On Mar 11, 10:35 am, Tim Wescott wrote:
More design questions:

I need a stick-like thing, about 30 inches long, to go from a pivot
point to a little electric motor. It needs to be moderately rigid,
light and inexpensive in lots of 50 each or so. It would also be quite
nice if it's moderately attractive -- mill finish aluminum without too
many scuff marks is just fine for this. Prettier is better.

I'm thinking that thin-wall aluminum* tube of about 5/8" diameter will
work well, and I'm getting ready to be shocked once again by how much
things cost these days. While I'm waiting for quotes, I thought I'd
solicit the group for suggestions.

Fiberglass? Carbon fiber? Phenolic? Other plastics? Titanium**?
Extra thin-wall steel? Balsa wood comes to mind, but while it is low
tech I suspect it'll cost more than aluminum. Cooked spaghetti is too
limp, and uncooked is too brittle.

Anyone have suggestions? Do you have supplier names to go with your
suggestions?

* Alloy isn't terribly important. Even dead soft would work, although
harder would be better.

** OK, maybe it's more expensive than aluminum.

--

Tim Wescott
Wescott Design Serviceshttp://www.wescottdesign.com

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Hi, Tim.
Should I say "here we go again!"? First, how will it be fastened to
your device? Will it be twisted, pushed or pulled? Will it matter if
it is solid or must it be a tube?

The first thing that comes to mind is using a piece of the white resin
electric fence post available in your local farm store. These are
either 3 or 4 ft. long and about 1/2 inch or perhaps 3/8 inch in
diameter. We cut pieces off to use in a customer's product. I am not
sure of what it is used for, but sometimes I am sent to buy another
stick or two. They are quite stiff, but light.

If you want to look at carbon fiber tubes or fiberglass tubes, go
check out an archery store. They have both for the local arrow makers.
They might even cut them to the length you need.

The most critical factor with tube is crushing it when you make
attachments.


Good luck!

Paul Drahn, President
Jodeco, Inc.
Redmond, OR