pic: 3280 Tape Measure Hanging Mechanism

[GeeTwo]

Originally Posted by Knufire

Thirded.

I haven't done one of these myself so I may be completely wrong, but this is what I understand between what I've read and in attempting a tape measure potentiometer last year:

Tape measure rules are flat sheets of (essentially always) steel. These sheets are rolled onto the axle inside the tape measure unit in a flat configuration where they bend quite easily, but are bent a few degrees (typically about 10 or 15) as they leave the tape measure through a curve molded into the case so as to provide stiffness against the tape buckling. Stanley Fat Max appears to be the best on the market at this function.

Tape measures are meant to be pulled, not pushed. The challenge then becomes one of driving the unrooling of the spool at the shaft end before the curvature is added, or driving the tape after it is curved without ruining that curvature (this should be easy for teams who can sculpt a wheel's profile on a lathe).

[s_forbes]

Originally Posted by GeeTwo

Tape measures are meant to be pulled, not pushed. The challenge then becomes one of driving the unrooling of the spool at the shaft end before the curvature is added, or driving the tape after it is curved without ruining that curvature (this should be easy for teams who can sculpt a wheel's profile on a lathe).

If you push fast enough, they don't seem to care.

https://www.youtube.com/watch?v=rNyMEM3njrM
http://www.youtube.com/watch?v=qJFQkBGCgaE&t=0m19s

This mechanism just ran a 1.625" rubber Banebots wheel against a tape measure. It was flat at the drive wheel, but had a long support that allowed the tape to curl back up.