What Size Wire Drive for 21

[Wasted wages]

yeah, but the end of the shaft and the hole in the stub shaft,,, are they broached like a hex key ? can't just be glued together right ?

 

[John Beardslee]

yeah, but the end of the shaft and the hole in the stub shaft,,, are they broached like a hex key ? can't just be glued together right ?

Nope, nothing elaborate, just a hole to fit the wire and an alignment fixture

 

[Jeff Lutz]

This seems to work best. Fit up and cleanliness is critical

660 loctite ‘quick metal ‘ is the best for attaching these together. Give it a try. I learned about it from making dies for a company that forms pellets that go into catalytic converters. Later a guy in the shop missed his interference fit on a bushing, so he turned it .005” smaller than the bore and used 660 on it. He installed the bushing halfway and got distracted. Came back and he could not beat it in with a sledge hammer. Just use it plain with no activators at all.

 

[Wasted wages]

That amazes me that the shaft is not keyed in any way and that the slip fit and glue holds up to a 90 or gas motor....

just don't get that warm fuzzy feeling that I get with a 1/4 flex shaft.. I guess if your going for speed records where every ounce of power matters, I can see it, but heat racing..? IDK...

 

[Jeff Lutz]

That amazes me that the shaft is not keyed in any way and that the slip fit and glue holds up to a 90 or gas motor....

just don't get that warm fuzzy feeling that I get with a 1/4 flex shaft.. I guess if your going for speed records where every ounce of power matters, I can see it, but heat racing..? IDK...

Well it does. The wire will break in most cases before it slips the hub. The binding strength of quick metal is hard for some to understand. But it’s for real.

 

[Charles Perdue]

I first must say that I have not tried the 660 Loctite to hold the wire into the stub shaft. I did not know about it at that time.

It was about 10 years ago when I began to play with the wire drives. I ended up using a thick walled 3/16 diameter stainless steel tubing for the stub shaft with the ID drilled slightly larger than the wire size. I tinned the wire and the inside of the stub shaft with stay-brite solder using a soldering gun, no torch or flame, to solder the two pieces together with the wire going completely thru the stub shaft. Just for insurance and using the same set screw that held the drive dog, secured the wire by drilling thru one side of the stub shaft into the wire and putting a spot on the wire itself.
Maybe over kill but I never had a problem with this setup.

Charles

 

[Wasted wages]

^^^^ Now that I have no problem with...^^^^

Risking loss of a high dollar prop to a metal glued joint, that I do...
I guess time will tell how good these wire drives are. For now I am going to stick to the tried and true... Don't need to see my name in the record books ..

 

[dr gary turner]

So, Doc, there must be enough wall in the strut to allow boring to the BB O.D. then, right?

Very close
Done with a mill. Drill then reamer

 

[Timbo Whalen]

Very close
Done with a mill. Drill then reamer

Thank you, Doc.