DPDT relay? I had to look it up. I did not know about this. Ok, this could be a solution for standalone use. But for this special case I found it easier to use the arduino of the Filawinder. To make this clear: I do not use a standalone arduino. I flashed a modified firmware to the arduino of the filawinder and used the ports on the pcb.

Would it not make is less complicated and possible cheaper to use and  DPDT relay (~$5,-) instead of using an arduino? Disclaimer : I have no electronics skills at all!

yes indeed, the endstops trigger an immediate stop of the movement (even if the last step is not fully done) and change the variable for the direction. With the next trigger of the spool rotation the guide will move a full step in the new direction. In my actual built I fixed the endstops with screws. The initial idea was to have them moveable for different spool sizes. I'm thinking about this but did not find a good solution till today.
By the way: Today there is no real use of a different trigger impulse from right or left. But I think of some features for the future . Maybe it is useful to count layers or something like this.

I'm I correct in understanding that for the wickelautomat you use the two endstops to trigger the arduino to switch the direction of the stepper?

Regards
Thomas

Love the project! Could not read the real fine details because my German is not that good but really like the idea!

This is an excellent project! Will you be sharing the STLs for the new parts?

I will try the trick with the srew and the PTFE tube. But in the moment the machine is running. I will tell, when I have done this.

Good night ..

Google translate version - https://translate.google.com/translate? … edit-text=

For tension, you could put a short PTFE tube in the guide.  Then add a screw into the side of the guide to push against the tube and pinch the filament.  You could adjust the tension exactly how you want by how far you turn the screw.

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