Posts made by StevePS3

Ahh, yes, the plugin looks to be more like what I was expecting. Everything just seems to vague "Choose a shaper that suppresses those frequencies effectively"? How do I know what the shapers do. Does everything have to be trial and error?

@dc42
Yes, I have read that. It tells me almost nothing. What are all the shapers? Nothing is actually explained.

My D-bot has some fairly bad ghosting so I am hoping that input shaping will be able to help. I have wired up my accelerometer and it is working just fine. Now comes the confusing bit. How do I record any data. Even the official webpage has practically zero detail on how this is done. From the youtube videos that I've watched it looks like I need to do a print. The duet3d documentation simply says "Use command M956 to collect accelerometer data.". Do I add a single M956 at the end of the gcode, after every movement, it doesn't say? Rather than simply relying on trial and error I was hoping that there may actually be a guide showing me exactly what I need to do.

If anyone has setup input shaping then please let me know how I go about collecting data.

thanks

A value of about 30 seems to work just fine.

@jay_s_uk
Yes, that worked. OK, so now maybe I can start to tweak the settings until it works. -127 definitely causes an instant stall

I have reduced the current to the steppers so that they stall as soon as they start to move. Yet all they do is continue to try to move. I was assuming that they would stop moving as soon as they stall?

OK, I am now on 3.3 and the results are the same. Just lots of belt slipping as the head crashes into the side of the printer.

@dc42 Thanks, I'll give that a try.

@t3p3tony I set it to -64 and it still doesn't stall

M915 X Y S-64 R0 F0

@t3p3tony Yes, that is the document that I have been using

I've done a search of the forum and found a couple of related posts but so far I've not found a solution.

Board: Duet 3 Mini 5+ (Mini5plus)
Firmware: RepRapFirmware for Duet 3 Mini 5+ 3.2.2 (2021-02-11)
Duet WiFi Server Version: 1.25

I am trying to setup sensorless homing but no matter what I do, the head simple crashes into the end of the carriage and carries on trying to move.

I've set the parameters for the X and Y

; Endstops - sensorless
M574 X1 S3 ; configure sensorless endstop for low end on X
M574 Y1 S3 ; configure sensorless endstop for low end on Y

; Motor Stall
M915 X Y S5 R0 F0

I then cribbed the homeX from the documentation.
M400
M913 X75 Y75 ; drop motor current to 75%
M400 G91; relative positioning
G1 H2 Z10 F12000 ; lift Z relative to current position
G1 H1 X-320.5 F2000 ; move quickly to X axis endstop and stop there (first pass)
G1 H2 X5 F12000 ; go back a few mm
G1 H1 X-320.5 F1000 ; move slowly to X axis endstop once more (second pass)
G1 H2 Z-10 F6000 ; lower Z again
G90 ; absolute positioning
M400
M913 X100 Y100 ; return current to 100%
M400

So far I've not managed to induce a stall. Can anyone help?

@fcwilt
I think it’s a G29. It is whatever the command is under the compensate and calibrate button.

@fcwilt
Maybe. The head did go crashing into the frame of the printer until I changed the G30 positions.

Something strange has happened. I don't know why but the height map is now being created with the first point being the bottom right. Up until now the first probe point has been bottom left. Other than that not a lot has changed. The compensation is still nowhere near what it should be.

@fcwilt

I've measured the difference now and it is 3cm behind the nozzle. So I've updated the config.h

G31 P500 X0 Y30 Z3.75

I've also updated the bed.h to remove one of the
G30 P0 Y00 X150 Z-99999
and also the M29 S2

I think I was clearing the height map just so that start with a clean slate.

The G29 S1 is performed as part of my start gcode.

G21 ; set units to millimeters
G32
G29 S1
M104 S[first_layer_temperature] ; set extruder temp

I'll give those changes a try.

I did read somewhere, and this may be a complete red herring, that because parts of the bed are below zero then something needs to be done to the config to allow the head to move to a Z position < 0.

As I say it may be a red herring. It was just something I read whilst attempting to search for a solution.

I also think that I need to get my 6mm aluminium bed levelled. I'll have to find a machine shop that can skim it for me.

@argo
I am using a BL Touch. It is approximately 5cm behind the nozzle.

@argo
G31 P500 X0 Y0 Z3.75