On Wed, 17 May 2017 08:17:42 -0500, DougC
wrote:

On 5/10/2017 9:56 PM, sms wrote:
On 5/10/2017 5:44 PM, DougC wrote:

snip

I can make mounts too but don't really wanna.

Yeah, I make mounts. Not because I really wanna, but because I can make
mounts that are a lot better than what is commercially available. I use
the Maglite Delrin clamps on a piece of aluminum flat bar mounted to an
aluminum or steel clamp for the bars.

Well it looks like I'll be making mounts after all.
The most-capable-looking ones on Amazon don't look like they're going to
do too well here.

Try this Google image search to see what's available in aluminum:
https://www.google.com/search?tbm=isch&q=+aluminum+bicycle+handlebar+head light+clamps
I don't think plastic is strong enough unless you reinforce it with
metal inserts. If it can be tightened by hand, it can be done better
with a tool. That leaves aluminum clamps, which methinks will work
the best.

One possible problem is the rubber cushion often inserted between the
clamp and the handlebar. Often, it's rather thick to deal with the
difference between 25.4, 26.0, and 31.8mm diameter bars. With a thick
rubber shim, you'll never get it tight enough to keep it in place and
not vibrate. Therefore cut the aluminum clamp for the correct size
handlebars and use a minimally thin sheet of rubber or plastic.

Another purpose of the rubber shim is to prevent the clamp from
gouging the handlebar. This is a typical case of the design causing a
problem that is somewhat fixed with a rubber band-aid. For example,
the teeth in this crude abomination:
https://img.banggood.com/thumb/water/oaupload/banggood/images/6A/5A/6c3c7474-dbda-4588-9aa3-d5783d8df954.jpg
are guaranteed to gouge your handlebars, no matter what you use for a
rubber shim. It will rotate, because the entire contact area is in
the tips of the serrations. To get a good grip, they should have
designed for more surface area, which means no teeth. Teeth work only
if the mating surface also has teeth or matching serrations, such as
in a stem to handlebar clamp. For mating with the flat surface of a
handlebar, you want another flat surface.

Some random ideas:
1. Make the clamp symmetrical so that you can simultaneously mount
something both on top and on the bottom of the clamp assembly.
2. If you're going to remove and reinstall the clamp often, don't
thread the aluminum. Use steel PEM inserts instead, which should last
longer.
3. If you want security, design it to be either very easy to be
removed, or a nightmare of exotic and inaccessible screws.
http://atomic22.com
https://www.bicyclebolts.com
4. Test the clamps grip with a simple torque tester to see if it
meets your expectations. Attach a stiff arm and tension scale to the
clamp. Pull and calculate the torque (ft-lbs or Newton-meters) where
the clamp starts to slip. Compare with other clamps.

Good luck.



--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558