On 2/22/2012 6:57 PM, Jim Wilkins wrote:
wrote in message
...
"Jim Wilkins" wrote in message ...

wrote...

I'm wanting to make a display for load cells, ...
Anyone here done anything like this? RogerN

...
Another idea is to use a snatch block or pulley (wire?)rope to
expand the scale of the lighter duty scale.

I made a 2x two-wheel block and tackle to raise my TV antenna, with
well-greased Oilite bushings. The ratio between the raising and
lowering rope tension is over two to one because of pulley bearing
friction. A pulley arrangement might be acceptable with needle
bearings but they are a lot of work to make, and waste if it isn't.

A dial scale is relatively safe if its hanging, but not when it's part
of a horizontal or angled pull unless you set up a table or such to
support the scale and the heavy pulling devices while you are hooking
up and taking in the catenary slack.

I wouldn't put anything that wasn't simple, rugged and foolproof in
line with a long cable under heavy tension and then stand next to it.
Once a cable eye clamp I was testing let go and dumped all my gear
hard on the ground, knocking the crystal off the Dillon's dial
indicator. For testing I now place the equipment on card tables and
connect it between two big trees. There are tow straps loosely
attached to the gear to prevent it from whipping in my direction if it
breaks.

jsw



they make a little tension guide for tuning sailboat rigging (so you can
get the mast in column straight). pretty cheap, sort of like a spring
scale on a simple piece of sheet metal.