Mark L wrote:
I'd run it off the crank end, where the power was meant to be
> delivered. If you're going to design something to take the gyroscopic
loads
> anyway, I'd fasten it to the other end of the crank...
Hi Mark
Thanks for the reply, I was unaware of any failures of the type IV crank at
all. I was led to believe that it was a very strong crank which if done
properly would handle a lot of punishment. Even the failures mentioned
earlier only spoke of the welded hub failing.
I have considdered driving the prop from the flywheel end but cannot come up
with a way of handling the thrust bearing issue without adding a bunch of
unwanted extra weight.
As a matter of interest I am getting a scrap crank from a local VW repairer
and am going to conduct a test to see just how much torque the standard
taper will handle before failing. I am first going to use some grinding
paste to lap the taper surfaces for a perfect match, put it together with
locktite and preheat the hub for a slight shrink fit on the crank.For this
test I will be using a welded flange to the pulley hub with a long lever arm
bolted to it.
My guess is that for every broken crank out there, there are at least twenty
that have been working fine for many hours.There was probably a very good
reason for them breaking as well. I personally know of four KRs here that
have used that system and have flown many hours. I must concede that they
all use the longer taper as in the force 1 hub (unsupported)
If you could find that info I would appreciate it.
Phew, over and out
Cheers
dene.coll...@telkomsa.net
