Interior Dimensions Accuracy


#1

When printing I find all outside dimensions and diameters are ±.1mm of nominal which is great! (Excluding seam line defects)

Inside features and diameters I always find are too small by ~.3mm  This is very problematic for me and the mechanical parts I need to prototype. Alot of my parts require bearings, optical components, motors etc.

I am forced to change the cad model before slicing in Z-Suite for all holes and inside features to account for this variation. This is a major pain! Once I do this then it is within ~±.1mm which is great.

I can't use the offset command becuase

  • Does not have the resolution required. .1mm to .2mm offset changes the Ø by .2mm-.4mm and I need .3mm
  • I have cross holes in many holes so the offset function does not work where the holes break into the main bore so it leaves a step.
  • Offset command does not work on features like square pockets or slots.

I can't use the scale command becuase:

  • I don't want to change the outside feature size and overalpart size.

Possible solutions to my challenge:

  • A way to adjust this in software by the user so you can "dial out" the error. (don't make it so dumbed down - give some adjustability!)
  • Perhaps have a calibrated part that the user can measure and input in the measurements back into the software so adjustments are made by the software that way future parts that are produced are spot on.
  • Provide a way to for the user to make plus and minus compensation for interior and exterior features. (I think of it as cutter compensation in the CNC machining world- think of the injector as a tool.)
  • Perhaps it is a bug in the slicer?

Knowns:

Same Issue on V2.1.0 & V1.12.1 (I did not test others)

Same result with Ultrat and Z-ABS (more of my testing was with z-abs, I did not test other materials)

What do others find when measuring components?

Attached Files:

Scan0012.pdf - is a measurement of the NO OFFSET .14 QH IMAX.zcode( Sorry it is in inches! Silly americans I know :-)

NO OFFSET .14 QH IMAX.zcode - This is a 11 minute part run so you can run if you wish, Note the hole and half moon shape is only half the error.

STAIR STEP WITH HOLES .14 QH I30 NO OFFSET.zcode - A made this part to check both the x and y external features were all pretty good but all the internals were off constantly .3mm square or round.

Thanks for the consideration!


#2

FWIW, I find the same thing. Interior dimensions are around 0.3 to 0.5 mm too small.

It's annoying.