I went to Kaman Industrial Technologies about 4 weeks ago hoping to find some NEW needle bearings for
my planet gears. We found something very close, but one was in inches and my needle bearing I suspect are
in metric, all the fasteners are for the trans. They were kind enough to wait until they had a minimum order
from the supplier and then they ordered just 20 needles at $10. Well they finally came in so I went picked
them up hoping I found a supplier for new bearings.
I measured them with my ball micrometer, which is not the right instrument, but with a little patients I figured
I could get a accurate dimension to within a couple of tenths. I measured many times and the largest number
would be the most accurate if you consider the geometry of the spherical ends on the micrometer and the shape
of the the bearings....... think about it !!!
Well I could not tell that there was any difference in the bearing diameters, they all seemed to be in the
neighborhood of .07695 for both the Kaman and OEM needle bearings. The last digit is for rounding and
only shows .00000 or .00005.
Now the reality ...... I could only get 18 new bearings inside the planet gear, where the OEM bearings required 19. I
know this is not scientific, but they don't feel any different when you check for radial play, but it's how you inspect
the planets when rebuilding the trans. I also put the axle in place and tried moving the axle at the farther point from
the gear and it still felt the same. Doing it this way magnifies any play by the distance the axle extends beyond the
gear. Picture if you will, the axle is 2 feet long, any play would be very noticeable since it would move many times the
distance of the original axle.
I believe it come down to a very very small difference, probably in the area of one tenth or .0001 per needle. When you
consider the diameter difference of one needle times 18, then it becomes a very noticeable difference of .0018 or almost
two thousands of an inch.
Now at this time I don't have to risk using them, but it's a very interesting problem.
Now this is where you guys come in .... will it work ???
Anybody need me to build a 200-4R for them, I need to do some testing.
PM me with your PayPal account so we can get started !!!
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