Want to take it to the next level

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BullFrog
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Want to take it to the next level

Post by BullFrog » Thu Dec 01, 2016 1:07 pm

Hey guys! First time poster!
My son has been in scouts for 2 years. Last year he took 1st in the pack and 4th in districts. He really wants to make it out of districts this year. His car was a flat car standard wheelbase. With lead weights and we bent the front axl and made it a 3 wheel rail rider. I know we left some time on the car. We could have done more work on the axels and wheels. The plan this year is the following.

Work more on the wheels. What's a good way to polish the wheel bores that won't break the bank?

We plan on doing extended wheelbase. But first I have check the rules and sew if its allowed (Northern lights district) What are the best distances to drill the holes? Also want to drill the rear holes in at a angle. We have a Axel bender but we never bent the rear axels because it looked strange.

Also going to be using tungsten for the first time. To get more of that weight were we want it. I think with these changes he might be able to take it to the next level.



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Re: Want to take it to the next level

Post by Speedster » Thu Dec 01, 2016 3:38 pm

Hello BullFrog, Welcome to Derbytalk.
You obviously are not an absolute beginner at this. This is what I would do. Learn to use the "search" function on Derbytalk. Buy the book, "Build a Winning Pinewood Derby Car" by Troy Thorne. You can get it from Fox Chapel Publishing and some Michaels Stores carry it. If we knew all your exact rules it would make it easier to answer any question you might have.

Here's something I have learned over the past 31 years that I have been involved in the Cub Scout Pinewood Derby. Some scouts are very difficult to beat. Our District Race uses a 35' Best track. The cars race 29'10" from pin to timer. The elapsed time is published for every race and I have records of the times of the fastest cars. I have in my garage a 2 lane, 35' Best track. with the same MicroWizard timer that records time at the District track. I know about how fast my scouts car has to go on my track to be competitive at District. Our Dominant front wheel is always set with Positive Camber. The very slightest adjustment on the DFW will affect the elapsed time, either for better or worse. That gives my scouts a tremendous advantage and we have lots of Fun in the summer months building cars.

The Physics of the Pinewood Derby is fascinating. Check your rules carefully. Search, Search, Search Derbytalk for information.
This site is loaded with info from many brilliant racers. Above all, have Fun with your son. Sure, trophies are Fun to get and the thrill lasts a little while but the memories your son will have remembering the time spent with you will last forever.
Best,
Speedster



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Re: Want to take it to the next level

Post by whodathunkit » Thu Dec 01, 2016 6:39 pm

Hi and :welcome: BullFrog

You asked what's a good way to polish bores that wont break the bank.
( I'll leave that up to you and your son for your needs in your quest for more speed.)

Here are some thoughts about wheel bore prep that are often over looked that can break the bank.. and a set of wheels right off the bat.

I think there are a lot of builders here on DT that will tell you that this step is often over looked.
And more wheel bores are trashed because of this step that was missed.
It's best to wash your wheels in warm soapy water and dry them good before starting wheel prep.

Getting a good looking glass to see whats going on inside with the wheel bores helps.

Some will use Q-tip shafts & some fluffy pipe cleaners to polish the bores with. ( some problems some in counter with these items .)
Q-tips shafts swelling up and binding up in the bore or pipe cleaners with the wire centers scratching the wheel bore.
Some builders on here say they use the TAMIYA brand cotton swab spears in there wheel bore prep.
And some say to use a dab of hot melt glue on the pipe cleaner wire ends.. to help keep the wire end off the wheel bore side wall as a Tip.
Some Polishes: for wheel bore prep are . tooth paste, liquid glass, or even Novus polish #2 & #3, or bore wax by derby worx and so on.
Tip's for tools used for burnish in graphite.. smooth rod to fit the wheel bore.. round end of #41 drill bit, pine car brand solid axle, or pin gauges.


Best tip I can offer in your car building is don't over think things to much and get off track.
Good Luck this year and go get em' guys.
Whoda.


What type of automobile can be spelled the same forwards & backwards?

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BullFrog
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Re: Want to take it to the next level

Post by BullFrog » Thu Dec 01, 2016 7:51 pm

Thanks for the tips. Tooth paste to polish wheel bores!? I have never heard that before. I will look into that one for sure



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Re: Want to take it to the next level

Post by Vitamin K » Thu Dec 01, 2016 8:57 pm

BullFrog wrote:Hey guys! First time poster!
My son has been in scouts for 2 years. Last year he took 1st in the pack and 4th in districts. He really wants to make it out of districts this year. His car was a flat car standard wheelbase. With lead weights and we bent the front axl and made it a 3 wheel rail rider. I know we left some time on the car. We could have done more work on the axels and wheels. The plan this year is the following.

Work more on the wheels. What's a good way to polish the wheel bores that won't break the bank?

We plan on doing extended wheelbase. But first I have check the rules and sew if its allowed (Northern lights district) What are the best distances to drill the holes? Also want to drill the rear holes in at a angle. We have a Axel bender but we never bent the rear axels because it looked strange.

Also going to be using tungsten for the first time. To get more of that weight were we want it. I think with these changes he might be able to take it to the next level.
Here's what I'd recommend:

First, I think Whoda is spot-on with the bore prep recommendations. The only caveat I'd throw in is that the Derby Worx bore wax is actually a post-polishing coat that you'd apply, rather than a polishing compound. My kids and I use Novus 2 on bores, with fluffy pipe cleaners. If we have the time, we'll first polish with Pepsodent Whitening toothpaste, then do the final polish with the Novus (washing thoroughly with Blue Dawn dish soap between each polishing).

If you're going to build a rail-rider (which I recommend), one of the key elements is getting your rear alignment dead-on. Since you seem to want to go with drilled camber, make sure that you have proper tooling to do so. There are some DIY suggestions from people like Sporty here. Other folks like to use a drill press and a tool like The Block to hold the car in the proper place. There are also a lot of hand-drill jigs on the market now that have gotten very positive reviews...though they are on the spendy side (100-150 bucks).

Just as important as getting a good drill setup, though, is testing the alignment of the rear axles after the drill. Search for Lightninboy's alignment tests and make sure that the car passes them before moving on.

Also, I would strongly suggest that you build a tuning board for setting/testing the car's drift. It's nearly impossible to have a good rail rider without a tuning board on which to test it.

Regarding wheelbase, I find that about 5 inches is a good compromise between stability and potential energy transfer. If you have an older track, however, you may want to go full extended for maximum stability.

Best of luck to you and your son!



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Re: Want to take it to the next level

Post by BullFrog » Thu Dec 01, 2016 9:33 pm

Vitamin K wrote:
BullFrog wrote:Hey guys! First time poster!
My son has been in scouts for 2 years. Last year he took 1st in the pack and 4th in districts. He really wants to make it out of districts this year. His car was a flat car standard wheelbase. With lead weights and we bent the front axl and made it a 3 wheel rail rider. I know we left some time on the car. We could have done more work on the axels and wheels. The plan this year is the following.

Work more on the wheels. What's a good way to polish the wheel bores that won't break the bank?

We plan on doing extended wheelbase. But first I have check the rules and sew if its allowed (Northern lights district) What are the best distances to drill the holes? Also want to drill the rear holes in at a angle. We have a Axel bender but we never bent the rear axels because it looked strange.

Also going to be using tungsten for the first time. To get more of that weight were we want it. I think with these changes he might be able to take it to the next level.
Here's what I'd recommend:

First, I think Whoda is spot-on with the bore prep recommendations. The only caveat I'd throw in is that the Derby Worx bore wax is actually a post-polishing coat that you'd apply, rather than a polishing compound. My kids and I use Novus 2 on bores, with fluffy pipe cleaners. If we have the time, we'll first polish with Pepsodent Whitening toothpaste, then do the final polish with the Novus (washing thoroughly with Blue Dawn dish soap between each polishing).

If you're going to build a rail-rider (which I recommend), one of the key elements is getting your rear alignment dead-on. Since you seem to want to go with drilled camber, make sure that you have proper tooling to do so. There are some DIY suggestions from people like Sporty here. Other folks like to use a drill press and a tool like The Block to hold the car in the proper place. There are also a lot of hand-drill jigs on the market now that have gotten very positive reviews...though they are on the spendy side (100-150 bucks).

Just as important as getting a good drill setup, though, is testing the alignment of the rear axles after the drill. Search for Lightninboy's alignment tests and make sure that the car passes them before moving on.

Also, I would strongly suggest that you build a tuning board for setting/testing the car's drift. It's nearly impossible to have a good rail rider without a tuning board on which to test it.

Regarding wheelbase, I find that about 5 inches is a good compromise between stability and potential energy transfer. If you have an older track, however, you may want to go full extended for maximum stability.

Best of luck to you and your son!
So much great info :bigups:
Is this the stuff you are referring to?
Image

We just take a board and put it at incline and see how much the car drifts to one side. I think last year we were about 3 inches.

We have a pretty nice track we race on. So maybe 5 inch wheelbase. Is the only reason to do the extended base is for stability?



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Re: Want to take it to the next level

Post by Vitamin K » Fri Dec 02, 2016 8:44 am

BullFrog wrote: Is this the stuff you are referring to?
Image
That's the stuff!
Bullfrog wrote: We just take a board and put it at incline and see how much the car drifts to one side. I think last year we were about 3 inches.
That's probably good enough. I also like attaching a guide strip to the other side of the tuning board so I can watch the behavior of the wheels as the car rolls along the strip. If the rears aren't staying off of the rails, you know something has to be corrected!
Bullfrog wrote: We have a pretty nice track we race on. So maybe 5 inch wheelbase. Is the only reason to do the extended base is for stability?
My understanding of wheelbase theory is that the shorter wheelbase gives you better energy transfer out of the transition, while the longer wheelbase gives the car a more stable ride. Too short and you'll be overly sensitive to track inconsistencies and possibly be more prone to the "wiggle of death". The 4 3/8 standard wheelbase, IMO, is a little bit too sensitive. 5 inches is a nice sweet spot between fully extended and stock.



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Re: Want to take it to the next level

Post by Speedster » Fri Dec 02, 2016 3:35 pm

BullFrog, I'd like to share my technique that I've had success with for many years. I use the cotton swab shaft and Novus 2. I then coat the bores with Liquid Glass. Novus 2 is specifically designed to remove scratches in plastic and polish. I do not use Novus 1 or Novus 3.
OK, here we go. Q-tip is a brand name for a cotton swab and is to big to use for bores. They generally measure 0.101 which is too big for the bore. The cotton swab you need is sold by Walgreen's and reads "studio35beauty". They are double-tipped cushioned COTTON SWABS. They generally measure 0.099 which works well on the bore. I stick about an inch of the shaft out of the drill, coat it with Novus 2, coat the bore with Novus 2, and run the drill slowly to 1/2 speed, working the shaft back and forth in the bore. You should hear a bit of squealing. After you use the swab for a short period of time the paper gets wet and will become smaller and I feel it is no longer polishing and removing scratches, if there are any scratches. It will leave a beautiful shine. I then clean the bore with an extra fluffy pipe cleaner in a drill while holding the wheel under running water. The Liquid Glass is a polish and I use it because others suggested it and I feel it can't hurt. I hope it helps a bit. The wheels are then lubed with Hob-E-Lube graphite since we are only allowed to use graphite. We have never been allowed to use oil so I know nothing about oil.
If you stick the swab way out of the drill it is very difficult to get the swab started because it wants to bend before it enters the bore. If you have difficulty finding the proper cotton swab, email me with your mailing address and I'll send you some. I have a new box of 500 since we use them at our workshops and we have a workshop coming up.



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Re: Want to take it to the next level

Post by BullFrog » Fri Dec 02, 2016 5:26 pm

Speedster wrote:BullFrog, I'd like to share my technique that I've had success with for many years. I use the cotton swab shaft and Novus 2. I then coat the bores with Liquid Glass. Novus 2 is specifically designed to remove scratches in plastic and polish. I do not use Novus 1 or Novus 3.
OK, here we go. Q-tip is a brand name for a cotton swab and is to big to use for bores. They generally measure 0.101 which is too big for the bore. The cotton swab you need is sold by Walgreen's and reads "studio35beauty". They are double-tipped cushioned COTTON SWABS. They generally measure 0.099 which works well on the bore. I stick about an inch of the shaft out of the drill, coat it with Novus 2, coat the bore with Novus 2, and run the drill slowly to 1/2 speed, working the shaft back and forth in the bore. You should hear a bit of squealing. After you use the swab for a short period of time the paper gets wet and will become smaller and I feel it is no longer polishing and removing scratches, if there are any scratches. It will leave a beautiful shine. I then clean the bore with an extra fluffy pipe cleaner in a drill while holding the wheel under running water. The Liquid Glass is a polish and I use it because others suggested it and I feel it can't hurt. I hope it helps a bit. The wheels are then lubed with Hob-E-Lube graphite since we are only allowed to use graphite. We have never been allowed to use oil so I know nothing about oil.
If you stick the swab way out of the drill it is very difficult to get the swab started because it wants to bend before it enters the bore. If you have difficulty finding the proper cotton swab, email me with your mailing address and I'll send you some. I have a new box of 500 since we use them at our workshops and we have a workshop coming up.

Wow thank you for the detailed info :dance: We will check out Walgreen's this weekend. We can use oil. But I think we will stick with graphite



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Want to take it to the next level

Post by whodathunkit » Fri Dec 02, 2016 8:21 pm

Good Info VK & Speedster!

BullFrog,
A word of caution that i'll pass on is this ..
I don't know if Speedster forgot to say something about shaft sizes of the studio 35 swabs running wild for sizes in the box:
he may or may not be experiencing this with his stock.
Some of the older walgreens 625 swab shafts ran wild for sizes 0.099 up to 0.104 back when you could get them before the change over to studio 35 swabs
at Walgreens.

Now I can't talk for Speedster on this but watch out and check the shaft sizes:
As you may think there all the same in size when they may or may not be .

Some Tip's I'll pass on to check the shaft sizes:
Image

For a quick way to check size's and then maybe re size the shafts is to use a decimal equivalents number size dill gage machine screw tap & wire gage.
You know how you can resize wooden dowel rods with them.. same might go for shaving down the paper shafts if there to large and your in a pinch not to waste them. However use your best shafts in the same size that haven't been shave down..( paper will be smoother!)
Last edited by whodathunkit on Fri Dec 02, 2016 8:21 pm, edited 1 time in total.


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Re: Want to take it to the next level

Post by Vitamin K » Sat Dec 03, 2016 5:36 am

Lots of really fast racers swear by Studio 35 Q-tip stalks, so I don't think you can go wrong there. Definitely agree with Whoda on checking the thickness. Also, I'd also recommend that you and your son practice polishing on some throwaway wheels first, since it's not terribly hard to destroy a bore with q-tip stems if you spin too quickly.

Regarding oil: If I'm ever allowed to use oil, I will do it every time. Oil really is Pinewood Lubrication 2.0 and there's no comparison from graphite in terms of performance or longevity. If the other fast racers in your Pack and District are going to be running oil, they're going to have a definite advantage from it. If you are interested, I can detail the basic technique I employ for it.



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Re: Want to take it to the next level

Post by Speedster » Sat Dec 03, 2016 6:36 am

I've never had a problem with the shaft size yet but I do check each one with calipers before using it. You never know what might happen.



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Re: Want to take it to the next level

Post by BullFrog » Sat Dec 03, 2016 11:58 am

Vitamin K wrote: My understanding of wheelbase theory is that the shorter wheelbase gives you better energy transfer out of the transition, while the longer wheelbase gives the car a more stable ride. Too short and you'll be overly sensitive to track inconsistencies and possibly be more prone to the "wiggle of death". The 4 3/8 standard wheelbase, IMO, is a little bit too sensitive. 5 inches is a nice sweet spot between fully extended and stock.
Going over the rules from last year. Looks like there is only a minimum wheelbase requirement. :eager: The front wheels just can't stick out beyond the front of the car
Image



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Re: Want to take it to the next level

Post by Vitamin K » Sat Dec 03, 2016 2:40 pm

BullFrog wrote: Going over the rules from last year. Looks like there is only a minimum wheelbase requirement. :eager: The front wheels just can't stick out beyond the front of the car
Image
The Northern Star rules are, in my opinion, among the best rules ever drafted for Cub Racing.

That said, there are some seriously fast racers in that Council, and the rules will let you build an extremely competitive car.

I know that Lightninboy and Davet have had success within the NSC. Definitely search out some of their posts and read up! And, again, you really should consider learning and running oil. Once you experience the difference, you'll not want to bother with graphite anymore. :)



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Re: Want to take it to the next level

Post by Speedster » Sat Dec 03, 2016 4:20 pm

If you check the MidAmerica finals for 2016 between Scout Graphite and Scout Oil you will find Oil is consistently faster than Graphite. If I have the 1st place times correct it is Oil-2.9112 and Graphite 3.0698. Graphite never beat oil in the first 6 fastest cars. I don't doubt you can mess up with oil but there are super experts on Derby Talk that can detail the particular oil and how to apply it. NOPE. I'm not one of those racers that can help you. I will now be quiet.
Best
speedster



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