Ratcheting/Banging when Moving Left on Startup  

Re: Ratcheting/Banging when Moving Left on Startup

Annnnd, immediately solved the problem.

So if anyone else runs into this I believe it was that the pathway for the blade was a bit messy on the printed piece. That (or something else.. but that was all I changed to remedy the issue) was getting in the way of the unit moving right, then it would assume there was way more travel needed to move left when it moved back in that direction. Causing it to ratchet against the side of the MMU 2.0 assembly.

I ran over the pathway with a metal pick to clean it up and also manually rotated the carriage back and forth a few times until there wasn't a slight hesitation on one area.

Re: Ratcheting/Banging when Moving Left on Startup

Mine jams against the left side twice every time I start up. Once immediately on power-up as part of a full left/right movement, then once the mk3 shows the info screen it flashes and does it again. Everything seems to work, so I thought that the multiple collisions with the left side were normal, just repeatedly testing the leftmost position.

Now you have me curious. Can you post a short vid of your ‘good’ startup? Mine makes it all the way to the right (I think).

I’m printing now, but I’ll post my startup sequence video in the morning so everyone can tell me my mmu2 is broken 😉

Re: Ratcheting/Banging when Moving Left on Startup

I'm jealous that you're printing! Still having some teething issues I can't figure out with feeding and retracting basically breaking every time it tries.

As I'm going to record a short startup sequence video now that it looks correct anyway (couldn't find one so that I could compare) I'll do an extra short clip for you of just the initialization on mine for comparison.

Re: Ratcheting/Banging when Moving Left on Startup

[youtube]r-GcRgDzZSM[/youtube]

And there's your video. Please excuse the shaky cam. I didn't have it set up for the tripod or lighting and had to hover it on two tripod feet.

Re: Ratcheting/Banging when Moving Left on Startup

To follow up on the issue a bit.

The MMU 2.0 has been, periodically, hammering to the left again on startup. I'm currently thinking that it might be the tolerances on the plastic slider for the carriage not being tight enough and some of the rough plastic catching when it moves right, making the unit think it's reached the end.

If that's the case cleaning it all up with some sandpaper will probably permanently fix the issue. Doing so (a little bit, not completely) seems to ameliorate the problem temporarily.

In any case here's what your MMU 2.0 unit shouldn't be doing on startup. See the first YouTube link above if you'd like to see the way it's supposed to work.