friction torque

by bill martin in 912 / 914 Technical Questions 13 years ago

Roger,

I've looked at calculations till my brain is fuzzy. Please help. I'm trying to measure the friction torque of my slipper clutch with a set of scales that measures in lbs. If I measure out two feet on the prop and pull from that point with the scales, I calculate I should measure between 11 to 22 lbs on the scales. Does this sound right?

Bill.

Re: friction torque

by Roger Lee » 13 years ago

Roger Lee

128 5.28k 4.98k

Hi Bill,

You are correct. You can measure any where from 24 - 30 inches out from the center of the prop hub. Put your handy dandy fish scale on that mark and make a nice steady pull until the prop stops noting all the time what the lbs. reading on the scale as you pull. I usually do it 2-3 time to double check. The reason not to go lower than 24" for me is that the closer to the hub the harder it is to have a nice steady smooth pull. Once you get your lb. from the scale then multiply that by the number of inches you measured out from the prop center.

Example.
You measured 26" from the prop hub center.
Your reading on the scale was 18 ft/lbs.

26" X 18 ft/lbs = 468 in/lbs of slipper clutch torque. This should be done at every 100 hr. inspection and or the annual.

The range is 264 in/lbs to 532 in/lbs and the higher the better. Normal seems to be anywhere from 420-480 in/lbs with 460 average.

Roger Lee
LSRM-A & Rotax Instructor & Rotax IRC
Tucson, AZ Ryan Airfield (KRYN)
520-349-7056 Cell

Report

You do not have permissions to reply to this topic.

Title	Category	Replies
Torque 912 ULS	912 / 914 Technical Questions	7
General Torque Values	General Tech Discussion	2
Engine attach bolts - torque	912 / 914 Technical Questions	4
912 ULS Crankshaft Nut Torque Question	912 / 914 Technical Questions	12
582 Engine Block Bolt Torque	2 Stroke Technical Questions	3

friction torque

Recent Videos

Safety First!

Prize Giveaway!

Log In/Out

Login