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Pinewood Derby car help!!!!

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Okay, I am actually part of the boy scouts, but our cub scout pack invited our troop and leaders to participate in the derby. I have never built a car before and I am kinda on my own. I only have til friday to finish. SO here are my questions: Do you have to prime the car before you paint it? You glue weights on it after you paint, right? The wheels go last? I just want to be sure I am doing everything right. Right now I already sawed into my shape, and I am sanding at the moment. Any advice???

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Make sure your car is fully shaped and sanded. Sanding is the most painful part but makes the difference on how the car looks. Paint really highlights rough spots.


At this point you should find out how much your car weighs. Use a scale that measures in 1/10th or preferrably 1/100ths of an ounce. Use the Pack Official scale if possible but if not use your own (making sure it zeroes out when nothing is in the pan). To weigh, just set the car body, wheels (unattached) and 4 nail axels on the pan. Object is to get as close to 5oz as possible (without going over).


I find that I add weight at this point - before painting. Most of the time I am drilling a hole in the bottom of the car and that screws up the paint. Use nuts, lead, or any heavy metal that is available.


Once the weight is secured (make sure it does not shift or have the chance to fall out/off), you prime the wood. Pine soaks up paint like crazy. I put two coats of spray paint primer on my cars. Use a light color primer (white) for bright colors (bright red, yellow, white, etc and a darker primer (grey) for darker colors (like dark blue, burgandy, etc).


Make sure to let the primer cure for at least 2 hours between coats. It should be dry (not a bit tacky before moving on to painting. Paint the car as any other model and let it dry. Add any stickers/decals you want. Then add at least 2-3 coats of spray on clear coat. This makes the car shiny and protects the paint from chipping off. It also protects the stickers/decals from peeling off.


Now... after all of this is dry, you are going to put on the wheels. Before putting the wheels on (while waiting for paint to dry), you should be smoothing your tires. My recommendation is to use a medium sandpaper for the wheels at a moderate drill speed (or you melt the wheels) and then a high count sandpaper (wet) or a cloth with graphite on it.


Make sure you smooth the axels with several different roughness of sandpaper (using water with the highest/smoothest sandpaper).


Put the wheels on the car. Alignment is HUGE. You can use the thickness of three business cards to judge how much space should be between the car body and the wheels.


That is the basics. there are TONS of How-to on the web with pictures. Just search on Pinewood Derby and you will have your pick.


Good luck.

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Having my 3rd son in Cubs and having done 12 or 13 PW cars here are some quick tips.


Be sure to remove all the burrs off of the axel nails using a file. Even a cheap nail file will remove them. Look under the nail head and you will see that there is metal flashing.


Be prepared to removed weights at the weigh in. At our PW last week I saw one dad that had to tear the car apart becasue they had sealed all the weight into the car without weighing it first.


If you are not sure how muchyour car weight bring extra weights (a lot) and a fast drying super glue to the weigh in. This way you can add weights and quickly attach them just about anywhere on the car.


I try to weight the car first before painting to get as close as possible to 5 oz. I don't attach the weights but place all the parts of the car onto the scale and then add weights until I get 5 oz. Paint and glue don't really effect the weight. You can then carve out from the bottom a space for the weights. Remember you need to have enough clearance under the car for the track guide (you don't want it to scrape).


I have found the best place to put the wieghts is just in front of the rear wheels.



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Like it was said before, look online, there is a lot of suggestion there. Get a set of rules. This will be your guidance.


SAND SAND SAND. Enough said.


when you are painting, stick small adhesive dots where the axle slots are. Big enough to leave the area that your wheels will touch unpainted. this will keep the paint from causing your wheels to stick.


If this is your first derby (which it seems like it is) then go to have fun. chances are you will not win. But remember your lessons and have fun with it.


And if you do win anything, then don't rub it in on the little ones, or you may not be asked back. Always be a good sportsman.


I had a young man that ws losing to everyone, so I raced him. At the starting gate I slyly held my car back a split second, causing him to win by a long shot. He did not get a trophy, but he had a smile that was well worth the loss.

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You might hollow out a place under the car to put the weight. You need to make sure you have clearance. I also drill several small holes in the bottom. Once the car is painted and the main weight is attached you should be a little under 5oz. I then put small wood screws in the holes until I get to exactly 5oz. If you are over on the pack scale then you take out enough screws to get it right. In general, you want the center of gravity as far back on the car as you can about an inch in front of the rear axel.


Wheels. Get extra wheels. Not all wheels are the same. There is even a website out there that tells you the performance of the various molds (the mold number is inside the wheel). You can try different combinations of wheels until the car rolls straight. You can get a short test track at the Local Scout Shop, or roll it down a low incline board with a line drawn down the middle. You want the car to roll straight down the line without pulling to the right or left. This is one of the biggest factors in slowing a car down.

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Here is a website for those who are those who really want to know the ins and outs http://derbytalk.com/viewforum.php?f=11&sid=a61a9629c1320c05eb16ad112a9b710b. If you are wanting to place well, the biggest tip is polishing your axels, chuck it into a drill start with 80 grit sand paper and move up the line till 3200 grit. Lube is very important and the site can give you some help with that. Good Luck

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The final authority on legality is your race official and his scale.


A local pack here has: a by the book bracket(youth), things the book doesn't specifically address bracket(pack adults), and a C.O.P.E. rules bracket(adults-all comers).


It's amazing what some adults will do for a win :). But I'm not really telling most of you anything about that :).

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It sounds like you are going to have some fun. My troop always had a pinewood derby each year. The boys knew what they were getting for Christmas from the troop. So over Christmas break, they would work on their cars. The dads also got cars to work on as well. We would also have some dads bring in power tools like a bandsaw, beltsanders, and dremmel tools and we would have a cut night. Doing so levels the playing field for boys that do not have a dad around to help them out. Let the boys do as much as they can except using the power tools.


Just have fun with the boys.

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