Rubber Bands

A project log for Antigravity Arm Floats

Wheelchair mounted orthoses to enable someone with very low muscle tone to move her arms without the encumbrances of gravity

mike-turveyMike Turvey 10/10/2016 at 04:343 Comments

An ongoing problem I've been running into is that run-of-the-mill rubber bands wear out surprisingly quickly. After a month or so of use, they start breaking down, showing minor cracks, and finally breaking. Stored rubber bands certainly don't break down so quickly (they last for years in my cupboard). I'm guessing that the big difference is light? UV radiation certainly could be attacking them and causing the wear patterns. Perhaps being under constant stress also plays a meaningful role?

Regardless of the cause, I'd really like to find a better rubber band. I'm thinking that some sort of a silicone band would be ideal. But, the only silicone bands I've been able to find are intended for use in the kitchen, and as such are much too big and pretty expensive. If anyone has a better idea or suggestion, I'm all ears.


Mike Turvey wrote 10/21/2016 at 20:03 point

Thanks for the good suggestions.  I just ordered a pack of 2-inch silicone cooking bands-- basically silicone rubber bands made for use in an oven or on a grill.  I'm optimistic that they'll hold up a lot better-- I'll report back here how well they work.

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K.C. Lee wrote 10/21/2016 at 15:49 point


>Reaction of the rubber polymer, either at the double bond or at the allylic hydrogens, with ozone or oxygen or other oxidizing agents results in breaking the polymer chain. This weakens the bulk material and with time destroys the material. This weakening is noticeable in rubber articles such as rubberbands that have been around a while and have become brittle and cracked and have lost their ability to stretch.

Might want to look into "tension coil springs".

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ford.anthonyj wrote 10/21/2016 at 15:31 point

Awesome project! I'm glad you've been able to make such a difference in your child's life!

Regarding the rubber bands, have you considered silicone o-rings? Or possibly Latex tubing, like the old school surgical tubing might work.

My last idea is slingshot tubing (which is usually latex tube anyways) is relatively inexpensive. 10ft for $5

You might have to come up with a joint piece though, since this tubing won't be a continuous loop like a rubber band. 

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