Props and Prop Extensions

The RV3 less engine I just purchased came with a late eighties vintage Spool
type prop extension that fits my 0235 C-1 prop flange. Are there any issues
I should be aware using this extension with the long prop bolts? Does Van's
sell the long prop bolts? As for props has any one company been recognized
as the best supplier of RV3 Wooden props? I have heard of some using composite props and would like to hear opinions on those and which ones
have been used.

Thanks
Jim Miller

extension

When you say spool type, this type uses two sets of bolts. Later you say long bolts. The two statements are contradictory. The short extensions normally use one set of long bolts. The spool type, usually three inches or longer use two sets. The Saber mfg people in TX can fix you up with most anything including crush plates and bolts.

It looks like a spool you see that holds heavy wire. It could easily have
short bolts bolting one end to crank flange. The prop end has no threads
in the "spool" bushings and would require bolts and nuts. Is this the way
they are used with bolts and nuts on the prop side? Also one other important
question. My engine crank flange has one bushing that has a larger diameter
that extends about 1/4" forward of the crank flange face for prop indexing.
The prop extension has all six the same with no accomodation for the one
with the sholder. It would require either modifying the extension by enlarging the first 1/4 of one hole or machining the sholder on the one
bushing until it is flush with the crank flange face.

Thanks
Jim Miller

I can not speak for the suitability of the extension, but Saber sells prop bolts.
I recently had my Bucker prop refinished and part of the prop shops service was a complete test and inspection of the bolts and extension. A prop shop might be able to help you.

For around $500 or less, you can take all of the risks of using an unkown extension and get something designed for the job from Saber

Saber

We have an 8" extension on our Cozy Mk-IV. It is from Saber. The machining on it is beautiful. I've been machining things off and on for the past 20 years or so, and their work is gorgeous. They can supply you with the proper bolts, crush plates, etc as well.

http://www.sabermfg.com/

I send all of my customers to Saber Mfg. Sam is a great person to work with, and as said earlier buy a new extension and bolt set and remove any risk in those parts.

I have talked with Sabre and they have answered all my questions. Part
of my problem is I forgot that the ring gear and pulley had to go on which
explains the one bushing being oversized. My extension is an older one
with potential problems and I will replace with a new one from sabre.

Does anyone have experience with composite props. Mainly interested in
the one piece without any metal hub.

Thanks
Jim Miller

jim miller said:

Does anyone have experience with composite props. Mainly interested in
the one piece without any metal hub.

Thanks
Jim Miller

Click to expand...

"composite" covers a lot. For instance, my Hoffman prop on the Bucker is considered a composite as it is made of wood with a fiberglas covering and metal leading edge, but it is basically a wood prop.
There are a lot of choices to consider with your prop selection so I would not rule out any type of construction until you weigh all your options.

Props and extensions

JonJay said:

I would not rule out any type of construction until you weigh all your options.

Click to expand...

That is a wise comment- from a w&b perspective as well. Have you worked up a projected W&B? If you haven't, now is a good time, as what you buy and hang on the front has the most value for correcting rear cg. I don't know what you will be doing for electrics, but if you plan to go without, that will make your prop choice all the more important, maybe look at metal- if one is made.

best
Stan