While I work on fixing the many problems on my deltas, I have a question about my Cartesian. All my prints are about 3% too big along my X axis, and about 2% across my Y. I’ve double checked my measurements on the RepRap Prusa calculator - 160steps/mm. What do I do to fine tune the proper dimensions? it’s it removing the 3% from the 160steps/mm on X, and 2% off Y respectively? So I’d adjust my steps from 160 to 155.33 for X and 156.86 for Y? is it that simple?
Should be that simple, but what you will do is make a correction. Print a test, measure and doing it again until you can just live with it.
Double check to make sure your extruder is calibrated before making modifications to the steps per mm values–slight overextrusion may cause some of your small dimensional inaccuracies
@Ishaan_Gov Thanks - I’ve fine-tuned my extruder, I’ll definitely make some adjustments after my next test print.
Print a couple of parts, one twice the size of the other in one axis. Now re-measure and if it’s a steps/mm error then the bigger part should have about twice the error. Please note that if you’re also over stuffing the part then this will upset the readings a little so your parts should be quite long.
What size pulley do you use? That is super odd that it is oversizing like that
The steps per mm is a fixed value that is determined by the angle per step of the motor and the ratios of the pulley(s). This value is a hard number and should not need to ever be adjusted. Look at the extruder calibration and some of your operating parameters such as acceleration and jerk. Also, sometimes the slicer has to make compromises for the model - for example if you are using a 0.04mm nozzle and the model has a wall that is 0.05mm thick (one pass is not enough and two passes are way too much).
The test print was 40mm x 40mm x 20mm.
I first noticed prints were off on a part for a quad copter. The arms were supposed to be 105mm long, but turned out closer to 110 mm. the width was also affected. I’ve calibrated the extruder quite a bit. Maybe I’ll have to re-visit that? My pully’s are nothing fancy, 20 tooth (came with the printer).
Sounds like there are other problems I have to deal with as well based on what everyone’s saying…
@Chris_Wilson , I’m guessing you’re running GT2 belts with 20 tooth pulleys with 1/32 microstepping?
@Ishaan_Gov That’s exactly it.
@Chris_Wilson , alright, just wanted to make sure that you aren’t running MXL belt which I think has a tooth spacing of 2.032mm
@Ishaan_Gov what would change if it was a 2.032mm belt? I feel the need to double check since I bought the printer as a whole…
@Chris_Wilson , do you not notice the correlation in that number? 2.032 is approx 3% off…
@Mark_Rehorst Thanks. That’s what I’ve started doing. First test print is much more accurate. I still have to adjust my Y value a little.