Print a thin, flexible band?

I do not have a 3D printer or access to one, but I'd like to ask some questions to see if this is possible.

I have an application where I need a small, thin, flexible band that will fit around a .5" pipe.
The band should be about 11mm wide and wrap around the pipe and connect to itself snugly, so that it isn't accidently moved.

The band should be flexible enough to wrap around the pipe and onto itself, slightly stretchable so it can be pulled
tight and secured to itself and stay in place, yet have the stiffness to be moved slightly up/down on the pipe using fingers/fingernails to adjust.
It should also not scratch or mar the pipe.

I currently use electrical tape for this, I cut a length and wrap it around the pipe twice. But adjusting means unwrapping the tape,
slightly moving it, and re-wrapping. This leaves adhesive on the pipe as well as eventually makes the tape not stick to itself anymore.
Not to mention if the pipe gets hot, the tape slips.

I'm hoping for a solution where I can have a band that stays on the pipe through it's own pressure and is stiff enough to be adjusted.

I experimented with various non-adhesive rubber and silicon tapes. They were too thick and when I tried to adjust them on the pipe by using my fingernails to slide them up/down they folded over
on themselves.

Is there a material that fits these qualities that is printable?
Or another source? It doesn't have to be printable, I'll cut the shape I need out of a sheet of material if I need to.. Just can't think of what this magic material could be..

An O-ring?

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

A rubber O-Ring or rubber band sounds ideal, or maybe you could get some inspiration from this "Flexible Bracelet" on Thingiverse:
[www.thingiverse.com]

I've printed a few of these out of PLA, and they're surprisingly flexible and robust; I imagine they would be even tougher and durable if printed in ABS.

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Follow my Mendel Prusa build here: [julianh72.blogspot.com]

If you don't have access to the ends of the pipe, then try a layer of HDPE or other plastic under the tape Vinyl electrical tape will get soft when heated, so it wouldn't be my first choice.

Edited 1 time(s). Last edit at 11/10/2015 02:11AM by etfrench.

A reusable cable zip tie maybe. Something like this can take care of the rubber band problem.

I've printed a belt for an old MSX-2 floppy disk drive using flex filament, which is poly urethane. It's very slightly stretchy and flexible. It's also very strong, even at a width of 0.5mm 6mm high. At 11mm it would be even stronger. It's slightly rubbery, so it should keep whatever you want to use it for in place but is easy enough to move. I think it's also stiff enough that you can't roll it on its own axis. Seems to be perfect for what you want to do.

It can be challenging to print though. I print it at 250 degrees C so make sure your hot end is all metal, print speed at about 30mm/s max. Any faster and it will cut corners and pull the whole object in on itself as it cools slowly and stays soft. It also is stringy so be prepared for some cleanup. If you use bowden there's some blobbing too on layer changes and retractions. I've been able to sand away the blobs and the belt fits well and the 30 year old disk drive works again!

@imqqmi: I don't mean to hijack the thread and maybe it would even help the OP so could you post a picture of it? Maybe you have a picture when printing or maybe there is a blog documenting the process?

Thanks.

Edited 1 time(s). Last edit at 11/12/2015 01:25PM by realthor.

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@realthor: I took pictures and videos while printing the belt, I can put up a page to share the process of replacing the belt. I'll try find some time this weekend and report back here. I always intended to blog about my 3D printing experiences but haven't got around to it to do it. Thank you for your interest, it certainly helps to publish some of the material I've collected. Frankly there's too much of it, I get a little daunted

@imqqmi: Are you kidding? Printing belts is one of the holy grails of 3D printing, along fiber-reinforced resin SLA printing of gears and maybe ceramic laser sintering for bearings .

Jocking aside, I've seen 3D printed belts since 2013 (3D Printed 83T GT2 Timing Belt) and 2014 (Zen Toolworks Flexible Filament 3D Printed Timing Belt) but I wonder how much did the process and quality evolved, considering that we now have some good filaments for this process.

The timing belts created by industrial processes are usually made of Aramid (like Kevlar) tensile cords, Nylon teeth and Polyurethane backing. We can already print in Nylon but I don't know about the polyurethane -Wikipedia says there are thermoplastic polyurethanes.

Maybe the best is to open a new thread where the community can chime in and develop a process. I know timing belts are cheap as peanuts when bought from China but with 3D printing you can adapt the closed loops to your specific lenghts, making it a customization process rather than cutting and clamping belts from a roll. There are other ethical and environmental concerns too with buying from shaddy sources but let's stop here.

Let us know where do you decide to present your work.

Edited 1 time(s). Last edit at 11/12/2015 07:32PM by realthor.

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RepRap Lander concept on Concept Forge
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My Things, mostly experimental stuff

Creating my own belt and making it work was really quite satisfying for sure. Calculating the length was tricky but doable. Cheap 2.5 belts that came with the i3 kit is reinforced with copper wire. It's a bit stretchy which is bad if you don't want to tighten the belts every day. I bought a high quality closed belt made of steel wire reinforced clear polyurethane which said it didn't need to be broken in, it doesn't stretch at all. It is relatively expensive though, at about 25 euros for a 931mm length belt compared to a couple of euros per meter for regular belts.

I've seen teethed belts on thingiverse but never printed one. The one I printed is not teethed, so it's as simple as they come you'll probably need a 0.25mm nozzle to print those.

The disadvantage of diy printed toothed belts is you can't reinforce them, but i guess it's possible to combine poly urethane and nylon with a dual extruder.

I have some ideas about reinforcing 3D printed belts with Spectra and I am aching for some time and a 3D printer where I can experiment. I have designed a printer with Spectra for all motion transmission just because this was the goal i've set at the begining ("no belts until we can reliably print them") and it was a pain. Spectra can be broken-in (pre-creeped) before using it by hanging a weight of its ends of close to the force it will take in operation and leaving it there for a week.

Basically you still have the spectra coil but this time it is there only to keep tension, inserted in some helical grooves on the back of the belt. I am wary about it cutting through the nylon though and not many ideas about how to tension it after you've made the knot. I think I can easily design that in CAD and it's definitely doable.

And why need .25 for printing it. it's not the tiniest thing in this world to print?

Edited 4 time(s). Last edit at 11/13/2015 03:56AM by realthor.

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RepRap Lander concept on Concept Forge
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I've setup a blog website describing printing the flex belt I've mentioned earlier. Please let me know what you think!
Pringing with flex filament

Edited 2 time(s). Last edit at 11/15/2015 01:04PM by imqqmi.

Quote
imqqmi
I've setup a blog website describing printing the flex belt I've mentioned earlier. Please let me know what you think!

Hmmm, link?

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RepRap Lander concept on Concept Forge
RepRap Lander concept on RepRap Forums
My Things, mostly experimental stuff

Sorry, I've updated the post above!

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Kind regards
Imqqmi

NFAN CoreXY printer:
[reprap.org]