Parametric Hangable Any-Direction Continuous Slip Clutch with optional Auto-Rewind Universal Spool Holder

by riskable Feb 5, 2019
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Small question: what stl is to be printed to have the accessory ball connected to the undershelf bracket ?
Is it the ball with the long peg or the ball only with a 15 or 20mm peg ?

Depends on the accessory... The longest one should fit everything though as I made all of the holes go all the way through in case a peg breaks off inside (so you can use something like a small screwdriver to bang it out).

I downloaded this on April 8, and took a week or two to print it out and assemble it. I've been using it since then with the ID badge retraction. Today the badge spool finally gave up, the string separated at the spring end. At least it's a cheap part to replace, and it's still usable as a spool holder until I can get another badge holder. Think I'll go on Amazon to see if I can find one with a stronger cord, maybe.

For reference, I've found these to be the most reliable badge holders for this application: https://smile.amazon.com/gp/product/B07DHL31GW/

Haven't had one break yet but if they do who cares, really? They're super cheap! hehe

I got a similar pack, but with a Kevlar cord. https://www.amazon.com/gp/product/B07GXG2NDG It should be arriving tomorrow.

I'd like to use this horizontally on top of a delta printer. Do you mind if I remix it? Any help would be greatly appreciated.

I love this design and it is perfect for what I was looking for. A few questions and observations as I was going through it myself.

1) I initially was going the M8 route, but found the Shaft Base and Collet only fit 5/16 nuts, not M8.

2) I think the bare minimum someone would want to get rods in is ~185mm / 7.25in. I first ordered 150mm M8 rods, but found they were too short. I finally decided to steal the 5/16in rods off my unused CR-10, and cut it to 7.5in.

3) With the retractable configuration, how snug should the inner portion be on the rod itself? It doesn't seem like you want it free flowing, but also don't want it too tight, since you want it to move when the ID badge is fully extended.

I initially tried the badge holder on, and it seemed ok, a bit noisy when it would max out, but then on another print, I glanced over at the printer and the vertical mount and found it had lifted the holder up and towards the hole (prusa lack enclosure, so spool is on top of the table being pulled down the hole), so it seemed it had too much tension.

Overall love the design and plan to make some more. :)

1) M8 nuts should fit. I mean, that's what I'm using! Of course, the M8 nut standard allows for some wildly different external dimensions (the standard is more focused on the internal thread than the actual nut). Yours might be slightly bigger. It's plastic though: Just cram it in there! Use a strong clamp or vice... The Shaft Base should be big enough that it won't crack or anything.

2) I believe I suggested using 200mm rods somewhere (I'll double-check if it's in the main Thing description). I'm using these: https://smile.amazon.com/gp/product/B01M9D9EDS/ . 5/16in or M8 rods should fit just fine. The 5/16in rods are only going to be 0.0625mm skinnier than the M8s.

3) This actually depends on whether or not your spool holders will be hung from the under-shelf mount or sideways via the wall mount. If you hang them you'll want things tighter than if you hang them sideways from the wall (because the weight of the spool will be pressing down on the clutch, pushing it into the Hang Collar). As far as wiggle room on the shaft... That shouldn't matter much at all, really. The spool will be tight against the two collets and if the bearings wiggle around a bit on your metal threaded rod that shouldn't impact anything (I mean, unless they're ridiculously loose but even then I have my doubts =).

If you're using a retractable badge holder with the vertical mount you'll need to clamp that sucker down (or screw it in/glue it) somehow. The tension added by the badge holder will be enough to lift it slightly and move it all around. The vertical stand is really meant for "just the clutch". I should add a note about that somewhere...

Yeah, I think I ended up with larger pun nuts. I had a set of regular M8 and M8 lock nuts, and both of those come in at 12.8mm wide. My 5/16ths came in at 11.8mm, but I also had a larger set of 5/16 that were 12.5mm. So guess they aren't entirely consistent on external dimensions. I'll stick with 5/16 for now since it is working.

On the badge holder, I may modify the holder so that I can place some M5 nuts on the top portion and can screw up to it from inside the enclosure. That would help hold it down. The wall mount is held in there pretty well, just need something to help keep it on the ground.

In the future when my MMU2 finally ships, I'll likely add some wall mount ones, however didn't go that route for now because it'd be longer bowden tube to get the filament in front of the frame on the MK3.

Thanks for your help!

Oh, and I forgot... Kerberos is kind of a beast. But I'm more of a visual person, so it made much more sense how things fit together when I opened up the scad files and uncommented the diagram where everything was mapped out.

Oh I'm glad someone actually found that useful! I was worried that having such a big chunk of code commented out (right near the top) would just leave people confused.

...and yeah, Kerberos is so damned complicated I say, "it's not Kerberos" instead of, "it's not rocket science" because rocket science is pretty straightforward these days (thanks to having already discovered the necessary math and... computers) =)

Hi, Could you please tell m where the tensioner file is? I don't want to use the badge rewinder type. Thanks

The tension is controlled by tightening or loosening the (M8) nuts on either end of the center shaft. There's a "2x_Tension_Knob.stl" that makes this easier (don't need to get a wrench). Basically you get the tension where you want it and then tighten down a second nut above (or below depending on the orientation) the nut controlling the tension in order to lock it into place (so it doesn't unscrew itself).

So just print the clutch instead of the spring or the retractable ID badge rewind mechanism.