Rail Riding drifting wrong direction

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Yoderby
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Rail Riding drifting wrong direction

Post by Yoderby » Thu Feb 04, 2016 10:23 pm

I have a raised right wheel. When I roll it down a table it's drifting AWAY from the raised wheel rather than towards the raised wheel. I didn't bend any axles and I drilled axle holes. How can I adjust the axles so that it drifts the opposite way or at least straight?



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Re: Rail Riding drifting wrong direction

Post by Gtdhw » Thu Feb 04, 2016 10:57 pm

Did you see how it "rolled" down the table with the rear wheels on only? If it went straight with rear wheels only, then the front axle is where the adjustment is needed. If you did't test the rears only, then you might have the two rear wheels fighting each other, and one them actually steering the car, instead of the DFW. If you have the car completely assembled, and what you have, is just what you have at this point, I would first try & rotate the DFW axle a very minute bit at a time, to try & find a slight bend, that would work to your advantage. If that was a no go (nice super straight axle), I would try some good finger pressure to try & toe in the DFW to the point of at least rolling straight. Then me being me, I'd probably keep trying to push it enough to get it steer right. If that didn't work, I'd be pulling the axle and finding a crude way to get a sight bend in the dang thing, lol.


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Re: Rail Riding drifting wrong direction

Post by Yoderby » Thu Feb 04, 2016 11:02 pm

Thanks for the ideas, I can't believe I messed up so badly. I tried, but not hard enough.



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Re: Rail Riding drifting wrong direction

Post by Gtdhw » Thu Feb 04, 2016 11:13 pm

Don't be so hard on yourself. After finding this fantastic place just recently, I've learned that all 8 cars that we've built over the last 4 years, were all wrong, in may ways, lol. This place is really is packed with tons of excellent information. We can hardly wait until our races this year, to see if everything that we've learned, we were able to put to use correctly, or.....if we got closer, but still messed up. IMO, that's 1/2 the fun.


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Re: Rail Riding drifting wrong direction

Post by Scrollsawer » Fri Feb 05, 2016 6:07 am

I think we ended up building one of those once, also quite by accident. As I recall, that car ran really well with the raised wheel doing the rail riding (I think it won a speed trophy). I do not recommend that approach (fix it if you can), but if you cannot not, it's a lesson learned, and If other build principles are still there, then those will make the car go faster than most.

How high is the raised wheel? Is it tilted away from the car, or is it still in a normal wheel position (I.e., is the wheel tread still parallel with the track?).

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Re: Rail Riding drifting wrong direction

Post by Speedster » Fri Feb 05, 2016 6:18 am

Is your test surface really, really, really level? Did you narrow the car 1/16" behind the DFW"? You stated you didn't bend any axles. You must bend the axle steering the DFW. Switch the Front axles and wheels and see what happens.



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Re: Rail Riding drifting wrong direction

Post by Yoderby » Fri Feb 05, 2016 9:59 am

I used Pinewood Pro PRO Axle Driller to drill the axle holes with a clamp. I didn't narrow the car 1/16" anywhere nor did I bend any axles. However I think the axles may not be perfectly straight due to my polishing or something. I had to hammer the nails in to the hole such that I don't know if I can pull them out easily. I did try rotating the DFW axle just in case but that didn't help. The raised wheel is about 1/4" high and is not tilted at all. Weigh-in is coming soon so I need to act fast. I think I'll try to bend the axle by pushing down on the wheel while the axle is still in the hole, maybe that will alter it just-enough. Thanks.



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Re: Rail Riding drifting wrong direction

Post by Scrollsawer » Fri Feb 05, 2016 10:49 am

Yoderby wrote:I used Pinewood Pro PRO Axle Driller to drill the axle holes with a clamp. I didn't narrow the car 1/16" anywhere nor did I bend any axles. However I think the axles may not be perfectly straight due to my polishing or something. I had to hammer the nails in to the hole such that I don't know if I can pull them out easily. I did try rotating the DFW axle just in case but that didn't help. The raised wheel is about 1/4" high and is not tilted at all. Weigh-in is coming soon so I need to act fast. I think I'll try to bend the axle by pushing down on the wheel while the axle is still in the hole, maybe that will alter it just-enough. Thanks.
Is your weigh-in today?

If I were you, I would try to gently rotate the axle in question a tiny bit by carefully using needle nose pliers. That may be enough to steer the car correctly. If not, the second option would be to try and take the axle out of the hole, using needle nose pliers (provided they are not glued in), then adjusting the axle, then re-installing the axle and wheel onto the car.

Pushing down on the wheel with enough force to physically alter the axle can't be good for the wheel bore. Above all else, remain calm throughout the process. Being in a hurry is never good, so try and slow down. :2cents:

Just my suggestions.

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Re: Rail Riding drifting wrong direction

Post by Yoderby » Fri Feb 05, 2016 10:57 am

Yes, weigh-in is today. I tried rotating front axle with no change. I'll try again to make sure. If I do need to remove front axle I'm not sure how to adjust it but I'll do a search again. Thanks.



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Re: Rail Riding drifting wrong direction

Post by gpraceman » Fri Feb 05, 2016 11:32 am

One thing that has worked for me is Stan Pope's old wax paper shim technique. Pull the FDW, place a sliver of wax paper on the rearward side of the hole, carefully insert the axle, trim the excess paper sticking out of the hole with an xacto knife, and then do a test roll. If that doesn't fully correct the problem, then try a double thickness of paper. Some may frown upon that technique, but to me, if it works, then I don't care if someone else thumbs their nose at it.


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Re: Rail Riding drifting wrong direction

Post by Yoderby » Fri Feb 05, 2016 2:22 pm

Well, it turned out I was wrong when I said I rotated the front axle. I thought I did, but today I marked the axle top with a sharpie and realized I never actually rotated it. Once I applied way more strength I rotated it a quarter turn. No good. Then I rotated it another quarter turn so the mark faced down. Now when I roll it across a 6' table it drifts a few inches TOWARDS the raised wheel. However, I never narrowed the front side 1/16", will I still be ok with the rail riding? Thanks everyone for the help I feel much better now.



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Re: Rail Riding drifting wrong direction

Post by Speedster » Fri Feb 05, 2016 2:48 pm

It will probably ride the rail but the following rear wheel might also ride the rail.



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Re: Rail Riding drifting wrong direction

Post by Yoderby » Fri Feb 05, 2016 2:53 pm

Would that make it worse than if had run straight? If so maybe I should tweak it to see if I can get it to run straight



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Re: Rail Riding drifting wrong direction

Post by john4840 » Fri Feb 05, 2016 8:27 pm

Make a test board with a wooden yard stick as the center rail. Raise one end of the test board about 3 or 4 inches and make sure it is level. Run your car down the test board. Make sure the car rolls slow enough that you can observe the rear wheels.

John



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Re: Rail Riding drifting wrong direction

Post by Yoderby » Sat Feb 06, 2016 12:14 am

Well, I'll have to do it next year as I handed in the car. It's out of my control from now on but I'm glad I was able to get to roll straighter thanks to help on here.



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