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My 10 year old son and 8 year old daughter have cars competing in a pinewood derby tomorrow night. They've got the cars cut and painted and I'm going to put the wheels on and add some weight tomorrow. I plan to drill some holes in the bottom and glue in some 148g .358 wadcutters that I recently cast.
Any advice on where to place the lead from front to back and if it's good to keep it low on the car for a low center of gravity etc. Any tricks to putting the wheels on for a faster time? We are allowed to use powdered graphite or silicon for a wheel lube. Car can weigh 5 ounces.
My daughter's is close to weight already with all the heavy purple candy like paint and her huge hood that looks like a 77 Buick. She only needs one 148g wadcutter. My son's more aerodynamic boattail design is going to need four 148g wadcutters.
Grandpa helped my daughter with the Buick but who knows, it'll probably win. I cut my sons car with VLD principles in mind and went for high BC. I just need to get the weight distributed right.
Bb
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Get it rolling on 3 wheels.... Polish axles to a mirror finish.
Last edited by Featherweight6555; 11/08/22.
"Aim right, squeeze light" " Might as well hit what you're aiming at, it kicks the same whether you miss or not" NRA Life, GOA
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Campfire Kahuna
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Campfire Kahuna
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I couldn’t complete with the guy who had an Aerosoace team build his kid’s car
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Campfire Sage
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Campfire Sage
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My 10 year old son and 8 year old daughter have cars competing in a pinewood derby tomorrow night. They've got the cars cut and painted and I'm going to put the wheels on and add some weight tomorrow. I plan to drill some holes in the bottom and glue in some 148g .358 wadcutters that I recently cast.
Any advice on where to place the lead from front to back and if it's good to keep it low on the car for a low center of gravity etc. Any tricks to putting the wheels on for a faster time? We are allowed to use powdered graphite or silicon for a wheel lube. Car can weigh 5 ounces.
My daughter's is close to weight already with all the heavy purple candy like paint and her huge hood that looks like a 77 Buick. She only needs one 148g wadcutter. My son's more aerodynamic boattail design is going to need four 148g wadcutters.
Grandpa helped my daughter with the Buick but who knows, it'll probably win. I cut my sons car with VLD principles in mind and went for high BC. I just need to get the weight distributed right.
Bb Skip the derby. Take your son and daughter to a bar. Read them passages from Iceberg Slim's autobiography. Far better use of your (and their) time.
Trump being classless,tasteless and clueless as usual. Sorry, trump is a no tax payin pile of shiit. My young wife decided to play the field and had moved several dudes into my house
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Joined: Mar 2020
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Campfire Member
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Back 40 plus years ago we would use dry graphite on the axles, and spin them for hours to polish everything up. We would sand the parting lines out of the tires, and make sure the car sits on all 4 wheels evenly. We always kept the weight low. We would fine tune the weight with a couple small screws underneath that could be removed if it was overweight once you got to your race. We kept the weight centered in the car. When in Boy Scouts I won the whole damn shooting match. And no, my dad did very little on the car. He told me what to do and watched but I did it as per the rules at the time. Fun for all!
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Campfire Ranger
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Biggest letdown of my childhood was when I realized that the Pinewood Derby was actually about the dad's skill and not the kids, who were supposed to be building the cars.
4 out of 5 Great Lakes prefer Michigan.
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Campfire Tracker
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There are jigs that allow you to raise one of the front wheels up (so you run on 3).
The jigs also allow you to drill the axle holes in at an angle, so the wheels run on knife edge (inner edge).
Polish the axles, or buy better ones. Graphite the heck out of the wheels. They sell better wheels, as well, that are still “stock”.
Lengthen your wheelbase (rear wheels can stick out past rear of car. Do NOT extend front wheels past front of car they will get damaged if the car hits something).
We would drill out a cavity in the back of the car. Fill in with lead shotgun shot until we got the weight of car/wheels/axles up to about 4.9 oz. Use wood putty to fill in the cavity at that point. Balance point of car should be about 1/2 inch to 1 inch in front of rear axle.
You can lay the body of the car on a pencil, to see where it balances.
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Campfire Kahuna
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Campfire Kahuna
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I couldn’t complete with the guy who had an Aerosoace team build his kid’s car Lol...that was me. I was lucky enough to to have a dad that let me lose. A lot.
The only thing worse than a liberal is a liberal that thinks they're a conservative.
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Campfire Ranger
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Pinewood Derby Champion 1971 checking in.
AMA
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Campfire Tracker
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My opinion is you could try letting the kids build a car more or less the way they want, and not worry about applying all the ‘tricks’ in the book to ‘win’. Ask the 10 year old where *he* thinks you should put the weights. Let him design the shape and apply a cool kid paint job.
Or you could buy a 3-axis cnc machine to mill out the body, polish the axles with diamond dust and coat them with the finest graphite you can find so your kid can learn all about ‘winning’.
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Campfire Kahuna
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Campfire Kahuna
Joined: Jan 2012
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I watched a kid one time, open the package, take the block, add the wheels and tape .75 cents on top
And he won 2nd place
The team of 23 Nasa aerospace engineers still took 1st with the little coke bottle glasses kid that smelled like pee
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Campfire Outfitter
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Good Luck to them Hope they Place high
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Campfire Tracker
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Put the weight at the very back of the car. In fact, lighten up the front as much as is practical. The higher the center of gravity, the more potential energy, ie, the car ‘falls’ farther = more speed. Physics 101
Bevel inside of wheels so only the inside touches the body of the car. Do the same with the axles - bevel the outside so it doesn’t touch the wheel except at the very inside. Easily done by chucking the nail in a drill and dressing it with a file. While you are at it, polish the axle shafts.
You can narrow the ‘tire’ surfaces but it may get DQ-d depending on the refs. As someone mentioned above, set it up so only one front wheel is on the track. 3 wheels are less friction than four. Make sure the car rolls straight.
Yours in Liberty,
BL
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I let them draw the design they wanted on the car and then we cut them to theirs specs. They did all the sanding and painting themselves. That's how we ended up with a hard candy purple 77 Buick but I figure it's her car she can do it her way.
I'm in charge of putting the lead weights in so that's why I need tricks in placement and balance etc. I'd heard of the running in 3 wheels trick and I chucked some axles in a drill and tried to polish them down. I honestly think the stock axles without my polishing run smoother. The hot dipped zinc like finish seems smoother and they don't wobble as much as the slightly polished down ones.
I'll look into running the wheels on the inside edges and get some powdered graphite tomorrow. Sorry to bring back painful childhood memories for some of you.
Bb
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Joined: Nov 2018
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Campfire Ranger
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Campfire Ranger
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Drill holes in the back and bottom of the car and melt lead into the cavities. Cover with putty and on race day drill out lead until you make weight.
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I use o-rings on over each wheel to cut down on friction
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Old guy, old guns.
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Campfire 'Bwana
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Interesting video and ideas. I was surprised by how short the length of the track/race was.
Make Gitmo Great Again!! Who gave the order to stop counting votes in the swing states on the night of November 3/4, 2020?
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