Jim:
There are varous O-rings you can use. I am only familiar with the
types used on Science Olympiad planes, that typically use a 2 gram
rubber motor. So the O-rings can be made of Nylon - just cut off a
section of small tubing. Some cut off part of a ink pen cartridge, for
example. Generally you don't want the weight to be more than about .02
grams per O-ring. This is because in Science Olympiad, they count the O-
rings too see if you exceed the 2 gram maximum motor size. .02 grams is
plenty strong enough.
The diameter of the O-ring has to be big enough to easily fit over the
motor hook but not hit the motor stick. I think about 5 mm OD is good.
About 1 -2 mm in axial thickness should be fine. Some of the experts
may want to comment on the dimensions. I am just looking at a ruler
and approximating what we have used successfully in the past.
Some people use fancy synthetic rubber O-rings like Buta N (spelling?)
that are widely used as seals. I think some of these come in the Ray
Harlan kits. If you don't want to make the the Nylon O-rings yourself,
I think Lew Gitlow of Indoor Model Supply in Florence, Oregon sells
them very cheap. Try to get his book on indoor model building if you
can - he is a master builder/flyer and there are many great tips in his
book.
Calgoddard
Received on Tue Dec 05 2006 - 19:16:47 CET
This archive was generated by Yannick on Sat Dec 14 2019 - 19:13:44 CET