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Discussion Starter · #1 ·
I like the thought of a pin.
Anyone see a reason this wouldn't work?
Thanks
Jack



[ July 15, 2004, 05:16 PM: Message edited by: stremboli ]
 

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We don't need no stinkin stitches
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Discussion Starter · #3 ·
Yes Larry, but it includes an inner backing plug, bolted to outer cap, that will not allow outer cap to pull out.
 

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I have no idea what is meant by "pin drive" but, the safety pin in the detail seems to serve no purpose. Everything seems to be able to slide back out even with the safety pin in place. I am sure that I am just missing something.
 

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slaga:
The car's wheel is located on the spindle (bright green) and held in place by a 'knock off' or 'spinner' (red ears). The red pin would serve to hold this spinner in place. There's been recent debate as to whether using safety wire for this purpose is safe/adequate. Pin drive refers to pins (not shown - Edit - now shown in blue) on the mounting surface of the adapter hub that locate into recesses in the mounting surface of the wheel.

I'm sure this would work well, a similar locking pin is a RACMSA requirement for racing cars with centre lock wheels.

[ July 16, 2004, 04:04 AM: Message edited by: UKCoupe ]
 

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Discussion Starter · #8 ·
Thanks UK,
The main idea behind this is to eliminate the possibility of the spinner coming off the hub.
Even if the spinner loosened to the point of contacting the clip, it would not come off, thus preventing the wheel/tire from parting ways with the car.
The outer cap which the pin goes thru, must be anchored to the hub, as shown with 1/2" SCHS and inner plug. There is probably a better/more elegant way to do this, but my thought is that this would be pretty bullet proof.
Thanks for the replies.
Jack
 

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Discussion Starter · #9 ·
Thanks Larry and others who responded.
I may whip up a proto to test the concept.
Jack
 

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Jack,

That would be cool, but the pin would have to be pretty much up against the spinner when the spinner is in the tight position. If not, the spinner can still thread out some and the wheel is allowed to wobble a bit (while the pin is still in) that wheel will eat up the pin or still cause a ton of damage. It's a pain because of some difference in people's backspacing and wheel sizes because there's different amounts of hub thread leftover from wheel to wheel. Kinda like safety wire: people think it's there to keep the spinner on, but it isn't and it won't...it's job is to serve as a visual cue that the spinner is beginning to turn...the safety wire has broke before (ask me how I know) and will not hold. You would be amazed what destruction a slightly loose wheel is capable of.

I say give it a shot at the prototype. Would be an attractive mod.
 

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Discussion Starter · #11 ·
Blue Corona,
I think that the whole assembly would rotate at the same speed.
Somehow the spinner would have to be rotataing at a faster speed to chew anything up. Since the pins would still be engaged and the wheel would still be on the hub, it may chew up the inner ID of the wheel but it could not come off.
My idea is only to prevent the wheel from ever rolling on past you as you grind to a halt. I would use safety wire as well as an indicator of loosening.
I would just feel better with a redundacy feature, just in case the wire failed. Since the spinner would still be engaged on the threads of the hub, the forces required to shear the pin would have exceded those of the hub/spinner threads
Thanks for the comments, I am still thinking this over as they come in.
Cheers
Jack
 

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Could you drill and tap the side of the spinner and use a set screw?
 

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Perhaps you could machine a slight lip on the outer diameter of the aluminum piece which holds the pin, flush with the spinner. That would create a clamping force on the spinner when the SHCS is tightened down. Probably a little more aesthetically pleasing than a big ol pin sticking out. Just a thought.

But wait, someone want to explain how you could install this? Is there easy access to the backside of the hub when the wheel and everything is intact? Would you have enough room to tighten down the SHCS?
 

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Discussion Starter · #17 ·
Brad,
You could reverse the bolt and somehow lock the inner plug.
Very good idea.
Thanks
 

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I think there is a little discrepancy in the earlier explanation of the adaptor.

The green part is the "knock off adaptor".

The blue parts are the "pins".

The red part is the knock off nut.

The pin drive wheel is held on the hub with the knock off nut.

Note that the knock off nuts are right and left thread for the different sides of the car.

While the wheel is turning in the forward direction the nut tends to tighten itself, from the action of momentum. During braking the momentum works to loosen the knock offs.

That is why some sort of locking device is necessary, you only get one chance to keep the nut in place.

The pin drive adaptor fits on the stock hub to convert bolt on wheels to pin drive wheels.

The blue parts are the drive pins. They attach the adaptor to the hub by threading on the existing lug bolts. The pins are smooth on the outside and fit into a hole in the back side of the pin drive wheel.

They act similar to lug nuts on an ordinary wheel in that they transfer the torque from the axel to the wheel. The holes in the back of the wheel are similar to lug holes except they don't go through the wheel.

The proposed locking device, that this thread is talking about, will only go through the adaptor so there is no problem with interference with the front hubs or rear axels.

The bolt goes through from the back. The outside adaptor fits against the hub of the pin drive adaptor, not the knock off nut. If the knock off nut does come loose it can't fall off the adaptor due to this locking pin. It can come loose enough to give the wheel a very squirly feel, but you can get off the road with the wheel still being a part of the car.

(Note that the flange of the outside adaptor could be made larger to act as a knock off nut stop that would contact the knock off nut sooner that the pin. Unless the outer flange is threaded and matched to the thread of the adaptor, the outer flange and pin have to be removed to take the knock off nut off anyway.)

Also I would make the 1/2 -20 bolt long enough that the locking pin would go through the end of the bolt as well as the outside adaptor flange.

If the adaptor and pin do rotate in the knock off hub, nothing will happen that would affect the knock off nut.

Finally, consider that the five lug nuts on a standard wheel are tightened to around 100 lb-ft. The knock off nut has to do the same job as these five lug nuts to keep the wheel firmly pressed against the hub and prevent the wheel from flopping back and fourth in the holes in the back of the pin drive wheels.

[ July 16, 2004, 01:33 AM: Message edited by: CRZN427 ]
 

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Stremboli,

Would a snap ring in a grove be as effective as the pin through a hole?? I was just thinking it may be more esthetically clean.

Great idea you've got going here.
 

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I'm an Aerospace Design Engineer by profession and I can't figure out a polite way to say that that's a poor design. Sorry for the bluntness, but there it is.
I'm assuming the spinner is threaded onto the 'green' revolved shape. If the spinner comes loose, you're facing a combined shear/thrust load. A cotter pin will not resist these load cases.
A much better design would be to have a wave spring against the outer face of the spinner, a machined cap (washer) behind the wave spring, and a large retainer ring that engeages the 'green' part that puts the wave spring/cap assembly under a slight preload.
Good luck-
 
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