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4 on the floor rail rider

Discussion in 'Ask The Pros' started by DuckOfAllTrades, Feb 5, 2019.

  1. DuckOfAllTrades

    DuckOfAllTrades League Racer

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    Adult District, and my kids races, don't allow three wheel rail rider, 4 have to touch. To get around this, I've been trying to come with a solution as to how to accomplish this. I've read a lot on the internet and forums, internalized them all and came up with a solution I felt wouldn't be too difficult or complicated for me. Something I could easily replicate across a few cars. Here's my setup:

    Back wheels straight axles (not suppose to bend axles on my kids! I can however, so this just applies to there. I plan to go full out bent axles all around on my car.) I installed one front axle, straight. The other axle stock but a little warped/defective. Not a perfect axle and that gives me drift if I turn it (hope I can find more of them in my stock). I installed the straight back axles and the front left dominant wheel with the bent axle. I tuned the car so it gave me about 3 inches of drift, best I could get without bending further (May have to accidentally drop a hammer on it or something!). Once I got that setup, I glued them in place so they would not move. Let it dry, installed the right front wheel. I worked on the wheel/axle in the groove (have to use them), pushing it up until it was slightly pointed upwards, barely touching, but turning and "on the floor." Floating as they say. I glued this in place so it wouldn't turn. Let it dry, then tested, and it worked perfectly. Retained the drift with the new wheel in place. I spins when you move the car back and forth, so they can't say it's not four on the floor. They test by placing it on a flat, hard surface, I believe marble, and roll. If it rolls, it passes and this wheel does.

    My question is this: Is this a horrible design't destined to fail? Will the front floating wheel or back straight axles be a detriment, and destroy the idea of a rail rider in the first place, defeating the purpose.

    If that's the case, I should probably give it up and go full out straight run.

    And if anyone else has any other ideas I can use to accomplish this or to improve on my design, I'm all ears and would appreciate it. My goal is to max out every advantage within the strict rule set.

    Thanks in advance!
     
  2. DerbyDad4Hire

    DerbyDad4Hire Administrator Staff Member 25+ Pro Race Wins! National Champion

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    4 Wheel Plug N Play. Simple and extremely fast. Always Rail Run!
     
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  3. DuckOfAllTrades

    DuckOfAllTrades League Racer

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    Hi Derby Dad. That's what I've heard. I ordered a few cars/blocks from you the other day. Unfortunately, we have to use the stock groove. Lame, right?

    Or I should say at district level. I plan on building out one of your 3 wheel RR to hopefully cream the competition in the adult race! Can't wait til it gets here.
     
  4. DuckOfAllTrades

    DuckOfAllTrades League Racer

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    I should add, if you DO offer a 4 on the floor RR that uses stock slots or could create one, I'd be happy to purchase one.
     
  5. TRE

    TRE PWD Royalty Pro Racer Pro Race Winner

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    You can cut your own slots john can cut them for you when you order it
     
  6. DuckOfAllTrades

    DuckOfAllTrades League Racer

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    Awesome. I ordered three. Two that I ordered, I had him cut the slots. Will the wheels go in those slots, or holes above? They have to actually be in the slots. If the slots are actually used, I'm golden!
     
  7. DuckOfAllTrades

    DuckOfAllTrades League Racer

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    Has anyone had any luck angling the axles in the stock slots without bending the axles? Wonder if there is a way to do this. I'm sure it would be super tough to get an accurate degree of bend though. If anyone knows of a way or has any ideas, let me know. I may try to glue in a tiny strip of business card, or two or three layers, towards the end of the axel in the slot in hopes that the tip will rest on it and the back coming out the slot will rest on the wood and give it a slight angle. It's just being able to repeat the same angle on all four sides. This would allow for canted axles where rules prohibit bending and using new holes.

    Guess you could eyeball it too and pull the axle upwards, but sounds really inexact and you'd have to get lucky to get the results desired.
     
  8. Joe

    Joe Bent Axle

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    Duck, drill your holes using your jig and then cut slots to match. There are a variety of ways to do it, but if you have two left hands, it is my understanding you can use something like a Stanley miter saw box to help. (15 bucks at the blue borg, includes the saw which matches original slot width). shopping.png
     
  9. cara424

    cara424 Pinewood Ninja

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    Can someone explain how to create a railrider? I mean what is the drift you need to have? And is this a better setup than going straight for the cubs? Or is it to difficult to achieve with 4 wheels?
     
    Last edited: Feb 12, 2019
  10. DuckOfAllTrades

    DuckOfAllTrades League Racer

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    Are you allowed to bend the axles? It depends on your rules. I can tell you how I did it, but it’s without bent axles. If you can bend axles, you have a few options.
     
  11. cara424

    cara424 Pinewood Ninja

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    No, can’t bend axels in cubscouts
     
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  12. DuckOfAllTrades

    DuckOfAllTrades League Racer

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    That makes it tough. You are probably better off getting it to run straight is possible. What I did was use the defects in the axles to gain a little drift by finding the least straight axle I could. But I had at least 100 to sort through. Chance are, right out of the box, you aren't going to get too much of a bent axles.

    Another possibility is the axle slot. I have NEVER seen a straight one! They are always veering, which makes it tough if you can't bend the axles. But it could work to your advantage. If you find one that drifts 4 inches or so. What I would do is insert the back wheels and one front on one side. See how much it drifts over 4', If it gets close to 4", that would be awesome. If not, take the wheel out and place it on the other side. See if it drifts or what it does.

    Then what I would do is if you have a side that drifts, make that your dominant wheel. Insert the other axle and see what you got. Chance are, one is off the ground. I see a lot of BSA kits where this is the case and it's a royal pain to get all four touching! Use that to your advantage. Work on the wheel and get it touching, but just barely. If it does touch and is solid, work on the wheel til it "floats." That is when you roll the car, it rolls, but spin it with your finger and it should turn pretty freely. You want it to roll with the car but barely barely touch. That way you have a dominant wheel, and non dominant wheel. Should pass inspection, but make sure to try it out on a hard flat perfect surface to be sure. It may roll on a non perfect surface, then not roll on the hard perfect surface.

    Hope all that makes sense.
     
  13. cara424

    cara424 Pinewood Ninja

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    So, sounds stupid... but how do you recognize that your axel isn’t straight? They sll look the same to me even after looking closely. By accident, I had a “floating” wheel last year and it didn’t pass inspection at worlds.

    What’s the difference between making a rail runner and your car not running straight just by slapping the axels in?
     
  14. DuckOfAllTrades

    DuckOfAllTrades League Racer

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    It's hard to tell as they are just BARELY bent. I take them in my fingers and roll them, comparing two at once. But the best way I've found it to put them in a drill press! Put them in a drill press, turn them on, and if it's out of shape/bent, it will wobble.

    I'm not sure the answer to your second question. I've questioned this for a long time! I call it a "natural rail runner." If it does this out of the box, will it work? Or do you have to have a bent axle. My inclination is to think if it does turn automatically, you can take advantage of it. BUT the dominant right wheel would have to be turning left, or the dominant left to the right. Otherwise it's just going to ride the outside of the rail. But if you did hit it just right, float the other wheel and I bet it would work. To determine which wheel is turning the car, insert one front wheel and the two back and see what happens.
     
  15. cara424

    cara424 Pinewood Ninja

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    So what is the definition of a dominant front wheel? And if say the right front wheel is causing the car to pull right, it is not a rail runner? And Am I correct that the back wheels need to be straight?
     
  16. DuckOfAllTrades

    DuckOfAllTrades League Racer

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    Correct. If you think about it, if the right front wheel is pulling right, it's not riding the inside rail, it's going the opposite way, make sense?

    The dominant front wheel is the one that bears the most weight, touches the ground the most, is the most influential in direction. The one that controls the steer. Someone may know better than me on this! So I'd rather a pro define it, as I may be wrong. I create a dominant front wheel by raising the other wheel slightly. Make sure it still rolls when you car rolls! Most rules allow for this, it simply has to touch, and at inspection they will place it on a slab of marble or hard surface, and roll it. If it rolls, your good, even if it's floating a tiny bit.

    And yes, the back wheels do need to be straight. Otherwise they are scraping the rail and slowing you down. I think this can slow you way down, but again, a pro would know better than me.
     
  17. cara424

    cara424 Pinewood Ninja

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    So... 2 questions... could you insert your acel at an rear angle rather than bend it to get the steer and could you put a little putty weight on that side to help it?
     
  18. DuckOfAllTrades

    DuckOfAllTrades League Racer

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    I’m not sure about the putty weight question, some one would know much better than me about weight distribution.

    As far as angling, my understanding is it’s best to put the axle in at an angle rather than bend. I imagine it’s more precise. But to do this, a jig is a must. You can’t drill them or angle them without it. You would end up with the wrong angle and different angles on different sides if you did this, unless you got really lucky! They need to be at the same angle and at an angle it would be hard to guess at. Make sense?

    Also, you don’t want the back axles to steer, that’s the fronts job. You want them to ride away from the car, with the front giving you the correct steer. If done right, they shouldn’t touch the rail. Shaving 1/32 off the steer wheel helps with this.
     
  19. cara424

    cara424 Pinewood Ninja

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    So if you’re inserting the front axle at an angle is that still complying with the rules of using the original axle slots and how do you prevent that angled wheel from rubbing against the side of the car if you can’t shave down the wheel of it
     
  20. DuckOfAllTrades

    DuckOfAllTrades League Racer

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    Technically speaking, inserting at an angle shouldn’t violate the rules. The trouble you’ll have is getting the right angle. You’d just be guessing. Plus to get the right angle to get the correct steer, you couldn’t just insert it into the slot, you’d have to find a way to angle it in a little too. I wouldn’t recommend as most likely you’ll make yourself slower rather than faster.

    While shaving the body does seem illegal, it can be within rules. Most likely your rules state your car must be 1 3/4 inches wide says nothing about shaving the body. If you shave 1/32 from one side and add 1/32 to the other side, it’s stikl the same width and within rules. I did this for our tech day and it worked well. Our car was noticeably faster than the other cars, but it has to be a rail rider to make a difference.
     
    Last edited: Feb 18, 2019

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