Woodruff key for pony motor flywheel

Hi Fred , I have a D68U pilotmotor in pieces at the moment and have the key here in my hand .
Now , I am not sure if US inches are the same as our inches ,But here goes ,Lenght is one and a half inches .
Width is three eigths of an inch .
Depth is five eights of an inch .
Hope that helps .

Hi Fred,
Last summer I needed a key for the pony flywheel on my D6 9U...Cat dealer told me that these were not available...I ended up making my own. I wrote down the dimensions of the key and the numbers ianoz gave you are right.

Johnstone

Sorry you didn't get that, Fred. If you are not in a big hurry I can look for it and send it to you. Joel

You really need the length of the key as well as the width and depth. Almost all woodruff keys are a section of a circle. The radius can be quite different in keys that are the same depth and width. The length also helps you get the distance it should stick up above the shaft correct.

Should be able to get some modeling clay or even just clay from the ground and make a mold of it to get the dimensions right. I have made them from flat stock the right thickness or have sawed them off the end of a shaft if I had one the right diameter handy.

According to The Machinest Guide, a woodruff key by definition is roundled similar to a half moon shape. A straight key is called just that or in some circles a shear key. Now I am curious if the 9U pony has a woodruff key or if it is a straight key. I assumed straight by the dimensions given.

Hi Team,
the 5R D6 ponies had straight keys (4B2625, hard key, 1 15/16"l, and 3/8" sq)
The U D6's have woodruff keys (5F8454 - likely hard key steel)
The part # in my old NPR Similar Parts List shows a standard key of the dimensions ianoz gave ( 1.5" long, 3/8" wide and 5/8" deep) as being a 1B8741 (likely soft key steel) this would be an industry standard size "G" key of dimensions, by Newnes, 1.5" long, 0.376"w and 0.376"D.

I stand to be corrected on the above but, I seem to recall the flywheel keys being difficult to file.

Hope this helps,
Cheers,
Eddie B.

Hi Team,
the 5R D6 ponies had straight keys (4B2625, hard key, 1 15/16"l, and 3/8" sq)
The U D6's have woodruff keys (5F8454 - likely hard key steel)
The part # in my old NPR Similar Parts List shows a standard key of the dimensions ianoz gave ( 1.5" long, 3/8" wide and 5/8" deep) as being a 1B8741 (likely soft key steel) this would be an industry standard size "G" key of dimensions, by Newnes, 1.5" long, 0.376"w and 0.376"D.

I stand to be corrected on the above but, I seem to recall the flywheel keys being difficult to file.

Hope this helps,
Cheers,
Eddie B.