Wheel Runout

[B_Regal Racing]

I do not have any idea how wheel run out affects the speed of a given car; nor do I have any inclination to begin turning my own wheels. I buy 100% of my wheels from John (placed some obscene orders for them). I do not use the wheels out of the box, and usually discard them (or use them for the NDFW). That being said, is there any reason why I would need a wheel run out measuring tool? I know it could be quite handy for those making their own wheels (as well as for those using stock wheels), but I do nothing more than open the plastic bag from John, inspect the hub/bore, polish and wax, slap ‘em on a car, and let ‘er rip.

Given that context, I do not believe I would have a use for a wheel run out measuring tool, but it did look like a fun instrument to play with.

Discuss.

 

[pony express]

I've often wondered how to measure the wheel wobble on the car. I'm sure it would correlate with the speed. Some sort of indicator with the wheel on the car or in an axle in a vise possibly. The wheel does not have to be turning at the high rpms they experience on the track. It would give you an estimate of the wobble of a wheel's tread and bore mated to an axle.

 

[DerbyDad4Hire]

It can be checked spending less money. If you are making your own wheels then you would need a way to check. I true my mandrel to the the hundreth of a millimeter. The wheels fit tight so the trueness is dead on.

 

[GravityX]

0.010 mm equals .0004 of an inch.

B Regal Racing, if you are chucking those wheels, bag them up for me and send them my way. I need some wheels to practice my machining skills.

 

[Knotty Racing]

B_Regal Racing,

John has provided me with excellent wheels. I still like to know what I am getting and running, just like I count my money at the bank for deposits or withdraws.

That said I am in manufacturing and no matter what process is used to manufacture or modify something, there is variation in the process.

The number of .0004" is about 1/8th the thickness of a human hair. Doesn't take much to throw that off.

The quality of stock wheels vary tremendously and good and bad mold numbers change all the time. I've seen it in our 4 years of scout racing. I've seen stock wheel runouts from .0005" to .012" that's a big variance.

Can you check it cheaper? Absolutely, you can use a block of wood to make a similar unit. You can clamp a drill bit in a vice and use a mag base indicator holder on the vise to check it. Done the earlier, was not satisfied and the later doesn't provide for good enough hygiene around my bench vice in the garage with metal shavings everywhere.

I can bend an axle with a screw driver and a hammer, but a good tool for the job sure makes the task a lot easier. Just like drilling axle holes, you can use a drill bit and a fence to get your angle, but the silver bullet or a goat boy drill fixture, sure does make it easier.

Nice tools are not for everyone.