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Post by derbygal on Mar 31, 2009 15:45:40 GMT -6
As far as I know our district uses the standard box version of the rules which is fairly vague about axels.
Are they allowed to be moved back or lengthen the wheelbase??
We have the "Official Grand Prix Pinewood Derby Kit" No. 17006 Is there a newer version out there this year and maybe these are last year's rules??? I don't read anything about having to keep the axels where they are on the block.
Thanks for your thoughts.
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Post by the woodbutcher on Mar 31, 2009 16:27:28 GMT -6
That would be a question for your Scoutmaster to answer. It would seem, however, that the Pack rules are a little more liberal than the district's/ finals. I was asking the same questions after reading the rules (ours) sent me. I ended up calling him ask asking. I, too, wanted to lengthen the wheelbase and use holes in place of the axle slots. He kind of acted like I had to use the block as is, and couldn't lengthen it. As it turned out, during the check in the cars were weighed - but hardly looked at otherwise. Lot's of cars had a longer wheelbase ! Some things you can do to 'use the original slots' are : * Orient the block so the longer end of the block is in the front. This will move more of your weight to the rear. * If you do the above, you could also cut a piece from the rear of the block and glue it back on the front. This will move the rear wheels as far back as possible. Be careful not to remove too much and leave your wheels hanging off the back. * Drill your axle holes in the top of the slot. This keeps it looking like the original slots with the benefit of well aligned holes for the axles. Most people use the pro body tool for this.
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khouse
Head in the Pine
Posts: 199
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Post by khouse on Mar 31, 2009 18:35:38 GMT -6
Post your rules and let us figure them out.
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Post by derbygal on Mar 31, 2009 21:04:14 GMT -6
Thank you for your thoughts on these rules... I have another question: is it allowable for a car to be removed during a race if it's not damaged b/c they say it doesn't follow the rules below??? Seems to me that would be a bigger violation than the axles not being in the standard slots... Thank you for your help. Ok, here are the rules in our box: IMPORTANT: The Race Committee should decide on rules and race procedures, then have them printed and distributed to all participants at least two weeks before the race. CAR SPECIFICATIONS: Width - 2 3/4", Length - 7", Weight - Not over 5 Ounces, Width between wheels - 1 3/4", Bottom clearance between car and track - 3/8" RULES Wheel bearings, washers and bushings are prohibited. The car shall not ride on springs. Only official Cub Scout Grand Prix Pinewood Derby wheels and axles are permitted. Only dry lubricant is permitted. Details, such as steering wheels and driver are permissible as long as these details do not exceed the maximum length, width and weight specifications. The car must be free-wheeling, with no starting devices. Each car must pass inspection by the official inspection committee before it may compete. If, at registration, a car does not pass inspection, the owner will be informed of the reason for failure, and will be given time within the official weigh-in time period to make the adjustment. After final approval, cars will not be reinspected unless the car is damaged in handling or in a race. Building Instructions Check groves to ensure that each is at a perfect 90-degree angle to the car body. A car with untrue axles tends to steer to one side or the other, causing it to rub up against the side of the lane strip, slowing it down. You can check the groove angles by using a square, a protractor, or even a piece of paper. Lay square on block to check for squareness and alignment of slot. Use two hacksaw blades side by side to redress the slots. Use the edge of the square as a guide. Choose your favorite design, then mark the block accordingly (see figure 1 - which shows a 90 degree angle behind the front axle). Lay car body on the side, then gently drive the axles into the grooves within 1/4" of the axle head. Axles should fit tight. With a pair of pliers, remove axles by pulling and turning gradually. Repeat on the other side of the block. Most of the cutting can be done with a handsaw, then finished with sandpaper. Details such as fins and scoops should be added now. Any additional weight needed to acheive 5 oz should be built into the car. NOTE: If the car design you choose has a narrow body, make sure the area where the axles are inserted into the body remains 1 3/4" wide or wheels will not fit over the guide strips of the track. Then there are painting instructions...
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Post by derbygal on Mar 31, 2009 21:09:52 GMT -6
Oh, I guess maybe the painting instructions COULD be considered a rule??? We assumed the Building Instructions and Painting and Wheel assembly were not rules since they were not in the rules section... is this a correct assumption??? I'm confused. Thank you. PAINTING AND WHEEL ASSEMBLY Apply several coats of sanding sealer; then sand entire car with a fine-grade sandpaper. Give model at least two coats of fast-drying paint in your choice of color. When paint is completely dry, sand with a fine sandpaper, apply a final coat of paint and allow to dry thoroughly. TO FINISH, rub entire car with a rubbing compound. Details such as a steering wheel, windshield, driver, racing numbers, etc should be added now. For a super finish apply a coat of auto wax and rub to a high gloss. Pre-lubricate axles and wheels using dry powdered lubricant. Do not use regular oil or silicone spray, since it may soften the plastic. Slide wheels over axles, then gently tap them into the car body grooves with a 1/4" dowel or similar object to within 1/32" of car body. Make sure wheels turn freely.
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Post by gpraceman on Apr 1, 2009 8:21:07 GMT -6
IMO it is rather unreal that a district race would be using the "rules in the box" and not publish a set of their own rules (like the Important notice states). Those are really vauge and can be interpreted differently. As far as I know, those "rules" were published back in 1997 and have not been updated since. A lot has changed in the derby world since then.
If you have any questions on the rules, you should contact the race coordinator and get clarification (preferably in writing).
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Post by the woodbutcher on Apr 1, 2009 10:21:43 GMT -6
Something to remember is : a poorly prepared car will always finished 2nd to a well prepared car, no matter what the wheelbase is. My advise to you is call the Scoutmaster (or whoever is running the race) and ask. I was presented with the same situation and after talking to him, I went with the std wheelbase, moved back. I showed up at the race, and counted half a dozen cars or more, all with a long wheelbase I only lost 1 race - in the final - (you guessed it) to another well prepared car with a std. wheelbase. Hey, you could build 2 cars ....
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Post by derbygal on Apr 1, 2009 11:51:12 GMT -6
Well, I guess our pack follows the rules on the box, but the district follows their own rules which do NOT allow wheels to be moved. Interesting. I did get a copy of the district rules and they are two pages long. I am a little overwhelmed by this! They are letting my son go to districts to race since his times were right up there with the top finishers - as long as i can get the wheels fixed... but that would throw off the whole weights and such. I need to do some more reading on this. I guess a new car is in order and lots more reading... wish i would have discovered this website BEFORE his last car was built.
These rules say that the wheels may not be altered in any way. This means that you can't put graphite on the outsides of them? Hmmm... But it's good everyone will be racing by the same rules! That is good. :-)
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Post by gpraceman on Apr 1, 2009 12:00:29 GMT -6
Your pack should really adopt the district rules, like them or not. Otherwise, they can easily put their district qualifiers at a competitive disadvantage. After being involved in 4 district races, running two of them, numerous times people would give me the line "but it was allowed to run in our pack race". That may have been the case, but we were enforcing the district rules, not their pack's rules.
Are you sure they don't allow at least a light sanding to remove the mold mark?
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Sappington R
Head in the Pine
"The Sappster" 10oz
Posts: 210
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Post by Sappington R on Apr 1, 2009 18:38:32 GMT -6
Derbygal, Welcome to the forum and congratulations on your son's success to date.
After reading this thread I couldn't help but to throw in my .02
It is very, VERY unusual that any district or pack in 2009 would prohibit ANY wheel mod's including sanding, polishing, and removing the molding mark.
In addition to the comments made earlier by Butcher, gpraceman, and K-house (inventor of the K-groove) I would suggest speaking with a parent or leader that has participated in that particular district race in the past to get the heart of the matter.
It is good that you have found this community and if you persist, you may just help your son(s) and others take the prize.
Regards,
Sapp.
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khouse
Head in the Pine
Posts: 199
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Post by khouse on Apr 1, 2009 22:38:43 GMT -6
The way I read it I see a modified car. It says to only "check" the axle grooves. Not "use" the grooves. It says to use the specified wheels. But it doesn't say you can't modify them. It says to use the specified axles. But it doesn't say you can't modify them. It looks to me the rules are wide open.
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Post by derbygal on Apr 2, 2009 17:20:54 GMT -6
Here's our Rules for district: Very excited and a little overwhelmed about this. We can't move the axles and must use the slots provided, however, that doesn't mean we can't cut the car and position it how we want, right??? I read this on here as well as filling in the slots with some sort of filler and redrilling those holes perfectly straight and tight. Seriously, does aerodynamics really matter??? I've seen some websites that say it doesn't make a bit of difference. Is this true? We did well in our pack but I know we're up against big-time guys now and really want to do help him as much as I can... who doesn't, right? Here's the rules: Any tips that you think we can work within these rules will be HUGELY appreciated! And this lube stuff they talk about is it better than graphite? THE CAR 1. The car must be newly built for the current cubscouting year. The car should be substantially build by the scout. Parental supervision in the construction of the car is encouraged. 2. The body of th car must be made from the block of wood provided in an official BSA PD Kit. Loose pieces that fall off during a race are not permitted. If the front of the car is designed to gain an unfair advantage at the start or interferes with a fair start, the car will be disqualified. 3. the axles of the car must be from the official BSA PD Kit or an official PD wheel replacement kit. Axles must be firmly attached to the car. The use of flexible suspension system of any type is prohibited. 4. The wheels of the car must be from the official BSA PD kit or an official PD replacement kit. Wheels may not be altered in anyway. Mold projection defects on wheel treads may be removed by sanding lightly. The wheels may not be sanded to enhance performance. The decorated dots on the wheel treads may not be removed. If wheel sanding is detected the car will be disqualified. The wheels must be attached to the car with the axles provided in the kit. No cars will be accepted in the District PD where bearings, washers or spacers are used as part of the wheel assembly. The official wheel width is 0.34". The wheels must be placed in the slots provided. if a slot is broken a new car body is needed. Wheels may not be designed to ride upon the guide strip of the track. 5. Lubrication - only graphite powder or the new BSA white lube T102/polytertra fluoroethylene may be used to lubricate wheels. The District PD will NOT provide graphite powder lubricants. Once the car is impounded, it may NOT be re-lubricated. 6. The total weight of the car may not exceed 5 oz. The max width of the car, including wheels, may not exceed 2.75". The max length of the car may not exceed 7 inches. The motion of the car may not be mechanically aided (motor, springs, rubber bands, etc are prohibited) 7. The District PD Committee may disqualify a car that in their determination is not in compliance with the spirit of the PD Race.
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khouse
Head in the Pine
Posts: 199
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Post by khouse on Apr 2, 2009 17:53:58 GMT -6
It doesn't say that you cant: 1. Cut and glue the body 2. Modify or buy BSA modified axles 3. Just use 3 wheels 4. Shave your wheels to the decorative dots. 5. Polish the wheel bores 6. Cant your rear axles. I have done it with the slots. Just put some super glue on the axles. 7. Bend any axle to tune your steering. Or you can bend the rear axles too. Looks to me like you can build a fast car.
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Post by gpraceman on Apr 2, 2009 18:49:03 GMT -6
I read this on here as well as filling in the slots with some sort of filler and redrilling those holes perfectly straight and tight. The rules don't seem to preclude that. However, I would make sure that the tips of the axles are left exposed, so it is obvious that nails are used for axles, not machined pins. Seriously, does aerodynamics really matter??? I've seen some websites that say it doesn't make a bit of difference. Is this true? To eek out the most out of a car, yes it does. However, you get far more impact from good COG location, wheel and axle prep, wheel alignment, and proper lubrication. Aerodynamics is much less of a concern, but from the get go you might want to encourage your son to select a sleeker design (minimal frontal area). With that out of the way, concentrate on the other items I listed. 4. The wheels of the car must be from the official BSA PD kit or an official PD replacement kit. Wheels may not be altered in anyway. Mold projection defects on wheel treads may be removed by sanding lightly. The wheels may not be sanded to enhance performance. The decorated dots on the wheel treads may not be removed. If wheel sanding is detected the car will be disqualified. The wheels must be attached to the car with the axles provided in the kit. No cars will be accepted in the District PD where bearings, washers or spacers are used as part of the wheel assembly. The official wheel width is 0.34". The wheels must be placed in the slots provided. if a slot is broken a new car body is needed. Wheels may not be designed to ride upon the guide strip of the track. This rule rather contradicts itself! "Mold projection defects on wheel treads may be removed by sanding lightly." - This is reasonable and should be allowed. "wheels may not be sanded to enhance performance." - Seems to contradict the first statement. You remove the mold mark to make the wheel perform better. "If wheel sanding is detected the car will be disqualified." - So, you can lightly sand, but it must not be detectable? 5. Lubrication - only graphite powder or the new BSA white lube T102/polytertra fluoroethylene may be used to lubricate wheels. The District PD will NOT provide graphite powder lubricants. Once the car is impounded, it may NOT be re-lubricated. Stick to graphite. Many people report that the white lube is worse than no lube at all. 7. The District PD Committee may disqualify a car that in their determination is not in compliance with the spirit of the PD Race. This last rule seems to be a land mine! Seems they can suspect something fishy and based only on that suspicion, disqualify the car. That has a huge potential to be abused.
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Sappington R
Head in the Pine
"The Sappster" 10oz
Posts: 210
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Post by Sappington R on Apr 2, 2009 18:56:36 GMT -6
Khouse, Good suggestions, however a three-wheeler may freak them out at check-in. But agree, is within rules posted.
Derbygal, I think the wheel modification issue is a non-issue after reading your latest post. You could get a wheel mandrel and sand them down. A Derbyworx Wheel Shaver XT would also be acceptable. In addition, MaxV has a very nice magnetic wheel balancer-
I also believe that you would be within the rules if you purchased basic lathed (non-lightened) matched wheels- all of the internet retailers can help you- Derbydoc, MaxV, Derbydominator, Pinewoodextreme- to name a few. I can assure you that other district racers will by purchasing "done" wheels.
Hope this helps.
Sapp.
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Post by gpraceman on Apr 2, 2009 19:04:33 GMT -6
I also believe that you would be within the rules if you purchased basic lathed (non-lightened) matched wheels- all of the internet retailers can help you- Derbydoc, MaxV, Derbydominator, Pinewoodextreme- to name a few. I can assure you that other district racers will by purchasing "done" wheels. I'd be a bit hesitant to recommend any aftermarket parts, based on their last rule. If the Committe knows or suspects that a part is aftermarket, can that be deemed to be "not in compliance with the spirit of the PD Race"? Aftermarket parts can be seen as taking shortcuts to the building process and may also be deemed as an unfair advantage to those that can't afford spending money on those parts. It all boils down to how the committee interprets that last rule.
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Post by derbygal on Apr 2, 2009 19:17:10 GMT -6
Awesome! I'm sorry to say that I do have to buy the wheels... we don't have much time to build a new car. We bought wheels last time and they had a silver coating on them but I'm thinking that probably isn't allowed and don't want to risk it. Sounds to me that I can go hog-wild on the axles though and get what graphite coated axles as long as they're BSA??
I think it's a great idea to leave the ends of the axles exposed to prove they're real axles... although then they'd see they're graphite coated... but it didn't give any specs on the axles really, right? And we can cut the slots deeper before filling with epoxy so the car rides lower? Gosh, this is so confusing to me.
So thinner is better... I'll have to suggest some thin designs. But how do you put weight in such a thin design??? We had a little man last time and it was good. If we cut some of the car off, what is preferrable? cut the short end off and glue in front? Sorry, I'm just pressed for time now with the district race in two weeks and we've never been before and I know the competition will be scary!!!! YIKES.
What is Canting wheels or is it axles? Thank you for all your replies, it's REALLY helpful. This is an awesome site!!!!
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Post by derbygal on Apr 2, 2009 19:24:43 GMT -6
I also believe that you would be within the rules if you purchased basic lathed (non-lightened) matched wheels- all of the internet retailers can help you- Derbydoc, MaxV, Derbydominator, Pinewoodextreme- to name a few. I can assure you that other district racers will by purchasing "done" wheels. I'd be a bit hesitant to recommend any aftermarket parts, based on their last rule. If the Committe knows or suspects that a part is aftermarket, can that be deemed to be "not in compliance with the spirit of the PD Race"? Aftermarket parts can be seen as taking shortcuts to the building process and may also be deemed as an unfair advantage to those that can't afford spending money on those parts. It all boils down to how the committee interprets that last rule. Hmmm... you make an excellent point.... certainly not the graphite coated wheels since that would be altering the wheels but I think the removing all those mold marks has to be done somehow and I don't know how.
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Post by the woodbutcher on Apr 6, 2009 19:44:26 GMT -6
It doesn't say that you cant: 1. Cut and glue the body 2. Modify or buy BSA modified axles 3. Just use 3 wheels 4. Shave your wheels to the decorative dots. 5. Polish the wheel bores 6. Cant your rear axles. I have done it with the slots. Just put some super glue on the axles. 7. Bend any axle to tune your steering. Or you can bend the rear axles too. Looks to me like you can build a fast car. I agree with Khouse. These rules may seem restrictive, but that's only on the surface. There's a lot of room to build a fast car. Remember : everyone else has to follow the same rules and be inspected by the same committee.
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Post by speedgt on Dec 5, 2009 9:41:05 GMT -6
i need help.....my car is already finished and find i could use .100 oz of wieght, i have flat tungston weight at the very bottom end of rear of car, should i put 3/16 cube and tungston putty weight on top of existing weight which will be 1/2 inch above bottom of car and at the very end or put same weight in front of existing flat 1/2 inch wide tungston but at the bottom of car,so question is higher at very end or at very bottom and just in f/o rear axel. the COM is 1-1/8" in f/o rear axel and weight is 121.5 oz in front and 368.5 oz in rear. since the car is finished (painted,decal,and polyyurethane) i would rather put weight under car (less body damage) but i don't want to sacrifice speed. my grandson and I thank you, SPEED GT
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