Choices of Winder and Digital Torque Meter

[Tom-TTom2015]

Hello Coaches- Happy New Year!

1. We kept hearing the choices over K&P winder 10:1 and 15:1. Actually during the practice, we felt like that we’d like a 15:1 or even 20:1 winder which would handle the rubber as robust as K&P 10:1 winder. Do we have such a choice available?

2. Also, we kept hearing the peak torque could be higher than 2.25 in-oz, which could be a challenge for the 2.0 in-oz wire based torque meter, especially after repeated uses. We are then wondering what’s the choice for a reliable digital torque meter?

Many thanks

[coachchuckaahs]

As far as winder, the Heli rubber is getting 1000-1500 winds, which is not hard to do with the 10:1 winder. If you go to 15:1 or 20:1, you can wind faster, but it may get hard to turn the crank at 2.25 oz-in output. Also, the 10:1 affords a better feel of the rubber, in my opinion.

As far as teh KP winder, this is available as 10:1 and 15:1. I believe 15:1 has a blue tip. A similar orange winder is available from AMA (and other sources) that is 20:1 (also at IFFS, https://www.indoorffsupply.com/shop/201-winder). Again, for high torque applications I would recommend staying at 10:1.

For digital torque meter, the only current commercial one as far as I know is from Indoor Free Flight Supply, https://www.indoorffsupply.com/shop/iff ... rque-meter.

You can also build your own from my Thingiverse design, https://www.thingiverse.com/thing:4241753

As far as wire TM's, most of these have either 0.020" and 0.015" wires, which will probably deform even below 2.0 oz-in. You could build your own using the NFFS guide for "super simple torque meter" at https://www.freeflight.org/science-olym ... resources/. If you use a 0.025" wire (check Ace Hardware, local hobby shop, Do It Best hardware), then 12" of active length will give 3oz-in in about 295 degrees of rotation. You would make a clock face with each oz-in 98.3 degrees apart. This is approximate, depending on the actual diameter of your wire as well as the elastic modulus of your wire. But it should be close enough for repeatable work within your team efforts. Note that the stiffness (rotational) of the wire goes with d^4, so this is quite sensitive to wire diameter. The 0.025" wire shoul dbe safe 9not plastically deform) at 3.0 oz-in.

Coach Chuck