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Captnmrgn23

Hammering Axles
Apr 22, 2018
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I have my daughters powder puff derby next saturday. Rules state no bending axles, grooves, or altering etc. Basically besides knocking the burrs and sanding we can't do much. Same with wheels. Light sanding. No turning of any kind and pinecar brand wheels must be used. Besides, adding weight, polishing inside the wheels, and polishing the axles, what else can be done? Whats a good time to shoot for? Going to practice run on a friend of a friends home track. I believe its 42 feet . Any help would be greatly appreciated as this is my first time running or making one of these....
 

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We had our districts Sunday
Our car meets your rules and we ran 3.101 on a new 42 ft track ended up 2 nd place
It ran 3.041 on our packs 42 ft track ended up 1st place
Make sure you put graphite on the axles
Hope this helps
 
Did a couple more things and will retry tomorrow. Machined some new axles at work. A little bigger definately straight. I heard the track we will be using isnt the best so will have to see how it works out. I think I can get it under 3.2 adjusting some things. We shall see. Thnx
 
Did a couple more things and will retry tomorrow. Machined some new axles at work. A little bigger definately straight. I heard the track we will be using isnt the best so will have to see how it works out. I think I can get it under 3.2 adjusting some things. We shall see. Thnx

You haven't gotten a lot of responses, not because there isn't good information here, rather your rules and what you already had done limits what can still be done.

The reply about a Plug and Play drill job is spot on!!! Keep that in mind for next year. If you don't understand it, ask questions.

Ok, for now ... if you don't have DD4H's graphite then go find yourself some HOB-E-LUBE. Yes it does and will make a difference! Now is the perfect time to switch it out as you have some new axles. Look up burnishing. Burnish the wheels bores and the inner and outer hub surface. Also burnish graphite into the side of the car where the wheel hub will touch.

Last thing before you head to the race is to be sure that you clean the wheels! Clean wheels can be worth over 0.010. There are several methods if cleaning them. Look up on You tube for Joel's video on cleaning them. 1000 grit sandpaper or a nail file block both work well. With the nail block you will only use the last 2-3 steps depending upon how many it has and how course they are.

Do a BUNCH of reading before next year and don't be afraid to ask questions before you start and/or early in the build.

Good luck with your race!!! Remember to have fun!
 
Had my wife hunt down some in hob-e-lube...went dowm the rabbit hole now...This was thrown at me in the beginning of march as my daughters troop is new and her leader isnt really on the ball when it comes to information. So really only had a little over 4 weeks to prepare once we received the cars. Polished the axles to a shine. Did the plastic polish in the bores but decided to do more wheels that I had and pick the best ones and matched. Polished hubs at work. Moved up front wheel so it rides on 3 now and should ride the rail...Adjusted the weight back a bit closer to axles. Will test tonight and see how she runs. Didnt think there was this much involved in a wood car race. But my buddy told me I wouldn't be able to place. Challange accepted...Thanks
 
You have just scratched the surface ....

Depending on your track and if you are able to adjust the DFW (the one that rides the rail) to steer into the rail, a good starting amount is approximately 5"-6" over a 4' distance. I know that sounds like a lot and seems counterintuitive, but the drag from rubbing the rail is WAY LESS than if the car wiggles. Each time it wiggles will cost you about a hundredth. 2" too much steer may cost you 2-3 thousands.

Remember to burnish the inside edge of that DFW also as it will be riding up against the inside guide rail (assuming you have a center guide rail style track).

Most people at scout level will polish the axles to 2000 - 3000. They can be polished all the to 12,000. There is diminishing returns above the 3-5000 range.

Check your rules ... if they don't say anything about silicone, try this. Before you install the axles, wipe them down with lemon pledge. Let them sit for a few minutes, polish them with a clean cloth and them assemble. Our rules don't allow silicones, so we do not use the Lemon Pledge. Instead we use a product called SailKote. It is a dry lube and is legal by our rule set.

Every little thing adds up and can help. Right now, Hob-e-lube, pledge, burnishing the wheels and side of the body along with setting the steer will gain you the most.

Good luck and let us know how it goes!
 
S7 steel axles
Cnc ground
Did all the rest. Testing later tonight. Then its in the hands of gravity...and 7lb 2oz baby jesus...lol...Turn in is about that maybe a little less....Ill let you know and thanks for the help and ideas...
 
Alot of slow cars. Next fastest was 3.278. Some didnt even run the whole track....

Ours
3.0898 , 3.0989 fastest
Avg-3.1133 avg
And she got her trophy....
 
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