Hello Carl, I've just joined the forum and found this email interesting.
When I first got into indoor it was in Tampa where I met Dick Obarski who
was an ole timer in indoor, you may have known him or heard of him. He took
me under his wing and became my mentor. He was in the middle of testing
rubber and was going through the stretching ( using a scale to measure
pounds of pull) as u stated. He would stretch a certain distance, measure ,
let the rubber rest then re-stretch at a greater distance and measure etc.
He would do this until he would come up with a value. However , this was so
long ago I forgot his procedure!!!
Ed Berton
-------Original Message-------
From: Carl Bakay
Date: 2/28/2011 2:02:51 PM
To: Indoor_Construction_at_yahoogroups.com
Subject: Re: [Indoor_Construction] Re: Rubber Motor O rings
I have done a lot of rubber testing thanks to Goldstein's prodding during my
INAV days, testing mostLy 7 inch loops of 1/8 strip, and without exception,
those that broke did so at the knot. These knots were un lubricated, due to
the difficulty of tying a lubed knot. The stye of the knot did not matter ..
It seemed that that was where all of the stress was located.
I wrapped my loops for stretch testing around a nail, over which was slid a
piece of Tygon fuel tubing. This also allowed the knot to move, in keeping
with current FAC technology for short rubber motors in multiple-engine
planes.
Carl Bakay
Sent from my iPad
On Feb 28, 2011, at 12:46 PM, "dennisatyson" <ddtyson_at_peoplepc.com> wrote:
Here is another source for 90A durometer o-rings at a great price.
http://www.oringsandmore.com/servlet/StoreFront
--- In Indoor_Construction_at_yahoogroups.com, Warthodson_at_... wrote:
>
>
> From what I have read & experienced, o-rings cut from plastic tubing do
not cut into the rubber any more than the wire hooks. It seems counter
intuitive, but many very experienced indoor flyers use plastic tubing for
o-rings. Personally, I prefer the hard plastic o-ring to a rubber o-ring. I
find them easier to hook up. I read somewhere that someone boiled their
plastic o-rings to remove the sharp edges, but I have never met anyone that
told me they actually do that. If the sharp edge were cutting into the
rubber I would expect most of my motors to break at the o-ring, but again
that has not been my experience.
> Gary
>
>
>
>
>
>
> -----Original Message-----
> From: Terry <jantel98_at_...>
> To: Indoor_Construction_at_yahoogroups.com
> Sent: Mon, Feb 28, 2011 7:05 am
> Subject: [Indoor_Construction] Rubber Motor O rings
>
>
>
>
> What are people using for O rings ?, I have heard of rigid plastic being
used, if so do it not cut into and damage the rubber ?, I have just cut some
thing rings from a light plastic (Ear cleaner) tube and was looking for a
way to smooth them down a little
>
> Terry
>
- application/x-ygp-stripped attachment: stored
- application/x-ygp-stripped attachment: stored
Received on Mon Feb 28 2011 - 13:14:41 CET