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  1. #1
    Race, wreck, repeat delagem's Avatar
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    Pinewood Derby Time Again!

    Hi,

    My sons and I are building Pinewood Derby cars for Cub Scouts again. Looking for speed secrets, who's got some tips?

    Michael
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  2. #2
    gorilla03's Avatar
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    powder graphite the wheels/shaft..also try and get the weight dead center of the car..

    coming from the 1st place winner when i was in the boy scouts

    I'll post of up some pictures of my car that i won with when i was little haha

  3. #3
    bowsniper's Avatar
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    You know me, had to put my 2 cents in! GOOD LUCK!!!!!!

    If legal under your local rules, lengthen the wheelbase -- the longer wheelbases seem to be more stable.

    drill the right front axle hole higher to lift the right front wheel off the track (3 wheels, rather than 4, means a slight reduction in friction, but more importantly, it provides a place to put your worst wheel.


    What you want is wheels that run true on the axle
    and "absolutely" do not rub the car body when running. Build glue application channels for gluing in axles. This is simply drilling a 3

    Build graphite application channels for lubricating the axles and wheels. This is simply grinding or cutting away a small area of wood on the bottom of the block below the axle. It makes it much easier for the scout to apply graphite to the axles and wheels after all construction is completed.


    You will probably be adding from 1.5 - 2.3 ounces of weight. You can put weights in anywhere, but the experts say the weight placement should be biased toward the back of the car making the balance point 1" to 1 1/4" in front of the read axle.


    Building Winning Pinewood Derby Cars
    This article was written to help Dad and Scout build a reasonably fast Derby car. The steps are in order. This should make the process easier and more enjoyable. I have also tried to identify all of the steps that the scout can safely participate in. If any construction technique in this article violates your local Derby rules, do not use it. Prepare the Axle Supports (holes) in the Block
    The axle slots or holes must be square with the block. Using a drill or drill press, drill new axle holes using a #43 or #44 bit (#44 is the axle size for the new 1998 kits). We use the #43 so that the axles easily fit into the axle holes (Later you will see how we secure the axles into the holes -- all this makes it possible and easy for the scout to install and secure the axles/wheels). If legal under your local rules, lengthen the wheelbase -- the longer wheelbases seem to be more stable. I also drill the right front axle hole higher to lift the right front wheel off the track (3 wheels, rather than 4, means a slight reduction in friction, but more importantly, it provides a place to put your worst wheel. It seems there is always at least one really bad wheel in the kit).

    What you want is wheels that run true on the axle
    and "absolutely" do not rub the car body when running.
    Build glue application channels for gluing in axles. This is simply drilling a 3/32 hole or cutting a slot from the bottom of the car into the axle channel. This makes it real easy for the scout to secure the axles in with a drop or two of glue after all construction and testing have been completed. Build graphite application channels for lubricating the axles and wheels. This is simply grinding or cutting away a small area of wood on the bottom of the block below the axle. It makes it much easier for the scout to apply graphite to the axles and wheels after all construction is completed.

    Create weight storage compartment
    Pick your weights ahead of time and make a hole(s) or pit for the weight at this point. You will probably be adding from 1.5 - 2.3 ounces of weight. You can put weights in anywhere, but the experts say the weight placement should be biased toward the back of the car making the balance point 1" to 1 1/4" in front of the read axle. I totally agree with this weight placement. The images below provide what I consider to be the best idea for weight placement. The holes for the weights (3/8") are drilled to accept standard tubular weights available from your local Boy Scout supply store. This way the scout can safely participate in adding weigh to his car. A few drops of glue will hold the weights in and you can putty over the holes before painting.


    Build the car body
    This is where any age kid can get really involved and have lots of fun. Keep the car shape as simple as possible so the kids can actually help do the work. Apply the design to the block, carve (not for kids), saw, sand and paint, etc. The kids can really have fun here and, for the most part, will not negatively affect the performance of the car. Just a couple of tips here: (1) Make sure to take off a good bit off wood, because you will want to control the amount and location for added weight. (2) My fastest cars are the ones with the skinniest and slickest profile.

    Minimize rolling friction
    True and polish the wheels and axles.
    (Remember, one wheel is going to be off the track, so pick the best 3 wheels and axles to start with. You can roll the wheels on a glass table & spin the wheels and axles in a drill to find the best ones) You can really have some fun with the scouts when testing the wheels on a table. It's like a race in itself. Do not alter the basic shape of the Boy Scout kit wheels -- you only want to remove any imperfections and smooth up the finish.

    True and polish the wheels using a drill and vice setup. You clamp the drill in the vice and spin the wheels using a wheel auger (available from your Boy Scout supply store). True the wheels to round using a small flat file then polish with a 1500 grit wet-sand paper. Make sure you keep the paper wet -- this cools the work and also provides an exceptionally smooth end result.

    The axles require special treatment. A drill/dremel drill press setup is required for all steps. Using a very fine ignition file, remove the flashing from the inside head of the axle and shaft (this is where you will want to create the angle on the inside of the axle head). Polish with the 1500 grit wet-sand paper and finish off with chrome polish and a soft cotton cloth.
    Finish construction
    - Weigh all car parts and get the car to the right weight and finish off any needed sanding, painting, patching, detailing, etc. The scout can do most all of this with very little assistance. You do not want to have to do any of this type of work after the car is assembled.
    - Rub graphite on the car body where the wheel hub runs against it. Rub it in really well. Enough will stick to provide a really slick surface for the wheel to rub against if the wheel happens to hit the car body during the race. The scout can do this with minimal assistance.
    - Insert the wheels and axles into the axle holes (do NOT glue yet). We use a tongue depressor (1/16" - 3/32" thick) to set the wheel clearances. The scout can do this easily, since you prepared the special axle holes!
    Wheel clearances are critical! You want plenty
    of slack for the wheel to move freely.
    - Test the assembled car (no glue yet) on an inclined table -- glass is preferred. Test your new car against the baseline (last year's fast car). The table test will not tell you which car will be fastest on the track, but it will help you "tune" your car to be as fast as possible. The scout will really enjoy this part (as long as you don't over do it). If you have access to a track, do final testing on the track before the race. See tuning section below
    - If you have to take the wheels off for any reason. Mark the "top" of each axle and put the wheels and axles into baggies labeled LF, RF, LR, RR. This makes sure you get the wheels and axles back onto the car in the right position. You will want to have some graphite in the bags also.
    - Apply glue in the glue application channels to secure the axles. If the scout is careful, he can do this with minimal assistance.
    - Continuously force graphite into wheel and axle areas and spin them till they are worn in really well. Also rub graphite onto the wheel itself. You can't put too much graphite on -- any excess will just fall out and blow away. And, you can't spin the wheels too much -- the kids are great at spinning the wheels.
    Tuning -- Axle and wheel alignment
    A really fast derby car must have true running axles and wheels. Sometimes this happens by accident, but it is best to make sure the axles and wheels are running true by tuning the car. The scout can have some fun here but not if it's over done. Dad can do some tuning and the scout can do the kitchen table races. Some of the links below go into great detail on axle alignment, but we found these to be too detailed for either me or my son to follow. The use of wax paper shims might be o.k., but only to correct a really bad axle problem -- aligning all axles and wheels using this method is difficult and boring. I doubt you would ever find a scout that would consider this a fun exercise. Note: There are several sources for specially tuned axles and wheels -- most of these special components would be in violation of local race rules, so don't even consider it. If you and your scout can't do the work yourself, what would be the point?
    The idea is to have a car that is in near perfect alignment. Meaning that the car runs basically straight and that the wheels do not consistently ride against car body or axle head (especially against the car body!) Some of the things you can do to tune or improve the alignment are:
    - Go back to square one and make sure to start with good axle supports.
    - Make sure the better of your wheels and axles are being used.
    - In some cases switching your axles and wheels around may help.
    - If you have a wheel that insists on rubbing against the car body while rolling, use the wax paper shims to shim the axles "up" | "back" | "up and back". (See axle alignment links below).
    - If you have a really bad wheel, re-polish it and try again.
    - Continue to roll assembled car and adjust the wheels and axles until you have a car that runs true. Continue to test it against your baseline car in a mini kitchen table race.
    List of Things That Really Appear to Help - Perfect drilling of axle holes. The jury is out on angled axles -- it may very well be that this is the simplest way to produce a fast wheel/axle arrangement.
    - One front wheel off the ground.
    - The axle polish and angling of axle head using ignition file, 1500 grit wet-sand paper and chrome polish.
    - The truing and polishing of wheels using a flat file and 1500 grit wet-sand paper.
    - Sleek body profile.
    - Weight near rear of car.
    - Rubbing of graphite on the car body where the wheel hub hits the body.
    - Testing cars on inclined table making sure the car rolls true.
    - Wax paper shims to correct an out-of-line axle (if absolutely necessary).
    - Rubbing the wheels down with graphite.
    - Lots of graphite and spinning the night before the race. List of Things That Appear Not to Really Help - Glue bead (covered with graphite) on body for wheel to rub against.
    - Angled axles? (Again, not quite sure on this one). Actually this is one of the biggest boosts -- we were hoping you would not read this far. Drill the axle holes in the body at a downward angle of like 1 degree. This forces the wheels to "ride up" toward the axle head where it encounters much less friction that what it does when the wheel rubs the car body!
    - Polishing axles with graphite pencil.
    - The use of hubcaps.



    Axles holes are drilled higher on the pine wood block body
    The car is closer to the track reducing air drag by minimizing the amount of air between the car and track.

    High quality pine
    Reduces the chances of splitting or chipping.

    The car design did not play as much a role as weight, friction and alignment. Weight needs to be in the back - just think about a marble on a track - will it go faster on the incline or the flat part of the track - the incline so move the weight to the back so it is accelerating for the max time. Mount the weight across the car (not front to back) to reduce rotational force required as the car moves down the curve of the track. Do not have a pointy nose to the car or they may run it down the track backwards.

    The theoretical maximum speed of a PWD car is governed by friction and gravity. The track starts 1.2192 meters (4 feet) up and is 12.8016 meters (42 feet) long. Gravitational acceleration is 9.8 meters/sec^2 (32 ft/sec^2). A perfectly frictionless car would be going 4.89 meters/sec after falling 1.2 meters (4 feet). Going at that speed, it would take 2.62 seconds to go the length of the course. That is a car and track with no friction - not going to happen in real life. My son's car had a best time of 4 runs of 3.5004 seconds, which is 74 percent of the theoretical best speed. He beat 30 cars at the Pack and 160 cars at Districts. His car was a modified wedge - the Ground Effects Machine on this site. His car has an extended wheelbase with titanium weights in the back - high density, non-toxic. Three wheels were on the track and the axels were deburred, straightened and polished with 1500 grit emory paper and 1 mil polishing compound. Silver polish would probably do a good job for final polishing. He took the mold marks off the surface of the wheels. The only lubricant was powdered graphic. No nickel plated precision milled axels, no milled teflon covered wheels with coned hubs. Aside from the paint and the weight, everything came out of the box. Aside from the bandsaw, my son used all the tools and did all the work.

    To build a fast pine wood derby car, you need to reduce friction. Friction is the enemy of speed. Reduce friction, increase speed.
    This short tutorial gives you is a list of friction reducers that will help you make a fast, competitive pinewood derby car. It is by no means a comprehensive list of speed secrets. For more how-to information, there are several excellent sources of winning secrets listed at the bottom of this article.
    Friction DOWN, Speed UP

    Your pine wood derby car moves from the pull of gravity and is slowed down from friction. Friction acts like brakes. Reduce friction and your car goes faster. Increase friction and your car slows down. Friction DOWN, Speed UP It’s as simple as that. Finding the sources of friction and finding ways to reduce it is the tricky part. Here are some ways to reduce friction and increase speed…

    Lubrication

    How to reduce friction? An easy way to reduce friction in your pine car is to lubricate the two surfaces. This is an essential part of pine wood derby racing. Purchase a tube of graphite and sprinkle a little on the axles near the wheel. Spin the wheel so the graphite works in. You will immediately notice a significant improvement in the wheel speed as you turn it after applying graphite.
    Another good lubricant, if your rules allow it, is Nyoil II. Nyoil is a highly refined thin-film oil. Only one or two small drops on your axles reduces friction throughout your race because Nyoil stays on your axles long after graphite has dropped off in the later heats. See more details on this new lube idea in Graphite and Lubes.
    Derby Axles

    Your wheels turn on axles. One of the biggest sources of friction is where the axles and wheel surfaces meet. It is important to make your axles as smooth as possible. Be absolutely sure that the burr under the nail head is filed or sanded off. Once that is sanded off, polish the nail and underside of the head to a mirror like finish. Derby Wheels

    Imperfections in your wheels cause friction in many areas. Sanding your wheels, however, can be tricky. If the wheels are not precision sanded or lathed, you can actually make matters worse!
    Imperfections in your wheels cause friction in many areas. Sanding your wheels, however, can be tricky. If the wheels are not precision sanded or lathed, you can actually make matters worse!
    Imperfections in your wheels cause friction in many areas. Sanding your wheels, however, can be tricky. If the wheels are not precision sanded or lathed, you can actually make matters worse!
    More Weight, More Inertia, More Momentum

    Your car moves down the track from the force of gravity. If your car is too light, it will have less inertia in the flat part of the track. Be sure your car weighs as close to 5 oz as possible. Find someone with a scale, purchase an inexpensive scale or weigh your car at the Post Office. Add weights until the car with the wheels and axles is up to 5 oz. Don’t wait until race night to get this right! When I managed our pinewood derby race, there was always a scramble just before the race to weigh cars and bring them up to 5 oz.
    Making your pine wood car go straight

    This can be tricky. Roll your car along the kitchen floor. If it veers to the right or left too much, the axles are crooked. Just like steering a car, you need to adjust the steering on your Derby Car. To do this, you must adjust one or more of the axles so the car rolls straight. You can do this by re-drilling the axle holes and re-inserting the axles.
    Wheel imperfections can also make your car veer left or right. Once again, lathed wheels will remove mild imperfections so each wheel rolls perfectly straight.

  4. #4
    Canadian Beaver Inspector jkindt's Avatar
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    Biggest tip I have is to make sure your wheels are true. Spin them in a drill and true them up. And make sure your car weighs the max allowed by your rules, this may have to be adjusted at the track on race day, again biased towards the rear, it higher up on the track your center of gravity starts, the more time it has gravity pulling it rather than running on the flat part of the track. It is small but effective. Most of the winning cars in my day were thin and light at the front and had all the weight in the butt end.

  5. #5
    bowsniper's Avatar
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    Hers some ideas on styles and colors. it's endless.













































































  6. #6
    Appologizes for the last user title katz1002's Avatar
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    i won 1st place i got the trophy still ha ha i was in pack 212 i was a tiger haha i might be able to find the car i have no clue where it is right now but i drew you a similar of what i made

    to reduce friction i could machine you some wheelbearings and press fit them in the car haha i could put a zert fitting for grease capabilities and digitally design the car on a cad program to make it true haha lol you would be suprised the simpliest cars win
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  7. #7
    MODVP22's Avatar
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    Quote Originally Posted by bowsniper View Post
    You know me, had to put my 2 cents in! GOOD LUCK!!!!!!

    If legal under your local rules, lengthen the wheelbase -- the longer wheelbases seem to be more stable.

    drill the right front axle hole higher to lift the right front wheel off the track (3 wheels, rather than 4, means a slight reduction in friction, but more importantly, it provides a place to put your worst wheel.


    What you want is wheels that run true on the axle
    and "absolutely" do not rub the car body when running. Build glue application channels for gluing in axles. This is simply drilling a 3

    Build graphite application channels for lubricating the axles and wheels. This is simply grinding or cutting away a small area of wood on the bottom of the block below the axle. It makes it much easier for the scout to apply graphite to the axles and wheels after all construction is completed.


    You will probably be adding from 1.5 - 2.3 ounces of weight. You can put weights in anywhere, but the experts say the weight placement should be biased toward the back of the car making the balance point 1" to 1 1/4" in front of the read axle.


    Building Winning Pinewood Derby Cars
    This article was written to help Dad and Scout build a reasonably fast Derby car. The steps are in order. This should make the process easier and more enjoyable. I have also tried to identify all of the steps that the scout can safely participate in. If any construction technique in this article violates your local Derby rules, do not use it. Prepare the Axle Supports (holes) in the Block
    The axle slots or holes must be square with the block. Using a drill or drill press, drill new axle holes using a #43 or #44 bit (#44 is the axle size for the new 1998 kits). We use the #43 so that the axles easily fit into the axle holes (Later you will see how we secure the axles into the holes -- all this makes it possible and easy for the scout to install and secure the axles/wheels). If legal under your local rules, lengthen the wheelbase -- the longer wheelbases seem to be more stable. I also drill the right front axle hole higher to lift the right front wheel off the track (3 wheels, rather than 4, means a slight reduction in friction, but more importantly, it provides a place to put your worst wheel. It seems there is always at least one really bad wheel in the kit).

    What you want is wheels that run true on the axle
    and "absolutely" do not rub the car body when running.
    Build glue application channels for gluing in axles. This is simply drilling a 3/32 hole or cutting a slot from the bottom of the car into the axle channel. This makes it real easy for the scout to secure the axles in with a drop or two of glue after all construction and testing have been completed. Build graphite application channels for lubricating the axles and wheels. This is simply grinding or cutting away a small area of wood on the bottom of the block below the axle. It makes it much easier for the scout to apply graphite to the axles and wheels after all construction is completed.

    Create weight storage compartment
    Pick your weights ahead of time and make a hole(s) or pit for the weight at this point. You will probably be adding from 1.5 - 2.3 ounces of weight. You can put weights in anywhere, but the experts say the weight placement should be biased toward the back of the car making the balance point 1" to 1 1/4" in front of the read axle. I totally agree with this weight placement. The images below provide what I consider to be the best idea for weight placement. The holes for the weights (3/8") are drilled to accept standard tubular weights available from your local Boy Scout supply store. This way the scout can safely participate in adding weigh to his car. A few drops of glue will hold the weights in and you can putty over the holes before painting.


    Build the car body
    This is where any age kid can get really involved and have lots of fun. Keep the car shape as simple as possible so the kids can actually help do the work. Apply the design to the block, carve (not for kids), saw, sand and paint, etc. The kids can really have fun here and, for the most part, will not negatively affect the performance of the car. Just a couple of tips here: (1) Make sure to take off a good bit off wood, because you will want to control the amount and location for added weight. (2) My fastest cars are the ones with the skinniest and slickest profile.

    Minimize rolling friction
    True and polish the wheels and axles.
    (Remember, one wheel is going to be off the track, so pick the best 3 wheels and axles to start with. You can roll the wheels on a glass table & spin the wheels and axles in a drill to find the best ones) You can really have some fun with the scouts when testing the wheels on a table. It's like a race in itself. Do not alter the basic shape of the Boy Scout kit wheels -- you only want to remove any imperfections and smooth up the finish.

    True and polish the wheels using a drill and vice setup. You clamp the drill in the vice and spin the wheels using a wheel auger (available from your Boy Scout supply store). True the wheels to round using a small flat file then polish with a 1500 grit wet-sand paper. Make sure you keep the paper wet -- this cools the work and also provides an exceptionally smooth end result.

    The axles require special treatment. A drill/dremel drill press setup is required for all steps. Using a very fine ignition file, remove the flashing from the inside head of the axle and shaft (this is where you will want to create the angle on the inside of the axle head). Polish with the 1500 grit wet-sand paper and finish off with chrome polish and a soft cotton cloth.
    Finish construction
    - Weigh all car parts and get the car to the right weight and finish off any needed sanding, painting, patching, detailing, etc. The scout can do most all of this with very little assistance. You do not want to have to do any of this type of work after the car is assembled.
    - Rub graphite on the car body where the wheel hub runs against it. Rub it in really well. Enough will stick to provide a really slick surface for the wheel to rub against if the wheel happens to hit the car body during the race. The scout can do this with minimal assistance.
    - Insert the wheels and axles into the axle holes (do NOT glue yet). We use a tongue depressor (1/16" - 3/32" thick) to set the wheel clearances. The scout can do this easily, since you prepared the special axle holes!
    Wheel clearances are critical! You want plenty
    of slack for the wheel to move freely.
    - Test the assembled car (no glue yet) on an inclined table -- glass is preferred. Test your new car against the baseline (last year's fast car). The table test will not tell you which car will be fastest on the track, but it will help you "tune" your car to be as fast as possible. The scout will really enjoy this part (as long as you don't over do it). If you have access to a track, do final testing on the track before the race. See tuning section below
    - If you have to take the wheels off for any reason. Mark the "top" of each axle and put the wheels and axles into baggies labeled LF, RF, LR, RR. This makes sure you get the wheels and axles back onto the car in the right position. You will want to have some graphite in the bags also.
    - Apply glue in the glue application channels to secure the axles. If the scout is careful, he can do this with minimal assistance.
    - Continuously force graphite into wheel and axle areas and spin them till they are worn in really well. Also rub graphite onto the wheel itself. You can't put too much graphite on -- any excess will just fall out and blow away. And, you can't spin the wheels too much -- the kids are great at spinning the wheels.
    Tuning -- Axle and wheel alignment
    A really fast derby car must have true running axles and wheels. Sometimes this happens by accident, but it is best to make sure the axles and wheels are running true by tuning the car. The scout can have some fun here but not if it's over done. Dad can do some tuning and the scout can do the kitchen table races. Some of the links below go into great detail on axle alignment, but we found these to be too detailed for either me or my son to follow. The use of wax paper shims might be o.k., but only to correct a really bad axle problem -- aligning all axles and wheels using this method is difficult and boring. I doubt you would ever find a scout that would consider this a fun exercise. Note: There are several sources for specially tuned axles and wheels -- most of these special components would be in violation of local race rules, so don't even consider it. If you and your scout can't do the work yourself, what would be the point?
    The idea is to have a car that is in near perfect alignment. Meaning that the car runs basically straight and that the wheels do not consistently ride against car body or axle head (especially against the car body!) Some of the things you can do to tune or improve the alignment are:
    - Go back to square one and make sure to start with good axle supports.
    - Make sure the better of your wheels and axles are being used.
    - In some cases switching your axles and wheels around may help.
    - If you have a wheel that insists on rubbing against the car body while rolling, use the wax paper shims to shim the axles "up" | "back" | "up and back". (See axle alignment links below).
    - If you have a really bad wheel, re-polish it and try again.
    - Continue to roll assembled car and adjust the wheels and axles until you have a car that runs true. Continue to test it against your baseline car in a mini kitchen table race.
    List of Things That Really Appear to Help - Perfect drilling of axle holes. The jury is out on angled axles -- it may very well be that this is the simplest way to produce a fast wheel/axle arrangement.
    - One front wheel off the ground.
    - The axle polish and angling of axle head using ignition file, 1500 grit wet-sand paper and chrome polish.
    - The truing and polishing of wheels using a flat file and 1500 grit wet-sand paper.
    - Sleek body profile.
    - Weight near rear of car.
    - Rubbing of graphite on the car body where the wheel hub hits the body.
    - Testing cars on inclined table making sure the car rolls true.
    - Wax paper shims to correct an out-of-line axle (if absolutely necessary).
    - Rubbing the wheels down with graphite.
    - Lots of graphite and spinning the night before the race. List of Things That Appear Not to Really Help - Glue bead (covered with graphite) on body for wheel to rub against.
    - Angled axles? (Again, not quite sure on this one). Actually this is one of the biggest boosts -- we were hoping you would not read this far. Drill the axle holes in the body at a downward angle of like 1 degree. This forces the wheels to "ride up" toward the axle head where it encounters much less friction that what it does when the wheel rubs the car body!
    - Polishing axles with graphite pencil.
    - The use of hubcaps.



    Axles holes are drilled higher on the pine wood block body
    The car is closer to the track reducing air drag by minimizing the amount of air between the car and track.

    High quality pine
    Reduces the chances of splitting or chipping.

    The car design did not play as much a role as weight, friction and alignment. Weight needs to be in the back - just think about a marble on a track - will it go faster on the incline or the flat part of the track - the incline so move the weight to the back so it is accelerating for the max time. Mount the weight across the car (not front to back) to reduce rotational force required as the car moves down the curve of the track. Do not have a pointy nose to the car or they may run it down the track backwards.

    The theoretical maximum speed of a PWD car is governed by friction and gravity. The track starts 1.2192 meters (4 feet) up and is 12.8016 meters (42 feet) long. Gravitational acceleration is 9.8 meters/sec^2 (32 ft/sec^2). A perfectly frictionless car would be going 4.89 meters/sec after falling 1.2 meters (4 feet). Going at that speed, it would take 2.62 seconds to go the length of the course. That is a car and track with no friction - not going to happen in real life. My son's car had a best time of 4 runs of 3.5004 seconds, which is 74 percent of the theoretical best speed. He beat 30 cars at the Pack and 160 cars at Districts. His car was a modified wedge - the Ground Effects Machine on this site. His car has an extended wheelbase with titanium weights in the back - high density, non-toxic. Three wheels were on the track and the axels were deburred, straightened and polished with 1500 grit emory paper and 1 mil polishing compound. Silver polish would probably do a good job for final polishing. He took the mold marks off the surface of the wheels. The only lubricant was powdered graphic. No nickel plated precision milled axels, no milled teflon covered wheels with coned hubs. Aside from the paint and the weight, everything came out of the box. Aside from the bandsaw, my son used all the tools and did all the work.

    To build a fast pine wood derby car, you need to reduce friction. Friction is the enemy of speed. Reduce friction, increase speed.
    This short tutorial gives you is a list of friction reducers that will help you make a fast, competitive pinewood derby car. It is by no means a comprehensive list of speed secrets. For more how-to information, there are several excellent sources of winning secrets listed at the bottom of this article.
    Friction DOWN, Speed UP

    Your pine wood derby car moves from the pull of gravity and is slowed down from friction. Friction acts like brakes. Reduce friction and your car goes faster. Increase friction and your car slows down. Friction DOWN, Speed UP Itís as simple as that. Finding the sources of friction and finding ways to reduce it is the tricky part. Here are some ways to reduce friction and increase speedÖ

    Lubrication

    How to reduce friction? An easy way to reduce friction in your pine car is to lubricate the two surfaces. This is an essential part of pine wood derby racing. Purchase a tube of graphite and sprinkle a little on the axles near the wheel. Spin the wheel so the graphite works in. You will immediately notice a significant improvement in the wheel speed as you turn it after applying graphite.
    Another good lubricant, if your rules allow it, is Nyoil II. Nyoil is a highly refined thin-film oil. Only one or two small drops on your axles reduces friction throughout your race because Nyoil stays on your axles long after graphite has dropped off in the later heats. See more details on this new lube idea in Graphite and Lubes.
    Derby Axles

    Your wheels turn on axles. One of the biggest sources of friction is where the axles and wheel surfaces meet. It is important to make your axles as smooth as possible. Be absolutely sure that the burr under the nail head is filed or sanded off. Once that is sanded off, polish the nail and underside of the head to a mirror like finish. Derby Wheels

    Imperfections in your wheels cause friction in many areas. Sanding your wheels, however, can be tricky. If the wheels are not precision sanded or lathed, you can actually make matters worse!
    Imperfections in your wheels cause friction in many areas. Sanding your wheels, however, can be tricky. If the wheels are not precision sanded or lathed, you can actually make matters worse!
    Imperfections in your wheels cause friction in many areas. Sanding your wheels, however, can be tricky. If the wheels are not precision sanded or lathed, you can actually make matters worse!
    More Weight, More Inertia, More Momentum

    Your car moves down the track from the force of gravity. If your car is too light, it will have less inertia in the flat part of the track. Be sure your car weighs as close to 5 oz as possible. Find someone with a scale, purchase an inexpensive scale or weigh your car at the Post Office. Add weights until the car with the wheels and axles is up to 5 oz. Donít wait until race night to get this right! When I managed our pinewood derby race, there was always a scramble just before the race to weigh cars and bring them up to 5 oz.
    Making your pine wood car go straight

    This can be tricky. Roll your car along the kitchen floor. If it veers to the right or left too much, the axles are crooked. Just like steering a car, you need to adjust the steering on your Derby Car. To do this, you must adjust one or more of the axles so the car rolls straight. You can do this by re-drilling the axle holes and re-inserting the axles.
    Wheel imperfections can also make your car veer left or right. Once again, lathed wheels will remove mild imperfections so each wheel rolls perfectly straight.
    That looks just like my first 3 pinewood derby cars. Darn Pack changed the rules because of me shortly after. I always loved it. Great advice!

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