Re: Rubber testing - some info

From: <mkirda_at_sbcglobal.net>
Date: Wed, 14 Nov 2012 23:23:18 -0000

Tapio apparently did an article in this year's NFFS symposium on 'Practical Rubber testing'. I don't have it yet. I'm sure Jeff used a formula from somewhere - maybe he can chime in.

I will search the INAV archives tonight to see what is there...

Regards.
Mike Kirda

--- In Indoor_Construction_at_yahoogroups.com, "joemargbartek" <j.bartek@...> wrote:
>
> Mike
> Has a reference been posted to the formula Jeff uses to get energy? Is it in a particular issue of INAV?
>
> Joe
>
> --- In Indoor_Construction_at_yahoogroups.com, "mkirda@" <mkirda@> wrote:
> >
> > Greetings.
> >
> > Jeff Annis sent me the spreadsheet he uses for computing the energy level of rubber.
> >
> > After some false starts, I have learned a few things.
> >
> > 1) Three of the four batches of rubber are nearly the same at near 4000.
> > 2) 6/12 Tan SS is the worst at 3400 at best.
> > 3) A second wind immediately after the first may get you 200 more turns, but energy return is significantly (15%) less. With the Tan SS I have, you really run the risk of breaking the motor - which somewhat explains the problems I had earlier I thought were related to the o-rings I was using.
> >
> > I have been winding ~.054" motors to .55 or so in-oz of Torque, then unwinding 20 turns at first, then 50, sometimes up to 100. After unwinding, it takes some time for the torque meter to steady. A light thump on the rubber seems to make is stabilize quickly. A lot of data points are involved.
> >
> > I'll probably share the data after I compile some more.
> >
> > Regards.
> > Mike Kirda
> >
>
Received on Wed Nov 14 2012 - 15:23:21 CET