Solved Y axis, lost steps?

I'll recheck the cable routing to see if something may be binding as the carriage moves upward.

As far as the belt tracking goes, I've played with the cog placement a bit and the results are not always what I expect. One thing is the belt, on both axes, will track from one extreme to the other as I move back and forth, to and fro, along either axis. Does this on the idlers as well, but not always in a consistent way. There does not appear to be any play in the idler bearings, but there is some "wobble" it the drive cogs. I am considering ordering new ones.

 

Oh, I meant the cog drive itself wobbles a bit. Set screws are tight and I can see the end of the end of the shaft. I resorted to a shim on the mount for the X axis idler to make it more (or less?) "square" (orthagonal?) to the direction of travel. That, at least, has it centered on the idler bearing for some of the travel.

The Y axis, I made sure the belt ends were firmly seated on the anchor ends and had to make up paper spaces for those to take up side to side slop and push them to one side. That helped tracking there, but is is close tor rubbing at either extreme of travel. I don't think rubbing on that part is causing the failure as a the print is centered on the bed and clearance in that area is fine. At least when looking with the bed off and the unit cool. It would be a real challenge to fit up a borescope camera or something to get a look at failure time.

 

New discover today. A revelation? While recovering from a botched print due to bad adhesion (I thought) and attempting to move the bed, manually directing +Y motion via Matter Control, I found the bed stopped, responding about 2/3 of the max travel.

No noise, no nothing. The bed resisted manual movement, until powered off. Then it was free and moved smoothly, full travel. After a bit of messing around, I found it would go full travel if I did a "Y" home first.

After another long-ish print that failed with the top layers displaced -Y, I found the same issue. I did not note if the "step counter" indication, which I guess would have told me something about where the software thought the printer was.

Question becomes, what could be causing this? Still simply loss of steps for some reason , mechanical, electrical?

 

Finally, success.

The solution was to lower "Speed for Non-Print Moves" (MatterControl) from 150mm/sec to 100mm/sec. It finally dawned on me that the failure was related to the shape of the print. There are areas where is does not extrude and the printer moves at this higher speed to get into position to extrude the next bits.

There was a hint, earlier, that I missed. When starting a print the final motion after "self leveling" would come to a rather noisy stop. I thought this odd, but has dismissed it as it did not seem to cause any problems. But, it nagged at me and upon investigation found the setting for non print moves. I lowered that arbitrarily and the noise was gone. Suddenly, I sensed success and a print seems to have proven that out.

I could probably raise the setting to something under 150mm/sec, or, perish the thought, research what default setting for this printer *should* be, but, hardly seems worth cutting short my basking in my own sunshine. Or something like that.

Thanks for all the assistance. At the very least it was a learning experience and I ended up with a smoother and quieter Y axis.

PS - I just did a test fit of the mask shell. Apparently I DO have a rather big nose. Apologies to "The Life of Brian", cast, crew and writers . . .