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Post by 68camaro on Feb 1, 2007 8:14:49 GMT -6
Newbee here on board! If my completed car swerves to the right pretty dramatically where would I start the adjustment process?
On a second car it tracks to the left. Is there a rule of thumb that to fix these you start with a certain wheel on side (or opposite) that it veers towards?
Thanks in advance.
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maxx
Addicted to Speed
Posts: 83
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Post by maxx on Feb 1, 2007 18:25:29 GMT -6
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Post by slkrnsntracing on Feb 1, 2007 20:31:11 GMT -6
Newbee here on board! If my completed car swerves to the right pretty dramatically where would I start the adjustment process? On a second car it tracks to the left. Is there a rule of thumb that to fix these you start with a certain wheel on side (or opposite) that it veers towards? Thanks in advance. 68camaro, First of all, I take it that you are running on 3 wheels. Normally that would mean that your touching front wheel is aimed to hard to the right. Normally I try to align my cars so the touching front wheel goes to the rail, but I don't want it to swerve to the rail. I usually roll my cars on a smooth surface, and when the car veers gently (say 1" in 3 or 4 feet) so that the touching front wheel would go to the rail, I call it good. The main thing is that once it gets to the rail, it stays there. After you get your front end to the rail, then you need to make sure that the rear end runs straight also. It would be best if neither rear wheel rubbed the rail, but I'm usually happy if the back end doesn't swing to and fro while it's going down the track. A lot of guys use a dressing mirror about 4 feet long, and block one end of it up about an inch so the car rolls slowly, and you can watch what the car does. Hopefully somebody who knows what they are doing will jump in and help out. Good Luck. I like your name. Where did it come from? Phil
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Post by Kevin on Feb 8, 2007 18:42:36 GMT -6
Sorry, but I would not do what slk suggested. That creates way too much friction. This is a simple fix if running on 3 wheels.
1. Put a tick mark on the top of the axle at 12 o'clock with a sharpie so you know how to put the axle back into the car body. Also mark where axle meets the car body.
2. Put the axle in a vise with tick mark at 12 o'clock at exactly the point where axle would meet car body.
3. If car tracks to the left bend the axle the opposite direction by tapping one time with a hammer at the head of the axle. I mean tap not hit. This is a very slight bend.
Take it out and try it. You may have to do this 2 or 5 times to get it right on.
The bottom line is the car must run straight or you will lose.
Kevin
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maxx
Addicted to Speed
Posts: 83
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Post by maxx on Feb 8, 2007 20:48:23 GMT -6
Sorry, but I would not do what slk suggested. That creates way too much friction. This is a simple fix if running on 3 wheels. 1. Put a tick mark on the top of the axle at 12 o'clock with a sharpie so you know how to put the axle back into the car body. Also mark where axle meets the car body. 2. Put the axle in a vise with tick mark at 12 o'clock at exactly the point where axle would meet car body. 3. If car tracks to the left bend the axle the opposite direction by tapping one time with a hammer at the head of the axle. I mean tap not hit. This is a very slight bend. Take it out and try it. You may have to do this 2 or 5 times to get it right on. The bottom line is the car must run straight or you will lose. Kevin 68 this is a valid way to align your cars but as far as ignoring what SLK has to say,that is just an opinion.The technique that SLK was referring to is called railriding and despite what Kevin thinks it happens to be a proven method to get down the track very quickly. There are more than a few experienced racers here that use this technique exclusively.If you search these and all the other forums you will find the same consensus. Now that doesn't mean that you can't make a car that will go straight and not be fast,cause in theory that would be the ideal way to do it.But sometimes theory doesn't always apply.One of the best places to get started on learning something about alignment would be at Stan Pope's on line book.Here is a link.Alignment is one of those things that is well worth taking your time on,the effort will pay off handsomely. members.aol.com/standcmr/lbw_apl.htmlHope this helps, Maxx
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Da Pine Racing
Head in the Pine
kamaniwannaracedakinepinekah
Posts: 172
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Post by Da Pine Racing on Feb 9, 2007 19:35:36 GMT -6
3 wheels are better than 4. I like to get the car done, wheels & nails prepped. Glue them babies in & start rolling & rolling & rolling & rolling & rolling..........look at the rear wheels & how they turn on the nails. If they hug the body when goin forward, then hug the nail head when goin backwards----Houston,we got a problem. there is a toe-in situation and vise versa if it's the other way around (Toe-out). Get them rolling true. Then if it still pulls left or right, adjust the front wheel until it goes straight. Oh yea. camber is a factor also.
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Post by 68camaro on Feb 23, 2007 9:13:11 GMT -6
My sons car runs on all 4, the track will be wooden, and the car tracks right quite a bit.
Is best method to put in vice as explained above and tap axle? If so, should I start with front right tire since it is tracking right?
Bye, the way my son did win his Pack's rank which was on a metal track. Interstingly, our car was slowest to start but once it hit straight it passed everyone.
Tracking problem is due to requirement to use "less" modified wheels which are rule at district level.
My name comes from our 68 RS ragtop, red on red with white Z-28 strip's.
Thanks
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Da Pine Racing
Head in the Pine
kamaniwannaracedakinepinekah
Posts: 172
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Post by Da Pine Racing on Feb 23, 2007 11:30:46 GMT -6
Hey 68, On a aluminum track the Rail Rider is a fast way to get down the track.
On a wooden track I would say a straight runner is the way to go.
I would start at the back axles & make sure you don't have a toe-in or toe-out situation. If rear axles are straight then start adjusting the front. If you lift one of the front wheels so it's not in contact with the surface, it is much easier to adjust to go staight & also reduces friction.
There is also a thread about canted or not to cant axles thats been pretty active lately with some interesting stuff on it.
Congradulations to your son on his pack win ;D
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maxx
Addicted to Speed
Posts: 83
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Post by maxx on Feb 23, 2007 12:03:55 GMT -6
Hello 68camaro,
My sons car was also limited to being a 4 wheeler with similar wheel mods(lightly sanded tread)this is what we did.
First determine which front wheel is the dominant wheel.To do this push down lightly in center of nose of car and determine which wheel if any is carying more weight.More often than not when you push down you will be able to notice that one side of the car will move slightly down,the side that moves is not the dominant wheel.
Remove the dominant wheel and align your car however you are planning,when happy reinstall your dominant front wheel and then align car again making adjustments to the dominant wheel only.
What we noticed this year with our test track is that a 4 wheel car that is set up to rail ride is a little faster if you steer the non dominant front wheel into the rail,this is the exact opposite of what you would want with a 3 wheel car.
What you might want to do before you get started is roll the car on a flat surface and make note of the drift or steer that the car already has for a reference point,then you can make slight changes from there.
Hope this helps,
Maxx
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Post by 68camaro on Feb 25, 2007 13:36:56 GMT -6
Thanks to all, we came in 4th at the district and followed all the rules, at least one car ahead of us didn't follow rules and many others didn't as well, I brought this up before race started, but track officials wimped out. Our race results: 4 times - 1st 3 times - 2nd 2 times - 3rd
In the last two heats all the cars were very close, I am sure if I widened wheelbase and/or raised one wheel, I easily could have picked up extra time, but I thought track officials would actually enforce the rules.
I did make one mistake though. I was told track was wooden so I reset my weights based on this (Our Pack used metal track which we won rank). After I checked in, I was mortified to see track was metal. If I had known this I would not have changed weight distribution. This probably cost a little time:( Lesson here is to verify track myself next time before registering.
No problem though, it was still a thrill. Already we are talking about next years car and my son was very happy with results.
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Post by johnd900 on Apr 1, 2007 20:44:01 GMT -6
Great thread guys! Tons of info for this rookie.
68 Crongrats on the getting to the districts and placing 4th.
Well my little guy (Tiger cub) and I didn't fare well at all at our first crack at this. Unfortunately I didn't have the time to test the car. I spent my time prepping the axles and wheels instead of making sure the cars run straight. I think that I took too much material off the axles as they seem to "flutter" as I spin them with my finger. Not sure if fluttering occured while traveling down the track though, I assume so. His cool little truck was quite slow. I would like your opinions to what may have happened. Here's my thoughts: 1. The truck pulled left I would say 1" every 2'. (I found this after the race when I ran it down a board back at home.) 2. The wheel flutter I believed may have caused the truck to go side to side down the track. 3. It was a truck design so there was probably more weight up front than there should've been. (I knew this may hurt us, but this was what he wanted and I didn't want to push win, win, win thought process on him.) 4. The weight was only 4.9 oz. 5. I did an extended wheel base but must not have drilled a perfect hole on the right front axle as the wheel is tipped out at the top. (As I recall though this wheel sat up nicely for a three wheeler, but our pack didn't allow that, so I had to get the wheel to come down...) 6. Inexperience, just not knowing what to expect.
That afternoon we both came home with our heads hung low. He was very hurt once he learned he had been eliminated after the first round (4 heats). I beat myself up the rest of the afternoon feeling as though I let him down. I know this was our first time but I really thought we would have faired better than we did. My heart just sank as I saw the truck go down the track in the first heat. He looked right up at me and asked, "Dad why is my truck so slow?"
Well we're both determined to come back strong next year, and I'm starting my homework now. Thanks so much if you read all this. This was probably more therapudic for me than anything.
JohnD900
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maxx
Addicted to Speed
Posts: 83
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Post by maxx on Apr 1, 2007 21:30:48 GMT -6
Hello Johnd900, The most important thing about your son's derby this time around was the time the 2 of you spent together .You may not have done as well as you were hoping,but is sounds like you guys are determined to do better.That is the motto right?With that kind of heads up attitude you and your son are already winners,keep up the good work ;D.And if there is anything I can help you with don't be afraid to ask. As far as what happened with your sons truck it seems like you already have a good handle on that.All the things you mentioned in your post contributed to the trucks performance. 1.The unknown amount of steer is not good thing unless you get lucky.also with 4 wheel car if you set it to steer,both wheels need to be doing the same thing. 2.The wheel flutter or orbiting is definitely not a good thing.Reducing the axle diameter excessively could cause this but so could a number of other things.The most likely being the condition of the wheel bores and what you did to prep them.Wheel bores need to be polished as well as the axles. 3.The truck design is OK but you have to make an extra effort to remove as much wood as possible so that you may add weight to the rear.Hollowing out the front of the truck would have helped you. 4.Yes you should always try to maximize your weight.One of the easiest ways to do this is to go to the race knowing that the car is a little underweight and plan to add a small amount at the tech inspection,a popular way to do this is to have some small holes drilled in the bottom of truck to add small tungsten beads or putty,or even some lead tape. 5.The extended wheel base is great idea but you need good tools to drill accurate holes.The Pro Body Tool works well for this and you would also be able to do it with a decent drill press.The wheel top being tipped out at the top was very bad.This would cause the wheel to migrate towards the body causing a breaking effect between the body and the inner wheel hub.This condition was obviously made worse when you had to correct your non touching wheel issue.If you bent same axle further down to make contact the force applied at the body and inner hub would have been increased further. 6.The experience will come,the best thing you can do there is make sure you get a copy of the rules you have to build and race by and make sure that you are 100% sure what you are allowed to do and not do. Hope some of this helps. Maxx
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Post by ProQuest on Apr 1, 2007 23:09:53 GMT -6
John:
You'll get solid advice from Maxx and many others on this board. Keep asking questions and try the suggestions you find here and your son and you will do great next year. One thing you might consider is sending a car to WIRL or PWDracing for their monthly proxy race. That way you can get more experience building and racing, you can see what works and what doesn't, the vets can actually see your cars run and offer specific advice to correct problems, and all the while you'll be having fun.
Couple of quick tips: First, less is more in pinewood derby. The less your car body weighs before adding weight, the better. Its hard, but not impossible, to make a car that looks good and is light (before adding weight), but that's the challenge if you want to go fast. Shoot for wheels, axles and car body to weigh 1.5 oz. If you can do less, great. I suspect that some of the vets are running car bodies that weigh under an oz.
Second, allignment is critical. Three words: Pro Body Tool. Unless you have a very accurate drill press, and really, really know what you are doing, buy and use the pro body tool. This is a good rule regardless whether you are running a standard wheelbase or an extended wheel base.
Third, run on three wheels if your rules allow. Raise one front wheel 1/16" higher than the other.
Fourth, good wheels and axles are also extreemly important. One of the worst mistakes inexperienced racers make is to over prep wheels and axles. If you think you might have removed too much material from the axles, you probably did. Unless you are buying wheels and axles that are turned/prepared by a professional, get the Derby Worx pro wheel shaver XT II to true the wheels, and get a good axle prep kit from a company like Maximum Velocity.
These are just a few thoughts to get you started. I'm no veteran, but I think most of the vets would agree. If any reading this don't I hope they'll post and give you the benefit of their greater experience than mine.
Good luck, and think how great its going to feel next year when your son's car is among the fastest in the pack.
ProQuest/Steve H.
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Post by parrish on Apr 2, 2007 10:58:15 GMT -6
Sorry, but I would not do what slk suggested. That creates way too much friction...Kevin I would tend to disagree with Kevin on this one... Some of the fastest builders tune this way, it's hard to disagree with their success I do agree that you should be using the Pro Body Tool and running on 3 wheels if allowed.
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Post by JOKER on Apr 2, 2007 22:11:00 GMT -6
Sorry, but I would not do what slk suggested. That creates way too much friction...Kevin I would tend to disagree with Kevin on this one... Some of the fastest builders tune this way, it's hard to disagree with their success I do agree that you should be using the Pro Body Tool and running on 3 wheels if allowed. SLKRNSNT & PARRISH are right......stick with their advice. Here is a little info to validate the comparison of the 3-wheel RH to traditional straight alignment: (Perhaps it is not faster, but it will be more consistent!)- Once in a while the straight aligned car may have that perfect run where it rarely touches the rail & will win a heat against the RH.
- However, if you have 6 runs between a good RH & a good straight aligned car - The RH will come out on top.
- Think of it like this - the RH gives added stability to your car & will run in a straight line to the finish line - Even though it rubs on the rail - it is only from the DFW which is the lightest part of the car - very minimal energy loss.
- Even the best straight aligned car is going to bump the rail a few times during each run - each bump from this type of car results in a greater energy loss - because it hits the rear wheels where your car is heavier and will have more breaking action - also the drifting back & forth results in a longer distance to the finish line - rather than the straight path of the RH!
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Post by johnd900 on Apr 5, 2007 9:29:04 GMT -6
[/li][li]Think of it like this - the RH gives added stability to your car & will run in a straight line to the finish line - Even though it rubs on the rail - it is only from the DFW which is the lightest part of the car - very minimal energy loss. [/li][li]Even the best straight aligned car is going to bump the rail a few times during each run - each bump from this type of car results in a greater energy loss - because it hits the rear wheels where your car is heavier and will have more breaking action - also the drifting back & forth results in a longer distance to the finish line - rather than the straight path of the RH![/list] [/quote] So on the RH (Rail hugger?) is it only the front wheel (Dedicated Front Wheel) that is touching the rail and not any of the rear wheel?
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Post by warthog on Apr 5, 2007 9:39:53 GMT -6
So on the RH (Rail hugger?) is it only the front wheel (Dedicated Front Wheel) that is touching the rail and not any of the rear wheel? Yep BTW -DFW=Dominant Front Wheel (could use dedicated, i guess)
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