Poor Quality Wheels from Latest BSA Lot

General discussions for car and semi-truck racers.
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murphken
Master Pine Head
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Joined: Fri Sep 04, 2009 4:26 pm
Location: Harrisburg, PA

Re: Poor Quality Wheels from Latest BSA Lot

Post by murphken »

Same molds > They just change over to colors. I try to keep the wheel diameter as large as possible. Just enough for no radial runout and have all four wheels with the same diameter. In a good lot of wheels, most of the wheels clean-up around 1.1750" to 1.1820" except for the problem child mold numbers.
I only worry about wheel weight for lightened wheels. Usually my wheels are just under stock weight, 2.4g, 2.1g and 1.9 gram. Most racers buy the stock weight or just under wheels.
Lightened wheels are time consuming if not using CNC. In the past, some cutters, using CNC, were reaming the wheel bores. I assume that some cutters might be using multiple lathes with different mandrels and no bore reaming, just like me.
For lightened wheels, I usually do a bunch of wheels at a time and perform a defined cut on all the wheels and then, move onto a different cut. Cuts refer to: tread, inside edge, outside hub, inside hub and inside of wheel, opposite the outer thread. There is not much use to remove material around the wheel bore because it does little to effect the coefficient of inertia.
In the off season, I will post some information on how to set-up Seig Lathe to cut PWD wheels. I have an old Atlas and multiple highly modified Seigs. A Seig 7 X 14" is just the right size for cutting wheels. However, the Seig needs to be highly modified to attain beautiful looking wheels with precision dimensions. Otherwise, the wheels look like [junk] and it will be hard to perform some of the cuts with precision. It took me about five years to figure out how to do this.
SHINING LIGHT Pinewood Derby & Audio
Eagle
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Re: Poor Quality Wheels from Latest BSA Lot

Post by Eagle »

Murph,
You've been at this awhile. I know we've been discussing lot 0618.

If you had the ability to get wheels from any lot which one(s) would you look for to machine? Which are the best out of the box/sleeve?

Which mold numbers are best from that lot/lots?
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murphken
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Posts: 182
Joined: Fri Sep 04, 2009 4:26 pm
Location: Harrisburg, PA

Re: Poor Quality Wheels from Latest BSA Lot

Post by murphken »

Sorry for the late reply. I got a nasty case of covid and it took me about a month to come back. My thought is hat Lot #0618 was used for two production runs of wheels but I could be wrong. The latter ones were just pathetic. I am just past 500 sold sets for this year. I was fortunate to purchase the old stock and got me through the season. I would go with #8 wheels for the best chance of getting four good ones.
SHINING LIGHT Pinewood Derby & Audio
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