoothieboards with them, but I suspect those sold out (or if they have not, they will soon). If you manage to find some there though, they are super nice in that they are not overcharging for the board (I think) despite paying (I think) at least $60 per chip (instead of the normal $10).

1 Like

Yep, I just took a look. Nowhere available, except for that US shop. 185$ is too much for me. Plus customs and shipping (even more CO2). I’ll try that Marlin source they pointed out at MKS. If that won’t work I’ll resort to another hobby controller (somewhat around 50€ or so). Another lesson learned.

I installed the Marlin firmware and it seemed to work. The ad for MKS claims that it runs Smoothieware. Well, yes. But only if you do not care about exact stepper positions :-/ Hopefully someone will find this thread before buying that board.

That would make sense: Smoothieware really is optimized to use 100% of the chip’s capabilities, so if you give it 100Mhz instead of 120Mhz, you’re asking for trouble.
Marlin however, is really optimized to run on 16Mhz/8bit boards, and then ported to LPC1768/9, in which case 100Mhz or 120Mhz isn’t really that much of a difference…

Actually, that gives me an idea.
If you still have your smoothie firmware and config, I’d be curious to know what happens if you add the following line to your config file:

base_stepping_frequency 40000

I would appreciate if you tested this, and told me if it fixes the issue or not.
If it does fix the issue, you’d be potentially helping a lot of users who will unavoidably run into the same trouble as you.

Thanks no matter what you decide to do.

1 Like

Will do tomorrow. Just went to bed :slight_smile:

That did not make a difference. Still the stepper starts randomly being slow. If you got any other idea I’m happy to help since it’s easy to test for me and I’m still in the phase of setting up my printer. I guess that even later it would not be an issue to test anything :slight_smile:

1 Like