Setup opinions

[Rat Pack Racing]

I am getting the grandsons car ready. The rules don't allow cant and must use stock wheel base (4.375"). We can run 3 wheeler though. I have the axle about .680" from rear (glued cut off piece to front), milled pockets. Track is wood with center rail. Body about 7/16 thick.
I have 2 rows of twelve tungsten cubes behind of and in front of the rear axle. This gives me a weight of .68 oz. on the right front wheel. There is 2.150 oz. on each rear. According to the COM calculator this gives me a COM of .597". This check out almost exactly on the balance test. Car weighs right at 5 oz. without paint (+/- .1oz.)
Anyone have any thoughts on setup for a car like this?

 

[Chief]

Sounds like you are doing well so far. I would try to insert the front wheel somewhat crooked so I could adjust the steer. If you can get it to steer 4 inches in 4 feet and as long as you polish the wheels and axles you should have no problems bringing home some hardware. What lubrication are you allowed to use?

 

[OPARENNEN]

IMHO, I would still cant the rears at 1 degree (maybe even 2 degrees???). Cants of that amount will not show when the car is placed flat, because of the bit of slack between the axles and the wheel bore, which is usually 5 or 6 1000ths (more or less).
If your rules allow for a bent axle to adjust the steer, go with that.
If bent axles are not allowed, get a predrilled block from DD4H so the DFW is already drilled at an angle, and the NDW drilled with a raise, thus no bent nails are required.

 

[Guest]

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[davet]

I am getting the grandsons car ready. The rules don't allow cant and must use stock wheel base (4.375"). We can run 3 wheeler though. I have the axle about .680" from rear (glued cut off piece to front), milled pockets. Track is wood with center rail. Body about 7/16 thick. I have 2 rows of twelve tungsten cubes behind of and in front of the rear axle. This gives me a weight of .68 oz. on the right front wheel. There is 2.150 oz. on each rear. According to the COM calculator this gives me a COM of .597". This check out almost exactly on the balance test. Car weighs right at 5 oz. without paint (+/- .1oz.) Anyone have any thoughts on setup for a car like this?

I'm curious as to how you can fit 24 cubes in a body that's 7/16" thick. Maybe I'm not reading it right.

 

[Rat Pack Racing]

We are allowed to use graphite only. There are 2 rows of 12, 1/4" tungsten Blocks in front of and behind the axle in 1/4" deep milled pockets. That leaves 3/16" of material above the pocket.
I forgot to mention I have a set of John's BASX wheels and 92X Pro axles with his prep.

 

[davet]

We are allowed to use graphite only. There are 2 rows of 12, 1/4" tungsten Blocks in front of and behind the axle in 1/4" deep milled pockets. That leaves 3/16" of material above the pocket. I forgot to mention I have a set of John's BASX wheels and 92X Pro axles with his prep.

Got it.

 

[GravityX]

1-2 degrees of cant, anyone could mis-drill a rear axle hole by that much, without proper tooling. I'm just saying. /images/boards/smilies/biggrin.gif