Son of a Pickle

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jacksdad
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Son of a Pickle

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My 10 year old son's pack just ran their PWD race today and he won for the second year in a row, placing first in all of his races. He did a lot more on this car - the "Son of a Pickle" - than previous years, from the design to the build. He shaped it with the bench grinder, Dremel, files and sandpaper, and while I did some of the more difficult curves and details for him, he did much of the bodywork including spraying the two tone green paint job himself. He's regularly on DT researching the latest speed tips, and the car was built pretty much how he wanted it - extended wheelbase, three wheel rail rider with 2.5 degree negative camber on the rear wheels, 2.5 degree positive camber on the right DFW, 1/16" indented front, and 3/4" COG with a tungsten disc in back. He polished the axles with a Derby Monkey kit (400, 600, 1000, 1200, 1500, 2000, 2500, 4000, 6000, 8000 grit paper/polishing cloth and sub micron polish), and wet sanded each color coat before spraying the next, resulting in a beautiful shine when we hit it with wax. The body is 1/4" thick at the front and 1/2" at the back, and he wanted to cut the body away around the wheels to prevent the rims hitting and slowing it down. It all seemed to work as he was consistently at least 0.050 seconds ahead of the second place car, and each race was won by at least a length, and sometimes as much as five. The aggressive COG was really apparent at the transition from the incline to the straight, as the videos show it really extending it's lead from that point. He was a great winner, and several times I saw him congratulate the runners up, and telling them it was a "good race". It's his last year before he crosses over, so he wanted to "go for it" at the Districts. Fingers crossed and thanks for all the great advice :bigups:
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Last edited by jacksdad on Tue Apr 17, 2012 11:37 pm, edited 1 time in total.
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Re: Son of a Pickle

Post by Speedster »

CONGRATULATIONS to your son and you. That is a beautiful car. Good Luck at Districts.

Would you tell us what you did to the wheels? Were they purchased? If so, which ones did you purchase? If graphite was used, which graphite? How were the wheels prepared with the lubricant? Were the bores reamed?
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sporty
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Re: Son of a Pickle

Post by sporty »

Nice looking car, congrats !

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Re: Son of a Pickle

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Sporty - thank you :)
Speedster - we're limited to what we can do to the wheels (no lightening, thinning, machining, etc) so we prepped the wheels by truing them up with a Derby Work XT wheel shaver from the Scout store. It was a bear to get used to, but as soon as I learned that the blade as delivered is too blunt and needs to be sharpened regularly (after gouging chunks out of more than a dozen wheels) it did a much better job. I found the key was to work on small arcs of the tread at a time, holding the wheel still and rotating the tool back and forth over a small portion of the high spot. Also, the spring on the adjustment screw tends to wind the blade back out after you let go, and oftentimes you have to bring it in too far to compensate for the spring backtracking and you have another gouge. Turning the adjustment knob AND the spring at the same time (grip them together as you turn and make sure you feel the spring rotate in relation to the tool's body) and you can make much finer adjustments. The wheels are USA made and we didn't mold match them - I put them in the wheel shaver and checked the run out by bringing the blade within a hair of the tread and slowly turning them. Any that looked like they were more than 10-15 thou out of round were discarded as I found I couldn't get them trued up and stay within the limit of 1.175". Incidentally, for those who are mold matching wheels, the good numbers seem only to apply to the US made ones, not the Chinese Revell wheels. While they have very tight bores, the Chinese wheel's run out is horrific. We ended up with three complete sets of Chinese made #3 wheels (a good mold according to all the speed secret books) and couldn't use any of them. The good mold numbers apparently only apply to the domestic wheels, which are cheaper at the Scout store anyway. A good reason to buy the US made product.
After I shaved them and checked that they were round and still legal (I took off the bare minimum and kept them at 1.180" to be on the safe side), we trued up the inner edge of the tread with the wheel shaver and chucked them up in a mandrel. Spinning them on the lowest speed on my Dremel, we cleaned them up with 1000 wet and dry and lots of soapy water. Incidentally, all three of the mandrels we tried were bent, and we had to straighten the best of the them to get it to work. Check your mandrel if you're using it to true up your wheels with sandpaper as it may well be bent. Without the wheel shaver, that was the method we used last year, and when we rechecked our wheels it was shocking to see how bad they were.
The bores were polished with the Pro bore polisher and the supplied polish. I couldn't figure out how to use the supplied tool without risking the metal coming into contact with the bore. Running short of time we chucked up short sections of the pipe cleaner that came with it in the drill press and ran each wheel on a fresh piece with polish for about 10 seconds on the slowest speed. I wish we'd had more time to use Sporty's method, but we didn't unfortunately. The same polish was also used on the wheel treads, inner hub, out hub and inner tread edge as it's water based and doesn't have potentially damaging petroleum distillates.
We lubed the axles/wheels with Hob-E-Lube and broke them in with the Dremel on the slowest speed and a soft polishing wheel for about 5 minutes, reapplying every minute or so. We switched to Derby Monkey's graphite for the last few minutes for no good reason other than I had a tube laying around. I still have it under my fingernails :/
One thing we did that I'm sure played a huge role was meticulous wheel alignment. My poor kid was pulling his hair out while we checked and rechecked our measurements before committing to drilling the first hole. I wanted to leave the axle holes until last so any warping would already have taken place, and the car was so thin that I couldn't guarantee sitting it on edge would put it straight on the drill press, so we bought a piece of 2"x2" poplar and found the corner that was exactly 90 degrees. Taping the bottom of the car to an 8" piece, we were able to get the axles exactly where we wanted them, and absolutely true to each other. It took almost three hours to work out the exact axle placement (wheelbase, height from the base to compensate for the positive and negative cant on the axles from front to rear, and square to the centerline taking into account the front wheel indent) and drill them, but with me holding the car/poplar block on the table, and my son running the drill press, we ended up with the truest block we've ever had.
Long post, but I hope it helps.
Last edited by jacksdad on Wed Apr 18, 2012 12:01 am, edited 2 times in total.
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Re: Son of a Pickle

Post by Noskills »

Really cool car. I see te alignment time paid off. Congrats.
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jacksdad
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Re: Son of a Pickle

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Thank you Seth. It turned out great, and it was such a positive learning experience for my son. My Dad taught me so much, and this was my chance to pass it on. I realized early on that he was committed to going the extra mile to make this one his best car yet, so I took pictures at each step in case anyone thought it was all me. He was a perfectionist when it came to polishing the axles, and his paint job amazed me as he sprayed all the coats himself without a single run and they all came out like glass. I had him sand between coats with 1200 wet and dry and soapy water though, and that was tough for him to understand because he thought it looked great anyway, but on race day I heard him telling some of the other kids that the reason the wood grain wasn't showing through on his car was because he'd wet sanded it.
To his credit, he was committed to doing everything legally and he was adamant that he didn't want to use any aftermarket parts, so between us we modified the BSA wheels, axles and block ourselves. The wheels were shaved with the Derby Worx tool from the Scout store just enough to remove the high spots, and he wanted to use the BSA axles even though we had some Revell ones that looked much better out of the box. About the only thing we didn't buy from the Scout store (other than paint supplies) was the tungsten weight and the axle polishing kit, although I almost cleaned them out of wheels a couple of times while I was learning to use the tool :oops:
I have to give a shout out to the Scouts and adults who gave up their time to put together yet another great Derby. As always, it was impeccably organized and very well run and the Cub Scouts had a great time :bigups: :bigups:

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http://i1224.photobucket.com/albums/ee3 ... Dremel.jpg" target="_blank
http://i1224.photobucket.com/albums/ee3 ... anding.jpg" target="_blank
http://i1224.photobucket.com/albums/ee3 ... raying.jpg" target="_blank
http://i1224.photobucket.com/albums/ee3 ... anding.jpg" target="_blank
http://i1224.photobucket.com/albums/ee3 ... dTSOAP.jpg" target="_blank
http://i1224.photobucket.com/albums/ee3 ... on2012.jpg" target="_blank
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Noskills
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Re: Son of a Pickle

Post by Noskills »

Are those pin stripes painted or tape. They are nice. Also how did you get the tungsten disc in so snug?
Seth
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Re: Son of a Pickle

Post by whodathunkit »

:o Now thats one BIG Vise your useing if i've ever seen one.. Jacksdad.
And a very slick looking car also.. I like how he wet sanded the paint!
Looks smooth as glass and Fast also.
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What type of automobile can be spelled the same forwards & backwards?
jacksdad
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Re: Son of a Pickle

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Seth - they're tape. We went with silver at first, but before we even put them on, my son said he wanted to go with red as he said it would "make it pop". We used the Dremel to carve a hole in the back for the weight, and then epoxied it in place and filled the gap around the edge with JB weld. The body was sanded down to the level of the weight so it sat flush. A quick run to the Post Office had shown it was coming up a little light (we went with a 3.0oz disc), so before it was glued in place we added some tungsten putty in the bottom of the hole. It also has three open holes drilled in the bottom that are filled with putty so we can adjust the weight on race day.
Whoda - thank you. With the awesome cars I've seen you turn out, praise from you is praise indeed. He hated the wet sanding, especially as I was a little cautious with it being his first time and limited him to 1200 grit and soapy water, but it was definitely worth the effort. And I love my Harbor Freight vise - it's proved indestructible so far.

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Re: Son of a Pickle

Post by whodathunkit »

jacksdad wrote: Whoda - thank you. With the awesome cars I've seen you turn out, praise from you is praise indeed. He hated the wet sanding, especially as I was a little cautious with it being his first time and limited him to 1200 grit and soapy water, but it was definitely worth the effort. And I love my Harbor Freight vise - it's proved indestructible so far.
Thank you Jacksdad,
But the praise needs to go to your son for all the hard work he put in wet sanding his car.
And when it comes right down to the kids cars vs the ones I make.
I always like theres better then mine. ;)

Mark.
What type of automobile can be spelled the same forwards & backwards?
jacksdad
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Re: Son of a Pickle

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First in District and third in Council :)
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Re: Son of a Pickle

Post by whodathunkit »

jacksdad wrote:First in District and third in Council :)
Congrats.. ;) :bigups: :bigups: :bigups:
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jacksdad
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Re: Son of a Pickle

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Thanks Mark :D
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Re: Son of a Pickle

Post by whodathunkit »

jacksdad wrote:Sporty - thank you :)
Speedster - we're limited to what we can do to the wheels (no lightening, thinning, machining, etc) so we prepped the wheels by truing them up with a Derby Work XT wheel shaver from the Scout store. It was a bear to get used to, but as soon as I learned that the blade as delivered is too blunt and needs to be sharpened regularly (after gouging chunks out of more than a dozen wheels) it did a much better job. I found the key was to work on small arcs of the tread at a time, holding the wheel still and rotating the tool back and forth over a small portion of the high spot. Also, the spring on the adjustment screw tends to wind the blade back out after you let go, and oftentimes you have to bring it in too far to compensate for the spring backtracking and you have another gouge. Turning the adjustment knob AND the spring at the same time (grip them together as you turn and make sure you feel the spring rotate in relation to the tool's body) and you can make much finer adjustments.
Jacksdad,

For the blade take it out of the tool.
The tapered side of the blade is the trailing end.. Run it over a honeing stone with oil or WD-40
at a 15 dreg angle.
By starting on the far end of the stone and draging it back a few times.
This will help keep the blade sharp and make shaveing the wheels better.

As for the Adjustment screw winding back.
It makes me think the blade is lose fitting in the tool.
To fix this use two sets of pliers and bow the blade slightly where the slot is in the top of the blade.
This will help with the blade slop.. and the adjustment screw from winding back.
These mods can be seen on the Derby Worx web site. ;)
Whoda.
What type of automobile can be spelled the same forwards & backwards?
jacksdad
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Re: Son of a Pickle

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Mark - that makes sense. Tightening the blade in the slot has to make it hold better. I did get real good at adjusting it by holding the spring, but bowing it would definitely fix the excess play. I found that after sharpening the blade on both sides to give it a double bevel, it was sharp enough to take off an incredibly thin layer. I had to be careful when I handled it or it would definitely have cut me. The wheels ended up round to a tolerance of less than a thou as best I could measure. Of course, with this being his last year I'm not sure I'll be shaving any more wheels - and I do believe I'm fine with that :)
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