Care & Feeding of Knock-Off / On wheels

[Keith]

Knock on wheel spinners..Which Way?

There was an extensive discussion recently on the merits of different methods of mounting the tri eared spinners and I don't think a consensus was reached. However, Colin Chapman seemed to maintained the moral high ground despite some eloquent science disputing his method.

I just wanted to post this clip showing an Indy 500 pit-stop in 1950 and the poor sod who's job it was to change front tyres, (plus a bonus clip of a 2013 F1 pit-stop).

It is quite clear which direction is on and off at least in 1950. Does this add anything to the discussion? Anyone spot a procedural error?

http://biertijd.com/mediaplayer/?itemid=47217

 

[Jac Mac]

Resurrecting this thread for Keith who has apparently found some relevant info to add.......but couldn't find the relevant thread... perhaps it got knocked off in the right wrong way..

 

[Keith]

Thanks Jac...post moved.

 

[Ady]

A newbie owner but here's my view on spinner direction... I started by thinking about the motion of train wheels which is perrhaps better understood?

A train wheel uses a tapered cross section to self-centre itself between the rails & not bang side to side down the track... also to steer around corners, nothing to do with flanges (far too noisy). At the start of a bend a centrifugal force begins pushing the locomotive / carriage outwards. The outer wheel now riding up on a larger diameter, the inner wheel on a smaller diyameter. As the axle is fixed between opposing wheels the outer wheel travels farthest having a larger diameter on the rail & steers the axle into the bend. If over cornering or the track straightens out the inner wheel rides up on the larger diameter, the outer wheel rides down & so corrects the oversteer. Flanges are only there to prevent derailing whilst crossing points.

I have nuts / spinners with a male cone fixing a wheel with a female cone, Right hand thread on the right hand side, left hand thread on the left hand side, opposite to advice in many threads (& not a 'tight arse'). They have never stressed the safety wires, & believe the same thing is going on as with train wheels... self correcting using tapers.

If the nut is tight, nut & wheel mating faces have matching concentric diameters along the length of the taper & everything is good. But if the nut becomes slack the nut has unwound, moving outwards & away from the female taper in the wheel. The nut has effectively shrunk inside the wheel & the mass of the car is now supported only at the top of the nut. The nut has a smaller concentric cone diameter contacting the wheel cone diameter & an epicyclic gear is set in motion. The nut will spin faster than the wheel & winds itself back inside the wheel cone until the epicyclic motion ceases & full contact of the mating surfaces restored. The nut has self tightened in the direction of travel.

Therefore to self tighten a nut with a male cone...
Right hand side = right hand thread & left hand side = left hand thread

If the nut had a female cone & became loose, the opposite applies, the nut would support the car at the bottom, rotate slower than the wheel & would need a right hand side = left hand thread to self tighten.

 

[Neil]

I ruined the front wheel bearings on my 250GTE by using a knock-off hammer when the wheel was off the ground up on a jack. Don't do that.

 

[Bill Kearley]

Please check your info on nut rotation !!!!!!!!!!!! You turn the nut in the direction of wheel rotation to remove the them.

 

[Frank Catt]

F1 pit stop video a few years out of date, check the current total stopage time which I think has recently reached 1.80 seconds.

 

[Howard Jones]

Wow..……...This is a old thread. I mostly reread it and Jac Mac is still correct.

so to add my 2 cents.
Use anti seize, a little will do. don't make a mess!

Safety wire so that the wire must break for the spinner to loosen. That way you can simply look at the safety wire and see if things are going wrong. It won't keep the wheel on but it will tell you that it might be coming off.

I use a 2 foot long piece of aluminum rod 6061 about 2 1/2 inches in diameter as a driver. I place one end on the wing leg and hit the other with the hammer. You can use any 2-3 pound hammer because you are now only making contact with the spinner with the alum drive rod. Since you are holding the driver rod in the other hand you can feel the impact of the hammer very acutely. Let you senses tell you, you have it tight enough.

If you are a gorilla don't hit it too hard and if you are a fairy hit it much harder. Everybody else give it good go until you feel that it has stopped moving and the sound and feel of the driver tells you that's enough.

My GT40 has 30000 miles on it and about 1/2 of that is on track over nearly 20 years now I guess. Nothing has come off yet.

 

[Bill Kearley]

Ady, check the video on Olthoff Racing site.