Greetings all from the snowy capital of Canada.
Jason and Lauran a tip of the hat again to you both for your help and dealing with the challenges we had back when I purchased the CR10 Smart, and ended up returning it for the CR 10 Smart Pro - definitely a better performing machine 
Would it be possible to get the CR10 Smart Pro added as a category?
On to the technical question of the moment (for me):
I’ve run a handful of prints with success, but had to shift focus away from the unit for a couple of months. When I came back to it, I printed a couple of models very successfully, then suddenly nothing would stick to the PEI sheet. I cleaned, cleaned and cleaned that beast, finally gave up and used UHU glue stick. Just how prone to contamination are the PEI sheets? I’ve used nothing stronger than dish soap and 99% IPA on the textured surface to date, and I’m aware some out there suggest a light wipe with acetone and others suggest a mild scuffing with 1000 grit, or a bit higher grit sandpaper. I’m loathe to go down that road just yet. I clean with IPA after every single print so I’m really puzzled on why suddenly I needed to go to UHU… Just looking for possible reasons - it works so I’ll do it.
Secondly, I’ve got an odd tramming issue. After a manual adjustment using the 5 points and the supplied .1 mm paper strip, followed by an ABL for the full 25 points, and using a Z offset of -1.45 or -1.50 and then running a 5 squares single layer print, I get really varied results across the entire bed. Doesn’t matter which Z offset I use. I’m not scratching the PEI surface in any visible manner either.
What I see: At the origin (front left corner of bed), the square prints, there’s a tiny bit of line to line stick but basically we have a lacey square that can be stretched into a single line. Go to left rear corner and the filement gets put down, but there is negligible stick between lines - like no squish happened, but in fact some did as the filament is flattened. Move to the center and approximately 50% of the square is lacey like the leftmost two, and the other 50% is perfectly fused into a single sheet. Moving to the right rear, and we’re seeing solid bed adhesion, and the filament is fused into a sheet, but has pilling or orange peeling as some call it, happening. The final spot - front right gets a perfectly printed single layer square with no pilling/orange peeling and is a perfect bit of plastic film.
This suggests a couple of things to me:
- There is variance in my two Z axis, such that my left side is always ever so slightly higher than my right side.
- There is a bug in the software code that is consistently applying the wrong Z offset to the ABL mesh after probing.
For Item 1, it’s either mechanical - and a small manual adjustment of the left side Z axis lead screw will fix (requires Vernier caliper and a reasonably flat reference surface - I think I can rig up a level to do that) or there’s a problem in the stepper driver voltage for one or the other side and it needs to be brought back in sync. Not sure as yet, how easy that’ll be to deal with. Thought’s?
For Item 2, ugh. I honestly don’t feel like delving into source code for Marlin FW. I’ve done some of that with the GeeeTech I3 Pro W and while parts of it were easy to tweak I never got it to accept a custom adjustment for the BL touch I added to improve that printer’s results (I plan to get back to that, but larger projects demand my time more)