Under size prints

I having a problem with my prints being undersized. Seem to be in all directions.

Part is supposed to be 1.300" in Z and it measures 1.290" the .010" seems to be about what it is under everywhere.

Material is ABS
layer height .2mm
Noz temp 240
bed temp 110
flow 95%

First layer I have the over extrusion set to 100% not the default 150% I believe.

Being a machinist I guess Im being pretty picky. Should this be something I should just accept?

Check what you have your filament diameter set to and measure your filament in 5-10 places and take the average. The software usually sets it to 2.85mm but sometimes it can be higher or lower than this. Put in the average value for your specific filament. I’ve had some filament come in at 3.01mm.

Assuming that is correct, bump your flow rate up a percent or two, print, and measure again and see if your OD distance is better. I always assume my part will be off by about 0.2mm and account for this on my press fits and dimensions in my design.

YRMV,
Jim

Did you print out a calibration cube to verify you do not need to calibrate and adjust your X/Y/Z step settings in firmware.

I did not know this was a option and would like to do that for sure! Is this cube just a say 20x20 cube? Or is it a test print that I can find in the software? Also where are the firmware options.

This did not work but got me a little closer.

Yes just download, slice then print a 20X20X20 cube or make your own. Then measure it and if it does not match the dimensions you used then adjust the steps in firmware.

Look in the Configuration menu on the LCD just above the ESteps. Or if you have a Mini you can use gcode commands like M503 to see what they are currently set at. This command also gives you the commands to use to change them as part of its output.

I will give this a try. I have a Mini so not to confident on how to do the commands.

I didn’t even know about this! Is there a guide somewhere for how to set new steps in firmware using the mini?

I have never looked for one, so I do not know about a guide. :blush:

The M503 command will give:

Send: M503
Recv: echo:Steps per unit:
Recv: echo: M92 X100.50 Y100.50 Z1600.00 E797.60
Recv: echo:Maximum feedrates (mm/s):
Recv: echo: M203 X800.00 Y800.00 Z3.00 E40.00
Recv: echo:Maximum Acceleration (mm/s2):
Recv: echo: M201 X9000 Y9000 Z100 E10000
Recv: echo:Acceleration: S=acceleration, T=retract acceleration
Recv: echo: M204 S500.00 T3000.00
Recv: echo:Advanced variables: S=Min feedrate (mm/s), T=Min travel feedrate (mm/s), B=minimum segment time (ms), X=maximum XY jerk (mm/s), Z=maximum Z jerk (mm/s), E=maximum E jerk (mm/s)
Recv: echo: M205 S0.00 T0.00 B20000 X8.00 Z0.40 E10.00
Recv: echo:Home offset (mm):
Recv: echo: M206 X0.00 Y0.00 Z0.00
Recv: echo:PID settings:
Recv: echo: M301 P28.79 I1.91 D108.51

It is something like:

Print calibration cube then measure each axis and adjust the ones that are off.

Example:

X Axis - printed 20 MM Measured 20.1

Then calculate the adjustment needed:

(Expected dimension) / (measured dimension) * (current X Steps in firmware) = Adjusted Steps

20/20.1 * 100.5 = 100

Then type the following in the command window on the Control window of Cura.

M92 X100 <- Set X Steps to 100

then Store the new X steps:

M500 <- Store into EEProm

So I found a fff. file that finally got my Simplify 3D to work(well kind of). So I printed the same part I had dimension issues with and to my surprise it is a heck of a lot closer than the print that came from Cura. Its still not perfect but way better.

Cura part - .235"
S3D part- .245"

So Im closer but pretty disappointed that Cura is that off.

I did a quick extruder cal where you mark 110mm of filament them extrude 100mm and measure whats left. I measured 9.89mm so I would assume that I am over extruding.

Side note maybe someone can help with this and not start another thread.

  • this new fff. profile for S3D at the end of the print it doesnt move in Z off the part. Instead the head moves in X till it hits the limit switch which is not good because its dragging the head across the part.

Look in the end gcode section for your simplify3d profile.

Curas looks like this:

M400                           ; wait for moves to finish
M104 S0                        ; hotend off
M107                           ; fans off
G91                            ; relative positioning
G1 E-1 F300                    ; retract the filament a bit before lifting the nozzle, to release some of the pressure
G1 Z+20 E-5 X-20 Y-20 F3000    ; move Z up a bit and retract filament even more
M117 Cooling please wait       ; progress indicator message
G90                            ; absolute positioning
G1 Y280 F3000                    ; move to cooling position
M190 S0                       ; set bed to cool off
M84                            ; steppers off
G90                            ; absolute positioning
M117 Print complete            ; progress indicator message

Oh, one note: I changed the cooldown temp to 0. The original was 50, in this line (S0 = 0 degrees, S50 would be 50):

M190 S0                       ; set bed to cool off