Questions for the Pro's & my comments & requests.

Secrets, tips, tools, design considerations, materials, the "science" behind it all, and other topics related to building the cars and semi-trucks.
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sporty
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Questions for the Pro's & my comments & requests.

Post by sporty »

Okay,

Since some consider me knowing alot and a pro. However I don't think I am. But I do know We do well and We seem to know a good bit of info.

I have been tossing a few things around in my mind for awhile now. So I thought why not ask or comment on about it. After all its a forum.

Some say RR is faster than strait runs. Well Dang it, I have yet to do a RR well enough to see it.

Tried allot these past few months. There simply has to be something Im not getting or that I'm over looking.

Now this is a wooden track and We race on wooden tracks. Some say RR is more for metal tracks.

But I did have to try.

I would really like to know how the comparison and testing has proven it faster ?

Yet I think what I would also like to talk about and know is--.

Sorry, got to mention leagues here for a bit.

I am really curious to know, how many cars a league racer builds before they get a super fast one ?

Simply saying we build allot of cars this year. Out of all those cars. There was one/two that were pretty darn fast.

But the differance in weight placement was so small from one car to the next. I simply can not for the life of me believe that it can be done with just one or two cars.

Gees, it seemed like .003 or .005 could yield the differance of a slow one to a fast one. Thats with my already having a very good idea on how to build a fast car.

Pretty hard even for me, to add weight even knowing where I want it and trying to get that accurate in regards to weight placement.

Especially on a repeat, duplicate build process.

Now I don't have a timer on the test track I'm using, so this is likely a pretty big draw back.

But I was still able to test by comparison. Place and tape the weight and move and adjust until I got it as fast as it was gonna go.

I could also compare them by the win or loss or distance between the other car for the comparison.

So, not all was lost.

But I wanna ask to the vendors out there, to really put some good videos out there on their sites.

I have yet to find a great wheel polish prep video and a really good axle prep video.

But a alignment video is what is needed the most !!

A 5 or 10 minute video on each area, would be a great help !!

I bought and viewed some of the videos out there for sale and I did not find one that dealt with those area's very well.


There our so many websites out there selling PWD stuff these days. I here by ask them to have more videos and instructions on there retail sites.

Sportys- Gripes

I got some, I feel it's time for me to share them.

Please, stop posting over the top stuff. We all know phyics and other key info can help with PWD. But keep it in perspective and real balance in regards to pwd.

I enjoy helping people and I am far from knowing it all or perfect. But I think when I spend alot of time resolving and clarifying some of the out of this world posts. It does grow old at times.

so try and think a little more common when you post. Not everyone here works for nasa or took phyic's.

We need to be realizing that the average and more typical pinewood derby family knows very little and is never going to go to that level that many who post here will go to and do.

I do feel this would also make newer and less expierenced pwd posters and viewers to sign up and come and ask and post and learn and grow and share with all of us.
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frontosacam311
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Re: Questions for the Pro's & my comments & reques

Post by frontosacam311 »

In regards to RR being faster than a straight runner, the way I understand it is a RR will put out more consistent times. A straight runner may achieve a faster speed in a race or two but overall the times will have a greater spread than a RR. In certain types of racing where your times are averaged consistency is the key.
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Stan Pope
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Re: Questions for the Pro's & my comments & reques

Post by Stan Pope »

sporty wrote:We all know phyics and other key info can help with PWD. But keep it in perspective and real balance in regards to pwd.
This is an interesting concern.

Part of the price for using my answers is digging the "hows" out from among the "whys."

I impose that "price" because I feel that exposure to the "whys" is an important part of the value of PWD racing for youngsters and their mentors. Winning races is not the reason for PWD. That is the "bait" that we use to induce youngsters (and oldsters) to participate. Youngsters derive less value from "following a cookbook" than from "building from understanding."

Whether I am right or not in this position is immaterial. It derives from my values and dictates the form of my participation in the forum.
Stan
"If it's not for the boys, it's for the birds!"
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sporty
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Re: Questions for the Pro's & my comments & reques

Post by sporty »

frontosacam311 wrote:In regards to RR being faster than a straight runner, the way I understand it is a RR will put out more consistent times. A straight runner may achieve a faster speed in a race or two but overall the times will have a greater spread than a RR. In certain types of racing where your times are averaged consistency is the key.
It's still something I'm working on and the reply certainly helps.
Stan Pope wrote: This is an interesting concern.

Part of the price for using my answers is digging the "hows" out from among the "whys."

I impose that "price" because I feel that exposure to the "whys" is an important part of the value of PWD racing for youngsters and their mentors. Winning races is not the reason for PWD. That is the "bait" that we use to induce youngsters (and oldsters) to participate. Youngsters derive less value from "following a cookbook" than from "building from understanding."

Whether I am right or not in this position is immaterial. It derives from my values and dictates the form of my participation in the forum.
I do not base everything on speed myself. That was my comment that is general to no one person in specific.

I just deal with phone calls and PM, from other forum members who are often more confused on some lingo and replies. Then what I feel it helps.

I always feel that the same information can be related to a newer person in a simpler format, yet still achieve the same outcome.

It's certainly not about alienating people. It's about saying to all that if the message is loosing the common goal it was intended then it is actually counter to what was the intended goal and outcome.

Then as those newer members become more advanced in lingo and in understanding then they are ready to understand more complex information.

Sporty
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Re: Questions for the Pro's & my comments & reques

Post by derby doc »

Sporty..When I won the modified title at pwd racing, I built 1 car. I got lucky with it, and ran it for 12 months straight. During those 12 months, I ran 4 sets of the Derbyworx RS wheels, and I think that a fresh set helped me about every 3 months since the aluminum track can wear down a set of thin wheels. RR has definately helped me, and I went about 5 months undefeated. I started to get a little burned out during the mid year, and I was VERY lucky to clinch the top spot by the end of the year. Im pretty sure that everyone that gave me a hard time each month were using the RR method.
I agree that a straight runner might give a faster time now and then, but a RR is more consistent, and will allow easier tuning between runs when your testing it.
I hope this helps.
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sporty
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Re: Questions for the Pro's & my comments & reques

Post by sporty »

Derby Doc,

the comments and info are well welcomed and I am gratefull.

I need to find where I lack, that just one build could perform so well.

Perhaps the struggle I will face in the process of gaining and learning will in the end come with great reward.

Thanks,

Sporty
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derby doc
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Re: Questions for the Pro's & my comments & reques

Post by derby doc »

Sporty, I am very blessed with having an awesome workshop. Having my families machine shop with lathes, and milling machines, etc helps me a ton. Ill be more than happy to help out in any way possible. Ive been machining, and fabricating stuff in a machine shop enviorment since I was a teenager, and I stumbled across this awesome sport of pinewood derby with my daughter. I now have a 4 year old son in AWANA, and I cant tell you how much I enjoy helping out those little kids in his age group.
If I had to choose 1 single thing tha made my cars faster, it would be alignment. I can turn a 4th place car into a winner just by tweaking, and tuning on a car.
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Re: Questions for the Pro's & my comments & reques

Post by PWD_addict »

sporty wrote: But a alignment video is what is needed the most !!

A 5 or 10 minute video on each area, would be a great help !!

I bought and viewed some of the videos out there for sale and I did not find one that dealt with those area's very well.
Sporty--
Last year (second year of car building), when building the fleet (4 cars) of PWD cars with children and Godchildren, I finally had the "a-ha" moment of alignment. I helped build and align the three fastest cars in our District (one was a sibling car) and the fastest in my Godson's pack. All were railriders. If you don't understand alignment, you need to read and reread Stan's section on it and anything else on it until you do. If we sat down together, and I could draw pictures and stuff like that, I may be able to show you. However, it is very difficult to explain in written form only.

Let me try:

Think of one wheel, in two dimensions only for now.

The following punctuation marks represent the alignment of the axle. The capital “I” represents the body of the car as seen from the top looking down at the right side of a PWD car.

If the axle is straight out from the body (perpendicular), it is represented with a double hyphen: I–

If the axle has the head bending forward from the perpendicular (toe-in), it is represented with a front-slash: I/

If the axle has the head bending backward from the perpendicular (toe-out), it is represented with a back slash: I\

From Wiki on Toe (automotive): Positive toe, or toe in, is the front of the wheel pointing in towards the centerline of the vehicle. Negative toe, or toe out, is the front of the wheel pointing away from the centerline of the vehicle. Toe can be measured in linear units, at the front of the tire, or as an angular deflection.

Imagine a wheel on the end of these punctuation marks (axles).
I— makes the wheel go straight. It doesn’t move away or towards the body either.

Next it gets hard:

I/ makes the wheel turn towards the body and as the wheels moves, it also moves toward the body.

Understanding why it moves towards the body and why it steers is crucial to understanding alignment. If you need to, put a wheel on an axle and toe it in (axle direction should be the same as the forward slash with your fingers representing the car body) and move it forward slowly providing a little weight on it (use junk wheels/axles) leaving room to see how the wheel is moving. It should move towards your fingers. Make sure you’re trying to move the wheel straight (the axle should be at a 45 degree angle from the direction of travel). I haven’t tried to do this and it may not work the way I expect. 45 degrees may be WAY too much but if you have it forward from the perpendicular, it should work. However, it will work that way on a real PWD car.

Now, do the opposite.

I\ makes the wheel turn away from the body and as the wheel moves, it moves away from the body.

Now, you have to think in the other dimension. The capital I is now the right side of the car as seen from track-level looking forward from the back of the car. Imagine a wheel on the end (the right side) of the punctuation mark (axle).

I—makes the car go straight and the wheel doesn’t move toward or away from the body.

I/ is the axle head pointed up from the body (negative camber). The wheel will go straight but will migrate towards the head of the axle.

I\ is the axle head pointed down from the body (positive camber). The wheel will go forward but will migrate towards the body of the car.

From the Wiki on Camber angle: If the top of the wheel is farther out than the bottom (that is, away from the axle), it is called positive camber; if the bottom of the wheel is farther out than the top, it is called negative camber.

If you are still with me, you should be able to imagine in your mind now a single axle in three dimensions.

For me, I try to take some of the unknowns out by providing negative camber on the rear axles by bending it up slightly ( I/ as viewed from the back of the car at track level). Then, we can rotate the axle head until we get the desired effect. If it is straight out from the body (I— as seen from the top) and ( I/ as seen from the back), the wheel should migrate out to the axle head slightly and not steer the car.

We do the same for the front wheel (three wheelers only) but want a little bit of “I/” (seen from the top) to provide steerage to the rail, AND a little bit of “I/” (seen from the back) to keep the wheel away from the body. The more you rotate the axle clockwise from 12:00 (as seen from the side), the more steerage towards the rail you have.

Imagine what happens as you rotate the slightly bent axle in the axle hole and what that does to steering and wheel movement. If you can imagine it in your head, you are in great shape!

I hope that wasn’t a total rant and it provided value.

BTW, if you have I~, you're in trouble. :mrgreen:
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sporty
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Re: Questions for the Pro's & my comments & reques

Post by sporty »

Good info.

I have my own video I share to help others with video. I'm very good on alignment.

Just still getting that RR down is the issue. I can't get it faster than my other method.

For info-

We hold two track records at two local packs, under their rules.

3rd place at council two years ago. 1st and 2nd place at council this past year.

Average time spent on fine tuning alignment per car, 10 hours.

This 2009 year we were able to become faster than the previous year. we will have to wait and see if it's fast enough !

Anything can happen, Dropped car, ruff stop section, car rolls off the table. Someone just plain old faster.

Sporty
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