1

Topic: 0,5-1mm wider print than model

Hello guys,
Before I printed only jodas and something like this and didn't notice that print is not at the same size as 3D computer model.
Now I needed to print precize detail and understood, that instead of 2mm wide wall it prints 2,5 or 3mm. How to fix it? I calibrated extruder step rates before.

2 (edited by Tomek 2013-11-14 12:57:28)

Re: 0,5-1mm wider print than model

(1) Extruder step rates. Congrats! you did this

(2) Extruder multiply. Print a single wall part, and specify the wall thickness (0.42 is pretty standard) in the advanced tab. Measure the single wall thickness, and if it's too much (as it seems you're suggesting) then go to your filament tab in slic3r and change the multiplier to reduce the thickness.

(3) X-Y calibration. X-Y steps should be ok but it can benefit from belt calibration. That doesn't sound like your problem though.


USE GOOGLE AND SOLIFORUM SEARCH. This stuff is all here smile.  It's also on the solidoodletips wordpress (google solidoodletips wordpress) which should be required reading for all solidoodle users tongue.  Even though Ian hasn't updated much it has a lot of great stuff for beginning.

3

Re: 0,5-1mm wider print than model

Small calibration models will get you in the ballpark, but you really need a larger piece to tweak X and Y accurately. See:

http://home.comcast.net/~tomhorsley/har … %20and%20Y

I ran the out of calibration version of my electronics cover plate through a flatbed scanner to compare the hole positions on the original cover plate and calculate how far out I was in X and Y. That got me dialed in very accurately.

4

Re: 0,5-1mm wider print than model

Guys, thanks.. But so much information and variables to be fixed, that I am a little bit disorientated. big_smile
Again tested extruder steps, it is perfectly calibrated, then why I need to type multiplier like 0,76 - 0,8 to get single wall as 0,42mm. Have 1.75mm thread and standart extruder. Classical SD2 pro.
As I understand this multiplier is like compensation for wrong steps, right?
Then it seems that I need XY calibration? (Have watched video, but hard to understand what is he doing)
And else - small single wall box always is not 10x10x10mm, but something like 9x9,1x9,2, as I understood it should be 10x10x10.. though that it is besauce of Z stopper, but also if i make less strain on Z layers, they are not close enough to each other and height still under 10mm...

5

Re: 0,5-1mm wider print than model

Print a 25mm cube. 

Note which orientation (arrow for front or similar, otherwise it is hard to figure out which is X and which is Y direction).

Measure with calipers to get exact dimension. 

In the EEPROM menu is a number of steps per mm for X, Y, Z and Extruder. (If you have done the extruder calibration you have used this menu).

Alter the X and Y steps based on the cube dimension.  e.g. if the cube should be 25mm and is actually 20, then your steps needs to go up about 25%.  Existing steps  / (Measured dimension / Required dimension).

Give it another slice and print, should be closer. 

The multiplier impacts the calculation of filament diameter, nozzle size and required wall thickness (and may vary from filament batch to batch, based on other forum entries). 

If you print the cube single wall then measure the wall thickness, it should be the 0.42 in the slicer settings.  If the thickness is out, the multiplier is a "fine tune" to get the calculation a bit closer.  If you measure the thread, you may find it is actually closer to 1.65 (or even 1.6).  Between that setting, the extruder steps and the multiplier, you should be good for fairly accurate plastic extrusion.  Then the X and Y gets you accurate sizes on the model.

6

Re: 0,5-1mm wider print than model

Thanks. Corrections for x and y in EEPROM fixed the problem with not precize mm for detail with large enough parameters, i mean for 25mm box. But single wall 10x10x10 box still is smaller like 9,3x,9,4x9... Perhaps there are some deformations because of temperature or any other ideas?