So there has been some speculation on the inaccuracy of the Z height for prints that are attached directly to the build plate and since I've had some free time the past few days, I've decided to delve into this issue first hand.
There has been another use in the FB group who did a nice little write up in regards to the spring in the build plate as well as the spring washers internal to the stepper and I wantd to have a solution that was non-intrusive to be messing with anything like that.
Sooooo, here are my findings...
I created a simple 20mm calibration cube and printed it. Checked it's z height and measured 19.6mm, so a 0.4mm height difference.
Now, since I didn't feel the need to be pulling apart steppers and taking apart the build plate to remove a spring, I dove into the software side of things and unlocked the Z=0 menu option. Now since my particular test print was exactly 0.4mm short, this was easy. Simply, rehomed the build plate through the menu, then set the 0.1mm option and tapped the up arrow 4 times to equal the 0.4mm difference (19.6mm cube + 0.4mm offset = 20mm), then I went back one menu option and tapped the Z=0 and confirmed it. This has now set my Z axis home position to 0.4mm above the z axis stop.
I ran the calibratin cube again and low and behold... measured exactly 20mm on the z height
Right now I'm running a 5mm, 10mm, 15mm and 20mm cube at the same time to be able to verify multi-height accuracy and that this wasnt just for the 20mm cube size.
I've also conjured the way to be able to offset in values that are outside of the printers 0.1mm, 1mm and 10mm presets, but I'll address that shortly as well
So for right now, no need to mess with taking anything off the printer to be able to adjust for z height accuracy...
Update...
Pulled the set of calibration cubes from the printer and damn, all are good, so that shows that this works for any height of print Now I just have to package everything and do the writeup for the "How To", hopefully will have that done and up later this evening.
Update...
Here are the files and walk though instructions needed, ENJOY!!! I'll work on getting a video together next to also show the process...
Update...
If your offset is upwards of 1mm or more, then you will most likely need to mod the stepper with the washer or add an additional spring washer, as this means the stepper probably has a single spring washer installed instead of 2. Typical offset would be in the range of 0.3mm - 0.5mm.
Z Height Accuracy.zip (Size: 286.45 KB / Downloads: 1,411)
There has been another use in the FB group who did a nice little write up in regards to the spring in the build plate as well as the spring washers internal to the stepper and I wantd to have a solution that was non-intrusive to be messing with anything like that.
Sooooo, here are my findings...
I created a simple 20mm calibration cube and printed it. Checked it's z height and measured 19.6mm, so a 0.4mm height difference.
Now, since I didn't feel the need to be pulling apart steppers and taking apart the build plate to remove a spring, I dove into the software side of things and unlocked the Z=0 menu option. Now since my particular test print was exactly 0.4mm short, this was easy. Simply, rehomed the build plate through the menu, then set the 0.1mm option and tapped the up arrow 4 times to equal the 0.4mm difference (19.6mm cube + 0.4mm offset = 20mm), then I went back one menu option and tapped the Z=0 and confirmed it. This has now set my Z axis home position to 0.4mm above the z axis stop.
I ran the calibratin cube again and low and behold... measured exactly 20mm on the z height
Right now I'm running a 5mm, 10mm, 15mm and 20mm cube at the same time to be able to verify multi-height accuracy and that this wasnt just for the 20mm cube size.
I've also conjured the way to be able to offset in values that are outside of the printers 0.1mm, 1mm and 10mm presets, but I'll address that shortly as well
So for right now, no need to mess with taking anything off the printer to be able to adjust for z height accuracy...
Update...
Pulled the set of calibration cubes from the printer and damn, all are good, so that shows that this works for any height of print
Now I just have to package everything and do the writeup for the "How To", hopefully will have that done and up later this evening.Update...
Here are the files and walk though instructions needed, ENJOY!!! I'll work on getting a video together next to also show the process...
Update...
If your offset is upwards of 1mm or more, then you will most likely need to mod the stepper with the washer or add an additional spring washer, as this means the stepper probably has a single spring washer installed instead of 2. Typical offset would be in the range of 0.3mm - 0.5mm.
Z Height Accuracy.zip (Size: 286.45 KB / Downloads: 1,411)