Rail Rider Again

[docbar]

Need some rail rider professional advice. After aligning a car perfectly, no noticeable turning, with only one shim behind the front right wheel and one shim behind the back right wheel. It was hard for me to take this car and intentionally make it turn, but I did. After about 8 feet it moves about 3 inches from the line, this only took one more shim behind the front right wheel. The rec. for the R.R. is about 1 inch per 2 feet (per warp speed). If I decide not to shim anymore will this be better than having it go straight or do you have to go with the 1 inch per 2 feet. I did cut off 1/16 inch off the front right side. We will get to practice the night before and the race will be on a wooden track which was smooth last year, didn’t notice any jumping around.

[WarpSpeedINC]

Since you have a test night on the track you will race on, I would leave it the way it is, run it a few times, then make any adjustments necessary to keep it on the rail. The reason I say run it a time or two, is the car may settle in a little, and initial alignment may change. Also it will change slightly with speed, as compared to a slow roll.
If the car is staying on the rail with the small adjustments you have made, you should be there!!
The reason I like the slight bend in the axle for front adjustment, is that it can be done quickly, and in small incriments. It makes it easier to hone in on the sweet spot. We start on the rail, adjust so it comes off a little, then readjust a touch. Check in all lanes if possible, just to make sure there isn't a level issue from lane to lane.
Good Luck and Keep us posted!

Warp Speed

[docbar]

Thanks warp.
Usually on practice night there is a lot of kids running around, running cars on the track, not the best time to make adjustments such as alignment. But I will play it by ear. I have two back ups, once I get them aligned and feel good about it I will another shim in the RR. It seems not to be turning as much tonight as it did last night.

[doct1010]

Doc,

If by RR you mean right rear, I don't think I would touch the rear. I think Warp would agree, get the rear as perfectly aligned as possible. Shim front loaded only. As per Warp, a little too much MAY be better than not enough. We learned this from experience. Our pack winner was tuned to turn 2" in 5' (Warp recos a more aggressive turn) after the event I checked it was closer to 1" in 5'. Still was very fast not as smooth. It did get a shot in the rear (3rd heat) that may have caused the change.

ps. I just reread (more carefully) your posts, RR=rail rider. DUH

[docbar]

doct1010, RR is rail rider, I believe I may have left out a word also. Been staying up late and not much of a typer forces me to take shortcuts.

[gtobob]

Since you have a test night on the track you will race on, I would leave it the way it is, run it a few times, then make any adjustments necessary to keep it on the rail. The reason I say run it a time or two, is the car may settle in a little, and initial alignment may change. Also it will change slightly with speed, as compared to a slow roll.
If the car is staying on the rail with the small adjustments you have made, you should be there!!

The reason I like the slight bend in the axle for front adjustment, is that it can be done quickly, and in small incriments. It makes it easier to hone in on the sweet spot.

We start on the rail, adjust so it comes off a little, then readjust a touch. Check in all lanes if possible, just to make sure there isn't a level issue from lane to lane.
Good Luck and Keep us posted!

Warp Speed

[gtobob]

Sorry about that last post...haven't got the hang of that quote thing.

Warpspeed, if bending the axles works well for the front axle, why not the rear ones too? I used a hardwood for a thin rail so deflecting the axle with shims didn't work. In fact I think I ending up bending it anyway...but it rolls straight now! So, what would be the problem with this bent axle in the back.

[WarpSpeedINC]

Sorry about that last post...haven't got the hang of that quote thing.

Warpspeed, if bending the axles works well for the front axle, why not the rear ones too? I used a hardwood for a thin rail so deflecting the axle with shims didn't work. In fact I think I ending up bending it anyway...but it rolls straight now! So, what would be the problem with this bent axle in the back.

We like to use shims in the rear, if any adjustment is needed. We try to build "perfect" rear alignment into the car, by using perfectly straight axles (Pro axle press a must!), straight axle slots that are cut 90 degrees to car centerline, and high precision wheels. If all of this is done properly, the car will require no alignment in the rear.
The reason I don't suggest using the bent axle method in the rear, is that you are adusting all plains at once by rotating the axle. It is pretty easy to get into left field trying to fix a slight toe in / toe out problem. Make sure the bend alway stays up, and if the car requires more than a thou or two of bend in the axles, you need to fix another problem. We have used this method before, but only suggest doing it in an emergency, and with a very small bend (couple thou at most) when doing so.
We like to use the bent axle method in the front, because it allows small changes without removing the axle. Also, you are generaly adjusting just the dominant wheel (three wheelers) so the chance of getting out in left field are cut in half.
If we have to adjust the rear, we will use shims, but will generaly build a new car also!

Warp Speed

[docbar]

Warp, you build a new car if you have to use any shims in the rear?
How many times on average do you have to strike the press to get straight axles?

[Pinewood Daddy]

How many times on average do you have to strike the press to get straight axles?

I use the mark, 3 hit, rotate 120 degrees & repeat twice method (per instructions). I then put them in my cordless drill and slowly rotate, and use a white thread on my jeans as a reference mark to determine run-out. Sometimes I'll roll them on a known flat surface (per Stan's method).

Most axles will be fairly straight (.002?) after 1-2 cycles, others I've had to rotate the mark 180 degrees and they're still not straight after 6-7 cycles!!

I've thought about using the Pro-Axle Press in an arbor press. If it works, it would save the tool. Mine is a little banged up.

[WarpSpeedINC]

Warp, you build a new car if you have to use any shims in the rear?
How many times on average do you have to strike the press to get straight axles?

It seems if we have to add shims in the rear, we have messed up in construction or axle/wheel prep. Not to say the car is junk, and can't be corrected with shims, but our fastest stuff requires nothing in the back.

How we straighten axles, is mark the head of the axle, and install in the axle press. we then give a couple a light hits, spinning the axle 90 degrees each time. We then gently hold axle press at parting line, and gently but rapidly tap with the hammer. With a little practice, you will get the axle to spin as you are tapping. With practice, run-out under .0005 is easily achievable.
We install them in a lathe collet to check for run-out. If using a drill press, or other non precision device, you will also be measuring chuck run-out, and get incorrect / inconsistant readings.
If using stock BSA axles, we LIGHLTY file the burrs before straightening.
The Pro Axle Press is a Great Tool!! and a MUST HAVE for prepping axles of any kind!!

Warp Speed

[SpinDoctor]

The Pro Axle Press is a Great Tool!! and a MUST HAVE for prepping axles of any kind!!

Warp Speed

Since this is the second time you said that in as many posts... I know what my next purchase will be.

[docbar]

I built four cars this year to allow for mistakes. One did not require any shims in the back while the other two needed no more than two. This was because they were favoring the car side a little and it would appear to me it would be better to have them favor the axle head ( one shim under each axle). One of the cars had 4 shims in front of one and two in the back of the other. It rolled straight forward but drifted when rolled backwards. According to the way it rolled taking out any of the shims would have made it worse. Something happened during the drilling process. I think it is better to give this one to the kids for a toy.
I do have a axle press and like it. Did not use it at the 90 but at 120, will try 90 next time. Wonder how effective a hydraulic press would be with the axle press?
May try to check alignment before doing anything to the car, just sit some weight on top.

[clemsontigerfanatic]

The Pro Axle Press is a Great Tool!! and a MUST HAVE for prepping axles of any kind!!

Warp Speed

Since this is the second time you said that in as many posts... I know what my next purchase will be.

3 cars 3 races Awana and Cubscout District April 1 along with Cubmobile race.
Used Pro Axel press and slight bend in the front dominant axel /.
Drifts 1"to 2" in 4' on the kithcen table so that the spinning wheel goes to the rail. The extreme graphite on the wheels.

Its always been aligning was the hard part. This year its the waiting.

After 1 cubmobile and 3 races it is going to be a long day,

Highlight should be the District race at the Chevrolet dealership with our brand new track,