Car set up question about RR and maybe more.

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miko
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Car set up question about RR and maybe more.

Post by miko »

I have some questions and not sure if I should put them all here or in some cases post in a 3 year old thread I read.

Well I will post a few questions here now.

Some backgroung.. I think we use a best track.. not sure lenght but the horizontal part looked longer then the hill/

On a RR car.. I looked to see if anyone posted if anything should be on the inside wheel lip of the dom front wheel that will be touching the center rail. I have seen threads debating if graphite should be on tread.. and I guess that conclusion was no but I am also curious about the part that will slide down the center rail. We only have rule against what to use on the axle.

8. Wheel bearings, washers, pads, and bushings are prohibited. Wheels must bear against wood or
painted wood.

13. No oil, grease, lubricant, non-stick, or lubricating coatings, other than dry graphite or dry white
Teflon, shall be used on axles. No additional applications will be allowed after check in. Please do
so over a trash can if applying at check in.

14. No wheelbase modifications and no extended wheelbases will be allowed. The stock axle slot
dimensions must be used. The distance between the axles and the distance from the front of
the car to the first axle must be maintained.



On the width of the car for RR.... I saw a thread debating weather to sand off 1/32 or 1/16 or 3/32 inch off the front...probably the DFW side. I thought some had said if sand too much off the car will bind?



On the alignment or cam of axles... I have not seen this idea in the forums but I'm sorry if it is... but has anyone used tiny screws with a dome head? I worry bout the axel moving in the axel slot. But, if I put a small screw in the front axle slot toward the the middle where the tip is so that part of the axle is higher then where the axle leaves the side of the car. The the opposute on back slot ...putting the small domed screw by the edge of the car forcing that part of the axel higher then the tip.

This is getting long so I think I will put my graphite and com questions in a different thread.

Thanks
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sporty
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Re: Car set up question about RR and maybe more.

Post by sporty »

Id rather take a phone call from you. I think you are looking for some very indepth replies and I am a horrible typer.

Sporty

Pm, me.
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Stan Pope
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Re: Car set up question about RR and maybe more.

Post by Stan Pope »

These questions really belong more in the "Car & Semi-Truck Construction" section of the forum.

Narrowing the front of the car is a short-cut that simplifies drilling axle holes that yield the design camber and toe angles for the various axles. Rears axles can be perpendicular to the direction of travel and still have the wheels off the rail when the DFW is touching the rail. The smaller the indentation of the DFW, the more precision that is required of the rears.

There is just a bit more than 1/8" to play with ... wheels plus gaps plus stock body width is about that much larger than the rail width.

1/16" inset for DFW is a good compromise.

The problem for using screws as an alignment technique is the strength of the wood that the threads leverage from. That wood gives way before the axle orientation can be altered to the desired amount. A small "set screw" (1/8" X 1/8" is about the smallest I've seen) could still be used to help lock the axle in position, but the possibility that tightening it will slightly alter the alignment makes it less desirable than glue.

An insert made of, for instance, steel can provide strength, but probably creates a larger cross section than you want.
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Re: Car set up question about RR and maybe more.

Post by miko »

Sorry for putting in wrong area.

One question I had that didn't get a comment yet. Should I lube the inside wheel lip that will ride the rail? Im thinking I should but what should I use? Since the only rule I see is on what is put on the axle..i want the slickest lube on the RR wheel lip.

Stan.. I wasn't wanting to use the screw so it locks in the axle but so the screw is under the axle preventing the axle from being level.

By putting the screw, say 1 inch towards the middle of the front axle slot it would raise the axle tip on the front wheels making them ride the inside of the wheel. Then in the rear only going 1/8 from the edge of the car so the axle tip is lower.. putting the rear wheels on the outside edge of their tread.
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Re: Car set up question about RR and maybe more.

Post by miko »

Looking at the images in this thread (page 8) maybe i just said that backwards and i need the front wheels with the axle tip pointing down.

http://www.derbytalk.com/viewtopic.php? ... &start=105" target="_blank
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Re: Car set up question about RR and maybe more.

Post by FatSebastian »

miko wrote:Since the only rule I see is on what is put on the axle.
Note that by mentioning "axle", the rule may actually intend that lubricant only be applied around the axle and nowhere else, rather than allowing a different kind of lube away from the axle. :/
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Re: Car set up question about RR and maybe more.

Post by Stan Pope »

miko wrote: Sorry for putting in wrong area.
You will not be executed at dawn for that, but don't be surprised if a moderator moves the threads!
miko wrote:One question I had that didn't get a comment yet. Should I lube the inside wheel lip that will ride the rail? Im thinking I should but what should I use? Since the only rule I see is on what is put on the axle..i want the slickest lube on the RR wheel lip.
A think coating of graphite on the lip, with no loose graphite, will almost certainly not be noticed.
miko wrote:Stan.. I wasn't wanting to use the screw so it locks in the axle but so the screw is under the axle preventing the axle from being level.

By putting the screw, say 1 inch towards the middle of the front axle slot it would raise the axle tip on the front wheels making them ride the inside of the wheel. Then in the rear only going 1/8 from the edge of the car so the axle tip is lower.. putting the rear wheels on the outside edge of their tread.
Moving the axle with a screw in wood will fail because too much force is required. Holding an axle in the path you have provided may work. I would not use a screw with a head. A head would either stick out or would prevent the screw from engaging deeply enough. Counter-sinking loses too much strength.
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Re: Car set up question about RR and maybe more.

Post by miko »

FatSebastian wrote:
miko wrote:Since the only rule I see is on what is put on the axle.
Note that by mentioning "axle", the rule may actually intend that lubricant only be applied around the axle and nowhere else, rather than allowing a different kind of lube away from the axle. :/
At the last den mtg.. one of the dads asked if ok to cheat ( which I'm sure was a joke) prompting another dad to say.. he was using nascar rules..if the rules don't say you can't do it.. it must be legal. The den leader said thats fine as long as they don't break any of the rules. So I don't think its a problem since its not on the rules.

Mybe I should post all the rules
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Re: Car set up question about RR and maybe more.

Post by miko »

miko wrote:One question I had that didn't get a comment yet. Should I lube the inside wheel lip that will ride the rail? Im thinking I should but what should I use? Since the only rule I see is on what is put on the axle..i want the slickest lube on the RR wheel lip.
A think coating of graphite on the lip, with no loose graphite, will almost certainly not be noticed.
miko wrote:Stan.. I wasn't wanting to use the screw so it locks in the axle but so the screw is under the axle preventing the axle from being level.

By putting the screw, say 1 inch towards the middle of the front axle slot it would raise the axle tip on the front wheels making them ride the inside of the wheel. Then in the rear only going 1/8 from the edge of the car so the axle tip is lower.. putting the rear wheels on the outside edge of their tread.
Moving the axle with a screw in wood will fail because too much force is required. Holding an axle in the path you have provided may work. I would not use a screw with a head. A head would either stick out or would prevent the screw from engaging deeply enough. Counter-sinking loses too much strength.[/quote]

Since I think lube on the wheel thats not on the axle is ok... would other lube be better.. say pam cooking spray or dry and buffed car wax?

I just don't think we are on the same page with my screw idea.. I might see if I can take a pic or 2 of what i am meaning
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Re: Car set up question about RR and maybe more.

Post by miko »

I guess read if board.

1. The width of the car shall not exceed 2-3/4 inches. The length of the car shall not exceed 7
inches. Check in template will govern clearance requirements.

2. The weight of the car shall not exceed 5 ounces or 142 grams as measured at check in with
official scale. It is recommended that car be as close to 5 ounces as possible for best performance.

3. The original amount of bottom clearance of 3/8 inch must be maintained. Check in template will
govern clearance requirements. No weights or materials that decrease this clearance will be
allowed.

4. The Leading edge of car must not extend past starting gate.

5. The axles, wheels, and body wood shall be as provided in the official BSA Pinewood Derby Kit. One axle may be pulled on each car to verify that the axles have not been modified.

6. Diameter, width, and profile of wheels shall not be altered from their original form as provided in the kit. Original “as molded” surface finish must be clearly present. You may remove the mold
parting line seam from the wheels.

7. All four wheels must touch the track. Check in template will govern.

8. Wheel bearings, washers, pads, and bushings are prohibited. Wheels must bear against wood or
painted wood.

9. The car shall not ride on any springs.

10. Details added must not exceed width, length, weight requirements and must be secured to car with glue or fasteners.

11. The car must be freewheeling with no starting devices.

12. No loose materials of any kind are allowed in or on car.

13. No oil, grease, lubricant, non-stick, or lubricating coatings, other than dry graphite or dry white
Teflon, shall be used on axles. No additional applications will be allowed after check in. Please do
so over a trash can if applying at check in.

14. No wheelbase modifications and no extended wheelbases will be allowed. The stock axle slot
dimensions must be used. The distance between the axles and the distance from the front of
the car to the first axle must be maintained.

15. Car numbers will be issued on stickers at check in and affixed to the top of car. It is OK to put
numbers on top and sides but issued number will be used for scoring.

16. Race officials will hold all cars passing inspection until competition is concluded.

17. Race officials will put the cars on the starting line, start the race and retrieve the cars.

18. Repairs after check in will be allowed for wheels and axles only. Detail parts such as drivers,
steering wheels, fenders… will not.

19. Should the electronic scoring system fail, repairs will be attempted to correct the problem and the race will be rerun. In the event of a complete electronic scoring system failure, the official judges will decide winners of each heat.

20. If a car leaves the track, runs out of its lane, interferes with another car, loses an axle, etc., the heat will be rerun. If the same car gets into trouble on the rerun, the car will be disqualified and that heat will be rerun without the disqualified car.

If a car fails to meet any of the above rules it will be automatically entered in a Modified Class. Cars in this group will compete in the races but will be limited to finishing no higher than eighth place.
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Re: Car set up question about RR and maybe more.

Post by Stan Pope »

miko wrote: ...
Since I think lube on the wheel thats not on the axle is ok... would other lube be better.. say pam cooking spray or dry and buffed car wax?

I just don't think we are on the same page with my screw idea.. I might see if I can take a pic or 2 of what i am meaning
I'd be cautious of other lubes unless you have time to test them. Graphite in that app is proven.

On use of screw: I understand that you would run the screw vertically up the slot toward the axle, inboard for DFW, outboard for rears. What is not coming across is what you hope to gain from it.
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Re: Car set up question about RR and maybe more.

Post by FatSebastian »

:offtopic:
miko wrote:5. The axles, wheels, and body wood shall be as provided in the official BSA Pinewood Derby Kit. One axle may be pulled on each car to verify that the axles have not been modified.
:scratching: It is unclear what "as provided" means. It seems to suggest that the axles cannot be reworked / improved at all; however, the "body wood shall be as provided" would imply that everyone would be racing 7" x 1.75" x 1.25" blocks of wood, which can't be correct.
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Re: Car set up question about RR and maybe more.

Post by miko »

FatSebastian wrote::offtopic:
miko wrote:5. The axles, wheels, and body wood shall be as provided in the official BSA Pinewood Derby Kit. One axle may be pulled on each car to verify that the axles have not been modified.
:scratching: It is unclear what "as provided" means. It seems to suggest that the axles cannot be reworked / improved at all; however, the "body wood shall be as provided" would imply that everyone would be racing 7" x 1.75" x 1.25" blocks of wood, which can't be correct.
That just means we have to use the axles that were in the box. We went to a lowes workshop last year... and they talked about removing the burres on the axle head.. i didn't think we could do any of that.

So I called one of the pack or district leaders and he adv we can remove that and do some light sanding but we cannot sand so much we create a indention in the axle..He said that would be modifing it.

I Think that just about everyone had the same diminsions last year.. I took a pic of the cars before the kids voted on their favorite I'll see if I can post it.
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Re: Car set up question about RR and maybe more.

Post by miko »

Image

let see if this works
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Re: Car set up question about RR and maybe more.

Post by miko »

well i don't see pic.. so here is link to album i just made.


http://s1144.photobucket.com/albums/o487/miko1207/" target="_blank
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