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Old 01-02-2012, 10:49 AM
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fredsedno
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Default wheels

Happy New Year!
My question concerns radial and/or axial runout on wheels: I have 3/12"wheels that runout very noticeably. Are they ok?
These wheels ran out right from the box & were made by a very well known company. I can picture these wheels moving at 3o/40 mph, the revs. are high and vibration must be significant.
Any input will be appreciated, fredsedno
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Old 01-02-2012, 02:12 PM
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Default RE: wheels

I would think the biggest issue will be tire wear.
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Old 01-02-2012, 06:10 PM
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Default RE: wheels

There is no reason for that, unless the rubber is wrongly installed over the rim.

Both parts come form molds that are machined perfectly concentric.

Check for manufacturing defects and return them as needed.

Happy 2012
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Old 01-02-2012, 07:52 PM
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Default RE: wheels

Ok - I need to learn something today to meet my quota ...

What is "run out"?
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Old 01-02-2012, 09:40 PM
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saramos
 
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Default RE: wheels

It's the term used to discribe how off axis the rotation is. If the wheel was not drilled perpendicular to the rotation, it will wobble. I don't know the term that is used for a situation where the hole is drilled perpendicular to the rotation, but offset (out of axis). This would produce more of an up-down motion.

I was introduced to the term when I got a Bosch router for my CNC machine. The first Bosch I got, the runout was so great that you could see the router bit wobble with the naked eye. I returned it for a new one which had a runout that, while not visible to the naked eye, was great enough that it would probably break my most delicate bits. It took a third party replacement part before I got the runout to under 2 thousandths measured at the end of my test bit. The smallest bit I have is .015" in diameter. I've not used it yet.
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Old 01-02-2012, 09:47 PM
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SeamusG
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Default RE: wheels

Thank you - excellent explanation.

Guess you could (re)drill the hole perpendicular to the wheel and either insert a larger axle or bush the wheel with a tube - brass maybe?
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Old 01-03-2012, 01:50 PM
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Default RE: wheels

Seamus, drilling and bushing the hub is only an option if the hole was drilled or molded off center in the first place. More likely the tire was not installed correctly and it's sitting askew on the hub.

Fredsaidno, if it's glued on like many foam tires are then you can either live with the runout or chuck the tire in a hand drill and use some very coarse sandpaper or a power sander with the tire running against it to reshape it and true things up. A light touch goes a long way if you do this. Also sticking the wheels in the deep freeze overnight will stiffen up the foam and let it cut better while still cold. Work fast as it'll warm up and get soft again pretty quickly.
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