Wheel Alignment

[ScoutDerbyDad]

Hi All,

I have a question regarding a pinewood derby car my son and I built.

We are allowed to run 1 raised wheel and canter the other. Ive got them gapped at .03in from the body. We drilled the rear axle holes at 2.5deg using the Pro driller tool and have the front right axle bent at 1.5deg.

The issue we are facing is the rear wheels migrate into the frame instead of out to the nail head. As the nails are straight, the only reason i can see for this is that the holes are not. What is the best way to fix this issue?

 

[Thinkin'Bout Racin]

I am not a pro, but will offer a couple of thoughts. Are you SURE that the rear axles are straight???? I would try rotating them a little at a time and see if the wheels migrate differently.

You can always glue a toothpick in the rear holes and redrill if needed. Are you SURE that your drill jig has straight holes? Does the body fit tight in the jig? Are you clamping the body into the jig before drilling? Does you drill bit fit snug into the drill jig holes/ bushings ......I could go on and on, but you can start to get an idea of all the things that can affect how the drill turns out.

 

[Pinewood Outlaw]

Maybe you put your body in upside down and drilled your rear 2.5 deg the wrong way. If they look like the image on the right then that probably it.

 

[DerbyDad4Hire]

Your gaps should be at least half that. The rears should be drilled at 3 degrees. The tool you used isnt ideal. Bend the front around 5 or 6 degrees.

As far as the wheel migration it is possibly the wheels. Stay away from bent rear axles.

 

[Reecedad]

Could your drill be bad? If that’s a possibility then either redrill or bend your rear axles.

 

[Pinewood Outlaw]

Could your drill be bad? If that’s a possibility then either redrill or bend your rear axles.

Redrill.....never bend rear axles

 

[Reecedad]

Redrill.....never bend rear axles

Although I’ve never bent my rear axles I thought it would be an alternative to redrilling for a Scout car. After all, DWS claims to bend his rear axles and you can’t argue with his success.

 

[Pinewood Outlaw]

Does he bend them or simply turn them to make adjustments?

 

[Reecedad]

Does he bend them or simply turn them to make adjustments?

He claims to bend them so he can then twist to tune.

 

[DerbyBoyz]

Does he bend them or simply turn them to make adjustments?

I would not bend your rear axles if it was me. I think it’s more of a very fine adjustment that you can get out of stock axles. If you do try to bend the rear axles on this car, I would do it at the slightest bend you could possibly do.

 

[ScoutDerbyDad]

Your gaps should be at least half that. The rears should be drilled at 3 degrees. The tool you used isnt ideal. Bend the front around 5 or 6 degrees.

As far as the wheel migration it is possibly the wheels. Stay away from bent rear axles.

The gaps are about the thickness of a credit card. The rear axles are drilled at 2.5°.
Ive never heard of a 5° bend on the front, is there a reason for it to be that high?

I was able to put a light bend on a spare axle i polished up and tune to the point where the wheels now migrate outwards when rolling forwards and backwards. This will be a rail rider and the car drifts about 1in over 4ft.

 

[TRE]

Too much gap

 

[ScoutDerbyDad]

Too much gap

How much do you suggest? (business card, folded piece of paper)

 

[TRE]

As tight as you can get without rubbing...i do it by eyeball

 

[Racing358t]

This will be a rail rider and the car drifts about 1in over 4ft.

That almost certainly won't be enough drift. 4" in 4ft is usually a safe place on properly aligned cars but sometimes they can want more or a little less.

Scott

 

[DerbyDad4Hire]

Yep not enough steer.