Difficulty fitting spinner after prop repair

[Ralph Inkster]

That post was so long ago, I couldn't remember my reasoning...
I've r&r'd probably 8 props for overhaul & Murphy with out fail positions the 6 spinner holes just that bit out of phase, close enough that I wouldn't be able to drill new holes & install nutplates in the bulkhead My solution as described is to reposition the front bulkhead so I have lots of virgin flange to drill new holes & nutplates.
As for elongating the 4 center mount holes, I've seen the damage from cracked spinner bulkheads... cost a set of blades on one plane.

[von_flyer]

Just went through this a couple months ago when I had the prop seals replaced and blades refinished. They stated the clocking of the front threaded holes may be different since they tighten the 'nut' to a torque and not a position. They showed me a Mooney front plate that has a large amount of rotation allowed by slotting the holes. I assume they have the plate in a mill with a rotating table to assure the slots are concentric to the center point. I had to slot mine perhaps 1/16".

[cajunwings]

Was very common for production planes to have a slotted front bulkhead. On the assembly line it could be rotated as needed to align and if you bought one as a replacement part you could just bolt it on.

Don Broussard
RV9 Rebuild in Progress
57 Pacer

[propjoe]

Originally Posted by cajunwings

Was very common for production planes to have a slotted front bulkhead. On the assembly line it could be rotated as needed to align and if you bought one as a replacement part you could just bolt it on.

Don Broussard
RV9 Rebuild in Progress
57 Pacer

Yup, The older Mooney and Arrow propellers have the slotted front support. I work in a prop shop and we always tag that front support when we send them back.
"Align, Tighten and Safety bolts".

[sf3543]

Just had this problem last week changing a prop on an RV6A where the holes where off by an inch or so.
Like Paul, all I did was:
-Install the spinner with both bulkheads on the prop and screw in the rear bulkhead screws
-Marked the front bulkhead holes through the existing spinner screw holes with a scribe
-Removed the spinner and front bulkhead
-Drilled out the nut-plates in the front bulkhead and reinstalled them after drilling through the marked locations