Rail Rider Problem

[trappist]

My son and I have been using the Rail Rider Tool from Derby Worx for 4 years now and I've never been that comfortable with the way I'm using it. I've read stuff here about how and watched the videos put out by Derby Worx.

I keep feeling like I'm bending the axle more than the 1.5 or 2.5 degrees the tool states. I see marks on the axles afterwards and sometimes a wobble develops in the wheel that wasn't there before we bent them. The bend just seems to be more than it should be, but I have no method of measuring it.

I've made sure we aren't over polishing the axles, having made that mistake before. We are choosing good wheel molds and prepping them as much as our rules allow (no shaving). Mostly just polishing the inside wheel bore and burnishing graphite onto the cone, etc.

Sometimes when adjusting so that the wheels move to the outside of the axle head, I can only get them to do that when rolling forward, but not backward. Spent hours trying to get it both ways, but forward was all I could get, so I went with it.

Is it possible with the way I'm striking the press with my hammer? I'm holding the axle against the RR tool with my finger while pinching the other side of the tool. Should I be striking dead center of the tool? Of course measuring just how much force to use is pretty subjective. The difference between a light, medium and hard strike for one guy is different for another.

My main concerns are:

• Should the bend in the axle after using the RR tool be really that noticeable?
  
• Should I expect to see some indentations on the axle shaft?(where it bent, not the spot where the wheel rides)
  
• Should I be that concerned with the wheels not moving out to the axle heads when rolling backwards when they do rolling forwards?
  
• What causes the wheel chatter to crop up after bending the nails and how do I prevent it?
  

Another thing is I inadvertently made it so we have a COM about 1/2in in front of the rear axle. Think I'll have a problem? We can't have an extended wheelbase, but we can move it to wherever we want, so long as the original distance between front and back are maintained.

[obsessedderbydad]

I don't know about the rail riding technique. I tried it this year too. Back wheels were aligned so when you roll forward and backwards they stay out. Front wheel turned so the car rolls to the rail so the downed front wheel touches the rail. Well at the race this happened, but it looked like the back of the car was at an angle when it went down the track. What's even scarier, the guys car that won and had the track record did not use this technique and you could see it go from side to side all the way down the track. He had the fastest time and beat everyone! So saying this is the best technique is debatable to me.

[chromegsx]

You will lose speed every time your car slams off the guide rails. Rail rider done right will win races. I've seen and done it against a known "experienced" builder locally. We tried Rail rider fo the first time last year and my son got fourth only to find out lightened wheels were probably what beat us. This year we lightened the wheels and spent more time on wheels in general, used a more agressive COM and drift and my son got 1st. First Rail rider will give you a baseline for your next car. Don't give up on it. It's what the pros do...but they do it MUCH better.

Was your rear wheels aligned that they stay off the rail? Where was your COM? How much drift did you have before and after the race? Did use positve cant on the front wheel? What was your bore prep and lube procedure? Many things could contribute to a sub par rail rider. Without knowing everything that a person has done it is hard to give suggestions.