As @carlosspr says. For stall detection to work, the feed rate in your G1 S1 commands must be at least (60 * m915-h-value / full-steps-per-mm) . If your printer has 80 steps/mm @ x16 microstepping, that's 5 full steps/mm. You are using H200 in M915, so the minimum G1 S1 feed rate would be (200 * 60)/5 = 2400.

Replaced the idlers and bearings with new stock parts, even though I find it disturbing running the belt teeth against a smooth idler. Can't get 36 tooth idlers off the shelf. So it's stock, make idlers, or modify machine frame and double a couple points up. Belts and pulleys were replaced with gates parts. Very slight improvement. Printed a delta calibration part and found the dimensions to be within reason. 60mm was dead on inline with the X tower, and about .2mm short inline with the y and z towers. As good as it's getting. I've beat this horse too long. Everything but the frame and arms are new at this point. Thanks everyone for the input. Cory

Sure, if using the wrong rod length gives you a flat bed height map and good linearity, go with it. It's probably helping to compensate for a geometrical error elsewhere in your printer.

It's been a while since I have posted anything, the X and Y error continues to grow, it's around 20 in Y now. Since I didn't want to rip out the metal arms of the endstops, I am ordering new ones with easily removable metal arms: https://www.amazon.co.uk/gp/product/B079JDB4PW/ref=ox_sc_act_title_1?smid=A282CIVY4X0P53&psc=1 In the meantime I have printed a few things, all of which turned out correctly, even though the first layer is a pain in the ass. (THe head isn't moving parallel to the bed) That's all for now, I will update this thread after I get the new endstops.

@phaedrux Lack of layer shifts aside, I would say that the print quality is as good if not slightly better than it was before. I have only run a couple of small calibration prints so far but I do intend on printing a Sir Layers-A-Lot with a filament sample tonight or tomorrow.

@adrian52 good to know!