YES, and it does work.
W1CW built, and we have had installed for almost a decade now, a coupler
based on the BMW flex disk... I bought ut from the local BMW dealer for
about 50 bucks - believe the car it is for is a 50005 (that info is in
Leason's book)... tried to find an equal from a generic source but no
luck... ended up having to get the mil-spec version :-)
The rubber flex disk used was approx. 1 1/2" "thick" and had metal
sleeves running through it - 8 I believe...
As my father installed it - it was used with a Create RC5B3, and has
been in service since at the top of our highest tower.
The doughnut has half its metal sleeves bolted to a plate which is
attached to the lower half of the mast to rotor clamp... and the other
four bolts went up to a plate which anchored to the upper half of the
mast to rotor clamp... the plates have voids on the far side of the
active or bolted to space so that should it give under start/stop/wind
stress the bolt head does not hit against the other plate (seem to
remember the holes were made big enough that a socket could fit through
them for tightening of the sleeve against the far plate.
The only problems this rotor has suffered are electrical (this is FL) -
mechanical... note - although the load on it has been small so farm,
thus far never has a consideration of mebbe this was a bad idea popped up!
Somewhere in my archives I have color photos of the assembly - should I
ever find them I will scan them on the flatbed and make them available
via e-mail attachment to those who are interested...Dad did a great job
If it weren't 135 foot up in the air I would take a photo of it in place
Dennis Mowers wrote:
> Has anyone built the shock absorbing mast coupler described in Leeson's
> "Physical Design of Yagi Antennas"?
> He describes a BMW "flex disc", used to isolate the drive shaft from the
> My local NAPA auto parts supplier shows nothing in their books for any
> year BMW.
> I will try BMW next.
> Has anyone ever seen one of these things?
> Dennis, K5YA
> Self Supporting Towers, Wireless Weather Stations, see web site:
> Call 888-333-9041 to place your order, mention you saw this ad and take an
> additional 5 percent off
> any weather station price.
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