Pitsco Wheel Lathe

[gpraceman]

I wonder if this would work or could be modified to work on PWD wheels.

http://www.pitsco.com/Technology/Dragsters/Wheel_Lathe

[Vitamin K]

Hmm, so what's not entirely clear to me is what the mechanism of turning the wheel is. Is it just friction-fit on an appropriately sized pin that rotates in order to spin the wheel?

This would have some serious problems for folks seeking a precision wheel. Not to mention, the pin is likely not sized to fit a PWD wheel.

[gpraceman]

It's hard to tell from their documentation, but it seems that the wheel is a friction fit to the shaft.

https://c10645061.ssl.cf2.rackcdn.com/r ... _39311.pdf

[Vitamin K]

It's hard to tell from their documentation, but it seems that the wheel is a friction fit to the shaft.

https://c10645061.ssl.cf2.rackcdn.com/r ... _39311.pdf

Yeah, that seems unhealthy for bores, IMO.

[gpraceman]

It would still be interesting to see if it can be modified for PWD wheels. I like the idea of a relatively inexpensive motorized wheel lathe.

[Vitamin K]

It would still be interesting to see if it can be modified for PWD wheels. I like the idea of a relatively inexpensive motorized wheel lathe.

I like the idea too, as I'm always eager to see affordable tools that can be used to produce quality components.

I think you'd need a different mechanism for turning the wheel if you were to make it practical for Derby use. Maybe some kind of rubber wheel that would press against a wheel on a free-spinning bore and would rotate to turn it.

I wonder if you could build a rig to add a motor to a Derbyworx shaver?

[ngyoung]

Biggest challenge I see is getting an arbor that replaces the stock one they use. Then installing it without any run-out. If I read it write, I believe that even the wheel vendors chuck a pin and calibrate it to like the 10,000th for run-out and press fit the wheel on it.

[Vitamin K]

Biggest challenge I see is getting an arbor that replaces the stock one they use. Then installing it without any run-out. If I read it write, I believe that even the wheel vendors chuck a pin and calibrate it to like the 10,000th for run-out and press fit the wheel on it.

They don't use the pin for the actual holding of the wheel though, do they? I thought a secondary clamp was typically employed after using the pin for locating the center. Not entirely sure about that, though.

[davet]

What about the roundness of the outer diameter of the inner hub? I've seen aftermarket BASX wheels where the outer diameter of the inner hub is very much out of round. With canted axles this causes a loud clicking as the high side hits the body. I wouldn't spend $129.00 only to true the outer diameter as that's only 1/2 the job.

[Speedster]

Mr. Fred Wade of Pitsco advised the wheel is held in place through the use of an arbor. I looked up the word "Arbor" and got "Mandrel". Definition of mandrel : a usually tapered or cylindrical axle, spindle, or arbor inserted into a hole in a piece of work to support it during machining. If everyone now understands how the wheel is held on that lathe, my Hat is Off to you.

[Stan Pope]

It means a friction fit between wheel bore and mandrel.

Depending on the taper, either the wheel may slip if the cutting rate is to fast or the mandrel may distort the bore.

The location of the wheel on the mandrel will vary depending on the diameter and taper of the bore. There is, therefore, no support for the wheel other than the bore. Separate clamping of the wheel by other (stronger) surfaces is not available.

Since the mandrel is less than 0.1", the cutting rate needs to be slow enough that the mandrel does not bend. Alternatively, a "steady rest" that directly supports the wheel or mandrel. Supporting behind the wheel is problemmatic since its location needs to change as the wheel radius is changed!

[Speedster]

Thank you. I now understand.