Wood type for wood prop?

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Aviacs

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Oct 21, 2019
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My Sterba has urethane edges.
Not sure it is Devcon, though. (not that it matters, either) :)
It is woodtone/amber or tan color.

I used to use Devcon urethane and the various primers, modifiers and accelerator to stick wood parts to steel and bronze components.
Also moulded it into feed rollers as custom aftermarket replacement, for solid steel planer feed rollers. For myself, and a few other people who liked the idea. Another cool thing you can do with the product is saturate fabric, and wind it over a mandrel (form) to make custom flexible ducting and hoses. The Devcon i used was essentially black. (the resin was clear, so on mixing, it made a sort of translucent black part.) It sure is tough. one set of feed rollers in my 20" planer has 3 decades of fairly hard use and still fine.

Most of my use was before the internet. But a few years ago i looked into getting another gallon, and shopped a bit online. Did not come to a resolution, but there are castable polyurethane products that cost about 1/2 what Devcon does. OTOH it's sort of like WEST epoxy - I am so confident and familiar using it over 40+ years that i won't try other products that cost a fraction, out of superstition. Devcon is also like WEST in the sense of a "system". There's the basic 2 parts resin/hardener. But you need durometer modifier to tailer the hardness desired. If you add that to the mix, then you need accelerator, since the modifier slows the set down too much. Then, depending on the substrate, there are primers to ensure a superior bond.

smt
 

speedracer

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Feb 4, 2020
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I have bought about 4 Culver props and the bolts holes and center hole were varnished inside.
When I get a new wood core, carbon overlay prop I treat all (7) holes with epoxy thinned with acetone.
 

Martti Mattila

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Feb 24, 2021
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Hello from Finland, I have made 40 wooden propellers, five in U.S.A. one is still hanging in EAA chapter 216 clubhouse wall. In U.S.A. I use outdoor carpenter clue, some in Finland too. But nowadays mostly epoxy, West System or Hempell marine clue. Dont never use a wood that has natural resin in it, it wonders out from tips because centrifugal force, expecialy in hot weather. I too wrap atleast outer half of blade with glass cloth and epoxy. To prevent splintering, under that wrap I put this epoxy leading edge. So wood from big leaf tree. Mostly Birch or Maple, try to get two laminations all the way to blade tip, to avoid distortion. In Finland some lost one only replica plane when beautiful Aussi prop separates its Urethane leading edge causing unbalance. I have E. Cluttons booklet. Made my first tree blade last summer to use in six cylinder McCulloch 650 two stroke.
 

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Jsample40

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Western North Carolina
In 1982 I commissioned "Woody" of Woody's Prop Shop on West coast of Florida to create a 50 X 27 two blade prop for "Golder Quest", my Mitchell Wing B-10 that took several awards that year at Osh Kosh. I provided the solid Walnut lumber, and he did a masterful job of cutting a beautiful prop with the Urethane leading edge others have mentioned here.. I flew with that same prop from 1982 to 1989 with several different engines, and it never showed a "ding" or damage of any kind, even though most of my flying was in grass strips (versus hard surfaces). That leading edge treatment is, in my humble opinion, the best approach to props I have ever experienced. Still have that beautiful prop today and plan on installing it on the KFM engine for my Mitchell Wing A-10 I'm restoring.
Jay Sample
 

Lendo

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Brisbane
Jay, I too am impressed with the Urethane leading edge, never heard on an edge separating, unless the timber gave away under the Urethane, which is VERY tough.
George
 

Doran Jaffas

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Jun 25, 2019
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An often overlooked place for the introduction of moisture are the holes in the prop hub. Raw wood is often exposed inside those holes with only a bolt or shaft to close them off. Has to be a better way...
I have built my own propellers in the past. Not exactly the fastest way but very satisfying. What I do but I do to waterproof the holes is simply put is what a thin coat of a verithane inside them. I'm sure this is not a new idea.
 

Doran Jaffas

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Jun 25, 2019
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My Jodel's prop was hard maple, built by Colin Walker of Surrey, BC. I don't know if he's around anymore. Maple has the right combination of hardness, split-resistance, weight and so on. The prop is the flywheel, so I wouldn't use a light wood like spruce. Too soft, anyway. Fir splits too easily. Considering the amount of time one will spend building hos own prop, I don't know why he would use a cheap wood. Or cheap glues. The urea-formaldhyde glues you find in the hardware store have wood dust as fillers in them, and some homebuilders have had poor luck with them. I can't find Aerolite glue listed anywhere anymore; that was the stuff used in certified wooden airplanes. I have used a bunch of it.

Colin Walker had a unique leading edge treatment: he milled off about 1/2" of the leading edge for some distance in from the tip, made a mold of some sort, maybe just tape, and filled it with a hard urethane from Devcon. Then shaped that to the blade's airfoil. A lot tidier than a brass sheath, and stuck on there real good.
See Ed Sterba Props.
 

claude.bouzerand

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Feb 2, 2020
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Location
Toulouse France
Hi, here, in France a good friend of mine has build thousands of prop.with beech wood. He was well known professional .He designed and carved wood prop. from model planes until vary eze and he made urethane/ epoxy leading edges, and no issue !.
 

Dana

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Could not find any links to Sterba propellers, is he still in business?
As far as I know. He was linked through Great Plains but their page for him seems to be down. You can try his email, but note he's not real fast to reply:

ed_sterba
at
excite
dotcom
 
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Douglasville, Georgia
Happy to help. The more options we have for quality props the better. When I ordered my prop, Ed's lead time was not as long as Culver or Performance Props. His pricing is very good. My prop cost less than expected.
 

Doran Jaffas

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Jun 25, 2019
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Happy to help. The more options we have for quality props the better. When I ordered my prop, Ed's lead time was not as long as Culver or Performance Props. His pricing is very good. My prop cost less than expected.
I recently spoke with Aviator in the United Kingdom. He told me about Hercules Propellers. The performancy he is getting is pretty astounding. I've contacted them via email. I will keep you posted as to what I find out.
 

Doran Jaffas

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Jun 25, 2019
Messages
612
Happy to help. The more options we have for quality props the better. When I ordered my prop, Ed's lead time was not as long as Culver or Performance Props. His pricing is very good. My prop cost less than expected.
I have a sterba prop That is a little aggressive for my 0-200. I think it would be great for something in a 125 horsepower range. I have one hour on it. Put my Prince P tip back on. It is a beautiful propeller that I had made but but I lost some climb in the deal. Nothing against Ed Sterba at all. Excellent excellent price and very nice looking propeller.
 
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