Dismiss Notice
Welcome to
Pinewood Derby Online, a forum for questions and discussions about everyone's favorite gravity powered racers!
CLICK HERE to register as a member today for full access to the forum, it's fast, simple, and absolutely free!

Wheel Gap Question

Discussion in 'Ask The Pros' started by Prozach2, Feb 4, 2021.

  1. Prozach2

    Prozach2 Workshop Leader

    Messages:
    166
    Likes Received:
    82
    Trophy Points:
    28
    Gender:
    Male
    Location:
    Charlotte
    DFE7BD21-E9D6-46F7-AAD0-62FE78124283.jpeg
    I bought the Owen’s Wheel Gap Gauge from DD4H. Do any of you use it? Do you have suggestions on the ideal wheel gap(s)?
     
  2. Hangtime

    Hangtime Pinewood Ninja

    Messages:
    40
    Likes Received:
    15
    Trophy Points:
    8
    Gender:
    Male
    Location:
    Iowa
    I’m sure others will weight in shortly, but I’ll share what I’ve learned. The amount of gap needed will vary based on how well your axles fit your hubs. The goal is to have enough gap so that your wheel won’t bind between the body and axle head when it wobbles to its most extreme angle. Closer tolerances between axle and hub allow for very tight gaps - maybe as small as .005. Sloppy tolerances may require.020 or more. A tuning board will help you figure out what works best for you.
     
    Prozach2 likes this.
  3. Loud2ns

    Loud2ns District Champion

    Messages:
    127
    Likes Received:
    93
    Trophy Points:
    28
    Gender:
    Male
    I would probably with the .007 one.
     
    Prozach2 likes this.
  4. T-Bone Racing

    T-Bone Racing District Champion

    Messages:
    111
    Likes Received:
    80
    Trophy Points:
    28
    Gender:
    Male
    Location:
    New Jersey
    To be completely honest, all of my cars take different gaps. Most of them seem to be relatively tight, but some I keep loose, because they don’t run well with tight gaps.
     
    Prozach2 likes this.
  5. Prozach2

    Prozach2 Workshop Leader

    Messages:
    166
    Likes Received:
    82
    Trophy Points:
    28
    Gender:
    Male
    Location:
    Charlotte
    6AD3C1FF-F84A-43B5-8C1A-EC675054A0D0.jpeg
    My body broke when I tried to push in the axle. It also cracked on the back axle. I’m going to cut another body today and leave more meat on the car. Are there any other tips/thoughts for pushing the axles in or drilling the holes? I’m using the silver bullet extreme and a hand drill to drill the holes. DD4H has a video. I’m basically doing it just like that. I was wondering if I should maybe go back and forth with the drill or something. It feels like I’m having to push the axles way to hard to get them to go in.

    Thank you to everyone for your help!
     
  6. T-Bone Racing

    T-Bone Racing District Champion

    Messages:
    111
    Likes Received:
    80
    Trophy Points:
    28
    Gender:
    Male
    Location:
    New Jersey
    For your back axle brace, but a piece of 1/64 inch birch plywood on each side, and that’ll help protect it. You can probably go back in forth with the hand drill, but carefully! Do you have slots cut in the axle heads for tuning?
     
    Prozach2 likes this.
  7. Prozach2

    Prozach2 Workshop Leader

    Messages:
    166
    Likes Received:
    82
    Trophy Points:
    28
    Gender:
    Male
    Location:
    Charlotte
    Thanks T-Bone. I have a slot and a 3 degree bend in the FDW axle. No bend or slots in the other axles. I've got plenty of 1/64" birch, so adding that shouldn't be a problem. II had some hairline cracks in the rear axle also. I wasn't worried about the front axle b/c it's easy to make that wider. But, if I make the back axle any wider, the the tungsten cube will stick out. I was thinking about glueing that tungsten cube into place before I pushed in the axles. That would probably give it more stability.
     
  8. Dldoug

    Dldoug Rail Runner

    Messages:
    91
    Likes Received:
    46
    Trophy Points:
    18
    Gender:
    Male
    Location:
    Virginia
    I’m not a pro by any means, but if you make another body I would relax the holes by installing axles before cutting it into a ladder. Install a couple times in each hole then cut out the weight. My two cents which have worked for me.
     
    ScoutDad11, Eric Scheid and Prozach2 like this.
  9. Prozach2

    Prozach2 Workshop Leader

    Messages:
    166
    Likes Received:
    82
    Trophy Points:
    28
    Gender:
    Male
    Location:
    Charlotte
    I'll definitely try that. Thanks!
     
  10. Loud2ns

    Loud2ns District Champion

    Messages:
    127
    Likes Received:
    93
    Trophy Points:
    28
    Gender:
    Male
    I have used an old axle with the head cut off and put it in a pin vise to relax the holes.
     
    Prozach2 likes this.
  11. T-Bone Racing

    T-Bone Racing District Champion

    Messages:
    111
    Likes Received:
    80
    Trophy Points:
    28
    Gender:
    Male
    Location:
    New Jersey
    Another thing you could try is putting an axle into a pair of axle extraction pliers, and slowly twisting in and out of the hole. I’ve probably done that to all of my cars at least once.
     
    CastleCrasher likes this.
  12. Prozach2

    Prozach2 Workshop Leader

    Messages:
    166
    Likes Received:
    82
    Trophy Points:
    28
    Gender:
    Male
    Location:
    Charlotte
    LOL, had no idea there was such a thing as "axle extraction pliers". I'm assuming that's something I'd have to order from a pinewood derby website right? Or is that something I could get at a hard wood store. I was kinda wondering how I was going to get those axles out w/o damaging them or the wheels. I don't mind cutting another body, but I don't have time to prep more wheels and axles.
     
  13. T-Bone Racing

    T-Bone Racing District Champion

    Messages:
    111
    Likes Received:
    80
    Trophy Points:
    28
    Gender:
    Male
    Location:
    New Jersey
    Prozach2 likes this.
  14. Brian Stanley

    Brian Stanley Workshop Leader Pro Racer

    Messages:
    197
    Likes Received:
    152
    Trophy Points:
    43
    Gender:
    Male
    Location:
    Charlotte, NC
    Relax the holes using an old axle and a pair of needle nose pliers. I have a set of the axle pliers but don't use them on prepped axles as they can damage the underside of the head.
     
    Eric Scheid and Prozach2 like this.
  15. Prozach2

    Prozach2 Workshop Leader

    Messages:
    166
    Likes Received:
    82
    Trophy Points:
    28
    Gender:
    Male
    Location:
    Charlotte
    My plan is as follows:
    1. Drill two blocks and put some unprepped axles in the holes.
    2. Cut up the body that cracked and try to push those axles out w/out damaging them or the wheels. No big deal if I mess them up b/c I have another prepped set that's untouched. Those will go on my younger kid's car that is competing for a certificate in the "sibling race".
    3. Cut and assemble two new bodies.
    4. When I put the prepped wheels and axles in, I'll leave more gap than I need.
    5. Brian, when I bring the cars up to your house to test them out, can you help us find the ideal steer and wheel gap?

    I got you a small gift to show my appreciation. :D
     
  16. Brian Stanley

    Brian Stanley Workshop Leader Pro Racer

    Messages:
    197
    Likes Received:
    152
    Trophy Points:
    43
    Gender:
    Male
    Location:
    Charlotte, NC
    Yep, we'll get it sorted!
     
    Prozach2 likes this.
  17. Prozach2

    Prozach2 Workshop Leader

    Messages:
    166
    Likes Received:
    82
    Trophy Points:
    28
    Gender:
    Male
    Location:
    Charlotte
    67F5B5C1-AB0E-44FE-BDFC-97636DA219FB.jpeg
    FBD05C30-9334-4CEC-B624-3EED97F50BAC.jpeg
    We made three ladder bodies and all three broke when we put in the axles. So, we made two more last night. We put axles in the axle holes right after we drilled it (before cutting and sanding the bodies). We also increased the rib for the front axle from 1/4” to about 5/16”. That did the trick.

    Thanks for the help guys!
     
  18. Dldoug

    Dldoug Rail Runner

    Messages:
    91
    Likes Received:
    46
    Trophy Points:
    18
    Gender:
    Male
    Location:
    Virginia
    They look great, glad it worked out!
     
  19. Prozach2

    Prozach2 Workshop Leader

    Messages:
    166
    Likes Received:
    82
    Trophy Points:
    28
    Gender:
    Male
    Location:
    Charlotte
    Thanks! The race is Saturday, so I was starting to get nervous.
     
  20. Mojo Racing

    Mojo Racing National Contender Pro Racer

    Messages:
    942
    Likes Received:
    499
    Trophy Points:
    63
    Location:
    Uniontown, OH
    Hey guys,

    A couple of things... If you use poplar to make your car bodies, it will cause the axles to feel very tight when inserting or extracting them. varieties of pine will make it much easier to install or remove the axles.

    Also, ensure you are using a #43 drill bit when drilling your cars. This will allow your stock axle to easily go in as well. There are places in the forum that say #44 for scout, but I feel that is too tight, and you will end up doing more damage than good.

    You should be able to push your axles in with your fingers.

    :cool:
     
    Last edited: Feb 5, 2021

Share This Page