Cura 5.3.1 prints came out larger than actual design.

[newbie3d 0]

I created a square (suposedly square) of 5" with a 4" center hole.  Cura produces a 5.49" square with 4.46" hole.  Is there anything in the setting I can adjust this?  I was using older version and I don't remember having this problem.  

Edited May 13, 2023 by newbie3d

[GregValiant 1,251]

There are a few settings that can effect the final size of a model but a 10% increase should be easy to find in the settings.  In addition, the Cura preview will show your model at the printed size.

With all the settings visible, look at the Horizontal Expansion numbers and in the Material section look at the Shrinkage numbers.

At the beginning of the gcode are the Maximum and Minimum numbers of the print.  These include the skirt/brim but with a calculator and some patience you can get the model size from those numbers.  You could slice the model with Bed Adhesion turned off and then check those numbers.  The width should be 5 inches minus (1) line width.

 

The problem can also be on the printer side, but that's a very, very low probability as the XYZ steps/mm pretty much never need to be changed.

[newbie3d 0]

GregValiant,

 

Thank you.  I had the Shrinkage/Scale set to 110%, which explains the 10% increase, I think.  I will have to reprint to confirm this after figuring out how to fix the print came out not square. I was trying to fix the wall line separation problem and I thought increase it by 10% helps the wall line overlap each other.

Edited May 14, 2023 by newbie3d

[GregValiant 1,251]

"...how to fix the print came out not square"  

That is a printer problem.  if the "X" and "Y" axis are not exactly "perpendicular / 90° / Square" then the "Y" bed trolley is running crooked to the "X".

Everything starts with a calibrated frame.  You need a carpenters tri-square and a long-enough steel straightedge

[newbie3d 0]

hmm I wanted to mark GregViliant's response as solution but somehow it marked mine. Sorry, nop

[newbie3d 0]

4 hours ago, GregValiant said:

"...how to fix the print came out not square"  

That is a printer problem.  if the "X" and "Y" axis are not exactly "perpendicular / 90° / Square" then the "Y" bed trolley is running crooked to the "X".

Everything starts with a calibrated frame.  You need a carpenters tri-square and a long-enough steel straightedge

I checked with a 8 inch Square and it seems square.  Right now I will do trial and error by lifting two opposite corners up and print until it's square.

[GregValiant 1,251]

All the open frame cartesian printers are necessarily similar.

• The rotation of the "Y" beam about the "Z" is adjusted by loosening the screws that come up from the bottom of the lower main cross beam.  The rotation about the "X" is adjusted by loosening the screws that come in from either side and are below the "Z" uprights.
• The rotation of the "X" beam is adjusted by loosening the trolley brackets that ride on the "Z" uprights.  On my Ender it's a PITA because the left screws are hidden by the bracket.  I've drilled a hole in the left Z upright to allow me to pass an allen wrench through and get to the inboard screw.  I leave the outboard one tight and let it be a pivot point.  That allows me some up-down movement at the right end and I can get the "X" beam perpendicular to the Z uprights.
• The Z uprights must have their front faces parallel.  The adjustment is to loosen the mounting screws that come up from the bottom.  They must also be parallel when viewed from the front.  The adjustment is the top crossbar.
• The "snugness" of the trolley wheels is accomplished by adjusting the cams of the wheels that have hex features.  When adjusted correctly, you should just be able to turn each wheel with two fingers.
• Belts should "twang like the strings on a bass guitar".
• The Z lead screw must remain parallel to the Z upright as the X beam travels upward in the Z.  The adjustment is to shim the Z motor mount (I ended up with .012" shim behind the motor mount).
• Calibrate the E-steps.

My monthly PM is to go back over all of that to make sure nothing got out of whack.  I level the build plate without the glass on it because I level with a piece of paper and the constant adjustments can cause it to have a slight bend cross-corner.  Lastly, I trim back the bowden tube at the hot end fitting by about 6mm and leave a nice square cut.  The tube constantly rotates in that fitting and gets chewed up by the blades in the fitting and loosens over time which can cause a gap to form between the back of the nozzle and the bottom of the tube.  That can cause clogs.

 

When all of that is copacetic, the printer will print dimensionally accurate parts.  The "Flow" may need to be touched up for particular materials (EX: I run PETG at 105% flow for all features) or for particular models (rare unless of a special situation like a single wall model).

You always need a good baseline and starting with a printer that you KNOW is accurate is a big part of that.

Edited May 14, 2023 by GregValiant