flyrotary@lancaironline.net Mailing List Archive

Tracy,

I do have access (if $ufficiently bribed) to an experienced machinist, with a Bridgeport that should be able to handle the job. What’s the chance of getting an output shaft pre-drilled with ¾” bushing holes?

Mark S.

(lawn ornament comment referred to the M/T prop.)

From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Tracy Crook
Sent: Wednesday, December 15, 2004 12:16 PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: M/T Prop Won't Fit PSRU

I have no objection to removing the 5/8" drive lugs and drilling out the prop flange hole for 3/4" bushings. I'm just saying it probably can't be done with a hand drill in the garage. Any good machine shop would be able to do this with the required precision.

Tracy (cringing at the thought of RD-1C lawn ornaments)

----- Original Message -----

From: Mark R Steitle

To: Rotary motors in aircraft

Sent: Wednesday, December 15, 2004 12:37 PM

Subject: [FlyRotary] M/T Prop Won't Fit PSRU

I have been working to resolve a problem for more than a month now and thought I would query the group for a possible solution.

If anyone else is running (or planning to run) a 3-blade M/T electric prop with the RD-2C gearbox, I have discovered a mating problem in using this prop/gearbox combination for my 20B. The problem is the RD-2C prop flange comes with 3/8 id x 5/8 od bushings. The M/T prop has a stepped hole that is ¾” for the first 3/32” and then goes to 5/8”. Tracy is not comfortable with drilling out the 5/8” bushings and M/T adamantly advises against using anything less than ½” prop bolts with this prop. So, I’m at a standstill until I can get this resolved. The only solution I can see is to press out the existing bushings and open up the holes to accept ¾” od x ½” id bushings. But that would require disassembly of the gearbox and some precision machine work, possible but not my first choice.

Mark S.

Lancair ES – 20B

(with a very pricey lawn ornament)