Placed second, Again! Please help

Dcurry

Dcurry

Bent Axle
Apr 9, 2019
12
8
3
41
Iowa
For the past two years my son's car has placed second at our pack race. I came across this site after last year's race. I vowed that we weren't going to come in second again. I read and read and read the posts. I watched as many videos as I could.

I bought the silver bullet extreme to drill our axle holes, I got the BSA extreme axles, the mid America wheels. We sanded the axles from 1000-7000 grit sandpaper paper then did the next level polish. I got the black ice wheel bore prep and derby dad graphite.

I built the the jigs from bulldogs video, and we made our body lightened to just under 9 grams. We cut the weight pockets and got about 4oz of tungsten (12 cubes behind the and 11 right in front of the axle.

We used the gee fenders and trailing fenders. We tested it on our makeshift tuning table and had about 4" of steer over 4'. We drilled the back axles at 3° and used a bent front axle with positive cant.

After all of that, we finished in second again...

My son finally beat the kid that he lost to the last two years, but another kid ended up coming out of nowhere and beating us by almost a full 0.1 second. We have a 4 Lane 49' aluminum besttrack.

I am just curious if anyone has any suggestions that we could change before our district race.
 

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Seems with mid america wheels and a 9g body you should have been able to add more than 11 cubes in front of the axle. Maybe the paint or the fenders are heavyish?

When you drilled the car with 3 degree cant did you keep in mind that the bend of the front axle will raise the front of the car? And with that in mind the height of the holes needs to be so that when the bent axle is in place the body needs to be level. If it is up in front then it is catching air and also the rear's will be towed out slightly.

Are u using graphite or oil? If you are using graphite and your opponents are using oil you are at a sizeable disadvantage.

Are your opponents using lighter wheels than MA wheels?

I cant tell in the picture but did u use air shields? Another disadvantage if your opponents are using them.

Custom shaped fenders from balsa are better than the gee fenders.

Scott
 
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I am by no means a pro, and have only done scout level racing but a few thoughts...
- the gaps on the rear look large - which can cause wiggles
- the rears do not appear to have any noticeable cant - maybe its just the angle
- also no noticeable cant on the DFW
- if you are prepping your own wheels, it is fairly easy to enlarge a bore, and I'm guessing it is even easier to do on a lightened wheel like you are using
- maybe the weighting was also too aggressive for a derby track and could have used more steer - I aim for about 6-7 inches over 4 feet on our scout track as the transitions are not smooth

Anyway, just my .02. Did the car appear to run smooth? More pics would also be helpful - from the rear, directly from the front, etc.
 
Thanks for the replies... I will take it all into consideration and start checking some of these items.

A few answers to your questions.
- I forgot to mention that I have 11 cubes plus about a cubes worth of tungsten putty in front of the axle. I wanted the putty so I could adjust the weight at check in, my scale is always a little off from the official scale. Plus my son really wanted to make his car look like the '66 GT40, so that took a few more coats of paint than I really wanted to add. But it is his car, so I let him decide that.

- thanks for the tip on checking for level with the canted rears, I didn't even realize that. How would one go about drilling the holes with the SBE to make sure the holes will be level when using the bent front axle? I didn't see anything from John about that in his video. Would you need to shim slightly before drilling?

- we are required to use graphite. I used the derbydad graphite, and we tried to get it worked into the bores and we spun the wheels on the axles several times before installing on the car. I know the dad of the kid that beat my son, and I am fairly confident that they wouldn't break the rules and use oil.

-the kid that beat our car did have wheels that looked like they were lightened significantly, but I don't know if they were lighter than the mid America wheels, these are pretty light...

-we did not use air Shields, those I am fairly unfamiliar with, and will need to do some more research and reading here about. But, nobody at our pack had those either, so that may be one more thing to help us with an advantage.

- our gaps may have been a little large, I was slightly concerned about that, I didn't have any kind of guage so I just went with what I thought looked ok, I was just afraid of getting them too tight and having them rub.

- actually our car ran really smooth down the track, I was almost worried that I put too much steer. It didn't wobble or bounce or anything. Just straight down the rail.

Thanks again for the replies, I truly appreciate them and will use them to try to help my son improve his car.
 
Is there any chance that you are up against 5KidsRacing ?

Maximum Velocity (YouTube) has a good video on graphite application.
 
No, not 5KidsRacing, it's actually a scout dad and it's only their second build. His son is only a Tiger.

Thanks for the tip on the YouTube video for the graphite, I will definitely check that out.
 
That would be amazing. I would love for you to take a look and let me know. Should I message you directly for details about sending it?

Thanks
 
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You said your rear wheels were canted by 3 degrees. If the photo is of the top of the car, it looks like bottom of the wheels are canted in rather than out. If that's true, that would definitely affect your speed. It could just be the fenders throwing me off. Could they have potentially run it upside down?
 
Craigs Cruzer said:
You said your rear wheels were canted by 3 degrees. If the photo is of the top of the car, it looks like bottom of the wheels are canted in rather than out. If that's true, that would definitely affect your speed. It could just be the fenders throwing me off. Could they have potentially run it upside down?
Click to expand...

Well, I used the silver bullet and I drilled in the 3° bushing. I'm wondering if maybe my wood could have bowed or warped or something. I'm not sure. I apologize, I didn't upload a very good picture. For some reason that is the only one I have in my photo gallery on my phone that the site will let me upload. Everything else I try says that the photo is too large for the server.

It definitely wasn't run upside down, I was there handing cars to the guy that was staging on the track.

Thank you for the reply
 
Dcurry said:
Well, I used the silver bullet and I drilled in the 3° bushing. I'm wondering if maybe my wood could have bowed or warped or something. I'm not sure. I apologize, I didn't upload a very good picture. For some reason that is the only one I have in my photo gallery on my phone that the site will let me upload. Everything else I try says that the photo is too large for the server.

It definitely wasn't run upside down, I was there handing cars to the guy that was staging on the track.

Thank you for the reply
Click to expand...

Last year, they put our car on the track upside down at council. We had sanded all the paint off to make weight, so it was hard to tell. Fortunately, I caught it before it went down the track. I ran over and wrote “TOP” and “BOTTOM” on it.
 
Couple extra thoughts:
1) Increase level of sandpaper to 10000 or higher
2) graphite and CA at axle holes. Sand until really smooth
3) add Pledge or Sailkote as final step to axle prep
4) Take Derby Dad up on his offer. He may catch something just by handling it.
 
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Craigs Cruzer said:
Couple extra thoughts:
1) Increase level of sandpaper to 10000 or higher
2) graphite and CA at axle holes. Sand until really smooth
3) add Pledge or Sailkote as final step to axle prep
4) Take Derby Dad up on his offer. He may catch something just by handling it.
Click to expand...

Thanks for tips. I will get some higher grit sandpaper for the next round.

I need to look into doing the graphite and CA to the axle holes. I forgot to add in my original post, I tried the clear coat fingernail polish with Hardener. Let it set up then I sanded and coated with graphite, not sure how well we did with that.

I said also forget to mention, we did use the lemon pledge as the final step after the next level polish.

And yes, I plan to send to John, that was an incredible offer he made to take a look and o would be an idoli to pass that up.
 
Were you running with 3 wheels touching? If so, did you weigh the car on 3 individual scales (1 wheel on each scale) to try to balance the weight distribution? Were your tires clean and inside edge of DFW coated with graphite? Also, make sure you cut the DFW side in by 1/16" for rail rider.
 
Craigs Cruzer said:
Were you running with 3 wheels touching? If so, did you weigh the car on 3 individual scales (1 wheel on each scale) to try to balance the weight distribution? Were your tires clean and inside edge of DFW coated with graphite? Also, make sure you cut the DFW side in by 1/16" for rail rider.
Click to expand...

We did run on 3 wheels, I did not weigh on 3 scales but that is something I will need to invest in now. What exactly are you looking for on each scale, do you want to be heavier on the DFW side, or balanced? We did clean the treads right before we checked the car in and we tried coating the inside edge of the DFW with graphite, not sure how successful it was.

Before paint we did sand down the DFW side of the car, I think we were a bit shy of 1/16" and I think it got reduced even more with the coats of paint we applied. Lesson learned for next time. I tried talking my son in to just using vinyl, but he really wanted that paint job.
 
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