Thanks for you thoughts on this Chrissi.
That is a lot harder to do I think. I will take a look at an alternative
design. This is what Hoffman and MT do. Ivo does it differently. (On the shaft.)
None have the solenoid engagement that this design does so the brushes
are always in contact. In our case the brushes only contact the slip
rings for seconds. Only when changing pitch. It is not a constant speed
prop that would require the brushes to be in contact all of the time.

Paul Lamar

It would be a different product but machining a port in the side of the tail of the redrive for the wiper cartrige and putting the ring on the shaft inside the oil bath would be next to ideal. If the contacts were bifrucated well enough they should easily maintian the signal and last a whole lot longer without the dirt contamination. The shaft itself would require a tiny hole down the center for the signal wire. yeah I know, way too complex.
...Chrissi
Cozy Mk-IV 13B-turbo
www.CozyGirrrl.com

I think you are missing something Chrissi. These brushes are going to get wear that
is 1/1000 of the wear of say a Hoffman or MT electric prop brushes. In some cases
they are only engaged for seconds on any given flight. Take off and climb at
low pitch. Increase the pitch for cruise. Decrease the pitch for landing
and you are done using the brushes.

For contrast here is a drawing of the MT brushes and complete electric prop.

Paul Lamar
 
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