First time racer tiger cub. Week to go just looking for some speed help.

[Newtoderby]

HI group.

My boy is in the tiger scouts so this is his first derby. Of course he wants to win. So I have been reading and reading and a lot of it on here and I finally decided to post and ask for some help. We are actually making three cars. Our pack runs a sibling and a parent race as well. We have been having fun getting them ready. Our younger boy who is 4 is happy that it looks like a boat and he has pirate stickers. My car I am trying to make fast /images/boards/smilies/smile.gif Got a challenge from my fellow tiger leaders that to see who would have the fastest car. So I want to at least be competitive. and finally our tiger guy who is 6. picked his design we made it added on a lego guy head and helmet tucked in like a race car driver and just the head. Of course he saw a picture of a car with guns on it so we had to add two small rods that are I think he said lasers /images/boards/smilies/smile.gif. Ok stats

Tigers car is 4.9 ounces pre stickers he has to have some stickers(so he tells me) Its his car so his call. I have most of the weight in front of the rear axle. Cog in the inch in front of rear axel range. Rules for us call for regular bsa wheels and axels you must have 4 wheels on the car but you no rule on how many touch track. dry lube only. must make the car no pre made kits. Wheels can not be sanded other then to remove any deformity on the outside ie a form mark etc. basically no crowning wheels or sanding them they will dq or make you change wheels if they have been sanded to change tread. I have polished the axels filed smooth then 220, 400, 600, 2000, polish and then 0000 steel wool with buffing compound. they are very shiny. tried to match wheels but best we could do out of three kits is match front set both #6 and rear both #7

My car 4.98 ounces(this makes me nervous I don't know how good my scale is compared to the official scale but we will have time to adjust that night.) All the cars I used lead I can drill out and put tape over it if need be. Everything else the same. as above

4year olds 4.98 ounces also weight in this one I just put a lead bar in a carved out groove. no idea where center of gravity is not too concerned.

Ok so cars are all painted and I am now just about up to putting wheels on the cars. The inside of the wheels all I have done is put graphite inside chuck on the drill press and hold the wheel against it while it spins add some more graphite and repeat. I did this only to the four year olds so far. qtips I have seem fat and I don't have plastic polish compound. So anything I should do here? DO I pledge the axels then graphite is that ok with dry lube only?? In regards to putting the wheels on I seem to get the impression that three wheels touching is better but then I get lost on wheel cant or bending. In regards to drilling the axels I don't have the guide and no time to buy one and not really in the budget. So what do I do with axels and four wheels on ? lift one of the fronts? bend the axels? which ones and which way. I got to say I am kinda confused on the axel parts. The slots on all the cars I made sure are square and I also read many times do not hammer in the axels. Also I read a 1/32 inch gap is correct I can do that with a feeler guage. I am also concerned that with all the weight in the back in front of the rear will the car be too rear heavy and fly up in the front>??? I did put a tiny amount in the front because of the fly up concern)

Ok I am going to stop rambling know. I think I have derby fever. I also think I have read way too much and am now having too many debates about proper setup and what to do. So with a week left any advice about how to finish off the cars so he has a good chance of at least placing. The one boy has won several times and took districts last year He is aware of the speed tips and his folks have been happy to help with tips cause they would like to see some competition. So I am trying to give some and of course have fun along the way.

Thanks you guys have a great forum

 

[Rocket car]

Welcome to the the forum! When you look at the back of the car the wheels should look like this. / and the front view should look like this | or this | /.

 

[GravityX]

Welcome to the NPWDRL!

Here is a great thread on prepping with Pledge.

 

[Obsessedderbydad]

Might be too late to cant the rears now. Dont worry about the weight. You actually want the majority of the weight as far back as possible. The higher the weight is on the track the more PE or Potential Energy. It will feel rear heavy, but that's ok, you're car isnt going to flip. Most cars run a COG from .5"-.75". Shinny axles are good. Wheel prep, burnish the wheel bore. http://www.pinewoodderbyonline.com/post/burnishing-6801483?pid=1281940338#post1281940338 <-- Recent talks on burnishing. Yes apply pledge to the axles, let dry or just wipe it off. Either way you're wiping it off and the axle wont be wet so you're not breaking the rules. 3 wheels are better than 4. If you can just drill or cut into 1 side more than the other for your raised wheel. If you want a matched set you can buy matched sets for like $5. Thin to win. Here's a good start for everything you'll need to know to win scout races.
http://www.pinewoodderbyonline.com/post/keys-to-win-from-the-pinewood-derby-king-5782181?pid=1272943640#post1272943640
and/or
http://5kidsracing.webs.com/

 

[IAE Racing]

Welcome. /images/boards/smilies/wave.gif

No wheelies with a 1 inch com. To raise one front wheel, simply use a coping saw and saw a little deeper on one side. this will raise. Only bend one axle if you choose to. this will be the front wheel touching (DFW). Take a spare axle or one the will be use on a lifted front, grip it with pliers or locking pliers and wiggle this axle into where you want the axle hole to be(relaxing the axle hole). If you chose to bend an axle, then you will need to read up on tuning. It's ok to just run all three axles straight. If you chose to cant the rears, you can relieve the rear slots at an angle like Rockets pic.

Keep reading. 5Kids website. Ask specific questions. Use Search function.

 

[OPARENNEN]

[QUOTE
I have most of the weight in front of the rear axle. NO! as much weight behind axle as possible.

Cog in the inch in front of rear axle range. Rules for us call for regular BSA wheels and axles you must have 4 wheels on the car but you no rule on how many touch track. Always raise one front wheel. Other front wheel needs to be bent slightly,so you can turn it back and forth to adjust steer. Adjust steer so car drifts to the opposite side of dominant wheel by about 4 to 5 inches over four feet. E.g use a table with one side raised so car slowly goes down.

dry lube only. Use a mixture from DD4H that has graphite and Mag. must make the car no pre made kits. Wheels can not be sanded other then to remove any deformity on the outside ie a form mark etc. basically no crowning wheels or sanding them they will dq or make you change wheels if they have been sanded to change tread. I have polished the axels filed smooth then 220, 400, 600, 2000, polish and then 0000 steel wool with buffing compound. they are very shiny. tried to match wheels but best we could do out of three kits is match front set both #6 and rear both #7 You should have sanded also with 3000, 8000 and 12000 grit. Thereafter, polish with 3M synthetic car wax (or better, DD4H Axle Polish). Afterwards, spray axles with Jig-a-loo, if you can find it.

4year olds 4.98 ounces also weight in this one I just put a lead bar in a carved out groove. no idea where center of gravity is not too concerned.

Ok so cars are all painted and I am now just about up to putting wheels on the cars. The inside of the wheels all I have done is put graphite inside chuck on the drill press and hold the wheel against it while it spins add some more graphite and repeat. I did this only to the four year olds so far. qtips I have seem fat and I don't have plastic polish compound. So anything I should do here? Rub graphite on body by axle holes. DO I pledge the axels then graphite is that ok with dry lube only?? I don't use pledge, other do. In regards to putting the wheels on I seem to get the impression that three wheels touching is better YES but then I get lost on wheel cant or bending. Rear wheels absolutely parallel to the track, bottoms canted out, uper wheels canted in. I.e. Insert axles in body slots at a slight angle. In regards to drilling the axels I don't have the guide and no time to buy one and not really in the budget. So what do I do with axels and four wheels on ? lift one of the fronts? bend the axels? CAREFULLY ON DOMINANT FRONT. Put tiny slot in head to you can adjust it with a small screwdriver. which ones and which way. I got to say I am kinda confused on the axel parts. The slots on all the cars I made sure are square and I also read many times do not hammer in the axels. Also I read a 1/32 inch gap is correct I can do that with a feeler guage. I am also concerned that with all the weight in the back in front of the rear will the car be too rear heavy and fly up in the front>???(btw tiger and mine I drilled holes in the bottom and poured lead into them and then filled with wood putty and sanded smooth.) I did put a tiny amount in the front because of the fly up concern) With a COG of 3/4 to one inch, fly up is no concern. I run with COG 1/2 inch in front of rear axle. (unless track is home made with a very sudden transition point)

[/QUOTE]

 

[DEW36]

Welcome to the forum!!

 

[Newtoderby]

Wow,

Thanks for all the fast replies.

Ok so here is my plan based on replies above and reading.

1. burnish the wheels with the graphite.
2. I will raise one front wheel by cutting groove a little deeper on that side.
3. I am going to run the axels straight. I don't think I have time to figure out all the canting and adjusting. Also bending seems like it may cause problems this late in the game.
specific questions:

1. I assume to check straightness If I put a piece of tape on the kitchen table say whole length and push the car down it I should be able to see if it stays straight. ie doesn't move into tape left or right. if it does I assume turn the axels to fix till it runs straight?

2. I have also read do not glue the axels in place? is that correct? and then do I put tape over the slot ie scotch tape?

Thank you all for the help

 

[Crash Enburn]

Welcome!

Just to be clear, it is possible to put too much weight in back. As long as your CoG is 1/2" or more in front of the rear wheels you'll be fine.

Since you have no way of buying DD4H's graphite before your race, go with Hob-E-Lube graphite (available at Hobby Lobby). Do not use the white teflon (?) powder -- it's pretty well useless.

Do not be afraid of using a LOT of graphite. Seriously. Burnish it into the bores. Burnish it into the Pledge on the axle (Pledge is just a spray wax. It dries after a couple minutes, and you polish it off. No worry about any rule breaking.) Put the axle into the wheel, add graphite and spin the wheel. Add graphite, and spin the wheel. Ad infinitum.

Before trying to mount the wheels to the body, do what IAE suggested, and use a spare axle (or one that will be used for the raised front wheel [which, by the way, does not require polishing or burnishing of the hub]) to relax the holes/slots where the axles will go. Push it in, pull it out. Repeat until you can pull the axle back out without veins on your forehead standing out.

The axle for your Dominant Front Wheel (DFW) is the only one that gets bent. Just a couple degrees of bend. The 1 minute mark on your clock, by the way, is 6 degrees. So, bend to 30 sec or less. This bent axle will let you change the angle of the front wheel (for steering) by turning the axle. You want that wheel to turn the car to the opposite side. Again, you're shooting for a turn of approx. 4" after rolling 4 feet.

The rear axles get installed at an angle of 3 degrees, so the rear of the car looks like this /-[]- from behind. Do your very best to get the angle matching, and the rear wheels absolutely parallel with one another. Otherwise, they're pulling/pushing against one another and scrubbing speed. (Not to worry though, at this point, you are already way ahead of the game)

Once the wheels are on, my sons and I have spent the idle hours in the nights before the race holding the car upside-down, adding a bit of graphite to the wheels, and spinning them. (Upside down because then the section of the hubs that are getting super-burnished are the same parts that will be contacting the wheel hubs during the race.

Right before check-in, one more puff of graphite into the bores, and you're done.

PS- Don't let the boys play with the cars until after the race. Or, if the car is qualified for the District race, no playing then, either. /images/boards/smilies/smile.gif

 

[txchemist]

Also, see if you can bust up your weights so that IF the scale at check in calls you over, you can fix it without messing up your car. I had a very strange thing happen at Districts- I know my car was 4.98 oz. from two good calibrated scales. The scale at districts had us at 4.5 oz, and they had piles of zinc weights for anyone to add to the car, and many were doing so. Our car had many empty holes drilled into the bottom and covered with metal tape. It was simple to open up the next possible location close to the back axle and add three nickels to bring up the weight. I promise everyone, that moving the COG a tiny bit forward was more that made up with added speed from increasing the weight. If the scale had been 1/2 oz. too heavy, we make our best cars with 12 cubes of tungsten behind the axle, and 6 nickles just on the other side, three per hole typically, and plenty of empty holes. Bring extra tape in your pit tools kit. Also an extra wheel and axle, all prepped. I always make that adult car axles and wheels 100% able to meet the Cub rules so any and all can be substituted if needed. Once we needed all 4 when the car got launched off the start into the air and onto the floor. The start gate had a serious bounce back if you flipped it hard and let go.

 

[IAE Racing]

If you're using your table, prop up one end slightly so the car will roll on its own. Even if you are not bending or canting, if your cars move or turn toward the lifted front wheel, that's okay as long as it does not move more than 4" in 4'. Ideally your rear axle will be straight and parallel though. You don't want your back axles steering.

It would be ok to put a small drop of CA at you axle tips, but most likely will not be needed. I have seen glued axles be either a curse or blessing.

 

[Newtoderby]

You guys are great lots of great information and even though I have been reading a lot this has helped focus a lot of it in. Will be working on the wheels this weekend and attaching them to the car.

I will keep you all posted and will let everyone know how it comes out.

Thank you Thank you Thank you

 

[Newtoderby]

Update,

Ok Wheels are on all three cars. The youngest for the sibling race we just put all four wheels into the slots and was done with it. I am tuning to try and get it to track straight which is a challenge but in the grand scheme of things he is happy its blue and has pirate stickers. That is what it really is about /images/boards/smilies/smile.gif. Now onto my car and the Tigers. Both cars I raised a front wheel. On the tigers the one axel had a slight bend in it anyway so I left it put the rears in straight at least best I could with massaging in the one axel ahead of time. It currently is turning towards the wheel that is up in the air which is on the left(if you were looking from behind ie the drivers side on a real car). I followed the 5kid diagram on the tracking and measured it out on a 5 foot desk and at 4 feet it consistently is between 3.5 and 4 inches at the 4 foot mark. Just making sure I got this right he basically will end up riding the rail this way and I think I have it correct. Again it is turning towards the wheel on the left which is the wheel in the air. Just like it is taking a slow left hand turn. My car I bent the axel in the front tried to angle the rears the same I am running about 5 inches at 4 feet towards the up wheel as well. All the wheels I have at a gap between wheel and car under 1/32" I used a .022 feeler guage for it nothing is rubbing. I did burnish the wheel bores inside with graphite and the boys and I are adding and graphite and spinning at least daily. Not that we are excited or anything for Friday /images/boards/smilies/smile.gif

The tuning cellar is in full swing and hope is running high. Just I hope I am helping give my kiddo the best chance without goofing it up /images/boards/smilies/smile.gif At the end he is having fun and that is the best.

 

[HMH Racing]

I think this may be too late, but did you shave a 1/16" from the right front, wheel area (DFW)? You can also notch it.

Reducing the front width of the car keeps the rear wheels from riding the rail. You only want the front to touch.