RE: X-axis layer shifting
Honestly, set screws are a pretty terrible way to secure pulleys to shafts. They're well known to be unreliable, and plenty of cheap alternatives exist. For this application, the optimal fastening method is glue. No, really. The shear strength of something like Loctite 638 exceeds set screws, requires less machining, and doesn't come loose.
Here's a white paper on motor shaft attachment methods:
RE: X-axis layer shifting.
A toaster makes toast automatically and is hard to mess up. Not a toaster means it won't be automatic, and you can try all kinds of things to varying degrees of success of failure.
From your sideways to convention spool feeder, as long as you align the longitudinal axis of all your prints to be left to right, that spool holder arrangement will probably feed ok. If you start to align your longitudinal object axis on the Y plane, you'll start to introduce tugging as the print head moves, which sometimes can cause layer shifts. Add a limited width filament guide and the tugging can be redirected, but you will get more tugging when the spool is full (inertia of approx 2.2 foot lb from the picture) and as the spool gets near the center the winding lash will start to pull again.
I have taken to realizing the impact of spool, spool holder geometry, and spool current start print mass on the tugging impact that can make some "ready to fail" over tight axis rod/bearing combos and/or speed on the print at hand. For full spools, make it not jig side to side by aligning print longitudinal axis with general spool spin (bicycle tire). You want to prevent over-run, and you want to prevent back-lash, and you want to prevent the windings from leaving the sides of the spool
RE: X-axis layer shifting
@dan-rogers
No - it doesn't. Works much better than the perpendicular holders for exactly the reason you state. The extruder moves left right, filament flows directly off the spool and slack is just slack, zero tension. When more filament is needed, the spool turns, providing the filament: no side to side tension that might pull filament off the spool.
When using the stock holder, the extruder is constantly yanking on the spool, trying to rip filament off from the sides.
RE: X-axis layer shifting
@rachel
Glue works great - I agree. But if maintenance is needed, removing a glued on gear will test your patience. A set screw on the other hand ...
RE: X-axis layer shifting
The counterargument is a glued pulley will never come loose, and never needs realignment.
RE: X-axis layer shifting
@rachel
But neither will a properly set gear that only has set screws. My pulleys have been on for more than three years and not once have I had to do anything but realign due to changing other hardware. Not once have they come loose. 99% of the posts here regarding a loose pulley - you can see from pics they were never installed correctly. And had these same people used glue --- lmao --- the resulting frustration they'd have trying to undo that mistake would be almost hilarious.
ps: set screws are used in the industry because they do work; they are reliable; and they are maintainable. Just search for any power transfer hardware that says "we recommend gluing" ...
RE: X-axis layer shifting
Thansk so much Rachel for posting this. I was going nuts due to the same issue. I did everything (or tough I did it). Even re-assembled the printer using a wrench with precision torque. But nothing worked until I found your post.
I simply moved the original filament holder to a side in order to set the filament just over the model being printed and voilà. No more X-axis layer shift. Thanks so much
RE: X-axis layer shifting
It does make sense....
RE:
Hi!
I have the same problem (after about 3 years of not very intensive use). I noticed a movement of the shaft in and out (relative to the X-axis motor) that can be explained by what you describe.
Can you point to a page for disassembly (and re-assembly) of the X-axis motor block?
Thank you