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Weight Balancing With Scale

Weight Balancing With Scale

Old 10-22-2004, 04:36 AM
  #16  
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Originally posted by modeltech
... if your 4 scales are not calibrated to measure exactly the same (i.e. over deflection) then the results will be misleading.
Thats why the use of a single scale, is excellent and genious. By design, it eliminates an eventual mis-calibrating.
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Old 10-22-2004, 05:18 AM
  #17  
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Default weight balancing a TC3/4

going back to the start of this thread, you cannot weight balance a shaft drive car like a TC3 to set tweak. The reality is that the torque of the motor affects it. Every good AE driver I have ever seen has set their tweak from feeling how the car runs on the track.

weight balancing definitely does work with 12th scale or most belt-drive sedans
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Old 10-22-2004, 05:42 AM
  #18  
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Barry, that's interesting.

Not that I have a shaft car, but I would assume that it would be a good staring point to balance it by weight, and afterwards work with the track feel, based on the knowing of to which side the torque works... Right?
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Old 10-22-2004, 05:49 AM
  #19  
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good point

it certainly doesn't hurt to start with the weight distribution correct
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Old 10-22-2004, 06:24 AM
  #20  
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actually i have had that opinion about shaft cars for some time now. since the motor is mounted in such a way that torque becomes a factor that you should consider when tweaking a it.
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Old 10-22-2004, 07:11 AM
  #21  
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All car layouts suffer from some torque reaction to some degree, shaft cars side-side, belt drive cars front-rear.

Its just more of an issue with a shaft car since pronounced changes of load on the tyres side-side as you go on/off throttle will immediately affect the cars direction/handling/steering depending on what it is doing at the time.

If you set the tweak to counter it this will just exagerate the difference between on/off throttle............it is still far far better to have the car laterally balanced to start with.
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Old 10-22-2004, 01:24 PM
  #22  
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Tires are probably the biggest percentage of the unsprung weight of a car. The tire itself is part of the total spring forces on the car. A car should be scaled as it is raced. Not all tires weigh the same. Different componds and inserts, different size foams is all going to make a difference. Yes the Integy system works fine for balancing the car out. But if your going to spend all of that money a person should just go a little more and buy 4 scales. That way a car can be checked with out taking it apart.

As far as calabrating them. Unless you buy some junk they will weigh within a gram. Thats more than fine for our application. Alwayse use the same scale on the same corner for consistant readings. Not that it would matter to us but just for peace of mind and its too easy to do. The important part is making sure they are on a flat level surface. I have seen alot of full scale racers try to scale a car on uneven cracked concrete and wonder why thier car is way off every time they scale it. All that is needed is to make sure the height of all 4 scales is the same set them on a flat level surface and scale away.

As far as tweak is concerned Barry is right about the feel of tweak on the track. The scales would just give you the best possable chance of having it right as it hits the track. Then if it feels right to you on the track you have a means of repeating the feel of the car in case of a hard hit or replacing parts and changing springs.

I just use my scale to balance the car left to right and to get the front to rear percentage where I want it. I then set my ride height. Not just close tho. I get right down with my little eyeball and look under the chassis and get it perfect. Not within a half a mm but perfect. Then I throw it on the track without setting tweak per say. Its alwayse been perfect every time. I attribute alot of that tho to the awesome chassis I have tweak proof and nice and flat.

I see alot of people trying to set tweak using the exacto method. While this is fine for a 12th scale a TC's downtravel is limited by droop screws. So if the droop is not exactly and I mean EXACTLY perfect side to side. The tweak will be off.

Sorry for the longwinded comments.

Last edited by Speedie; 10-22-2004 at 11:22 PM.
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Old 10-22-2004, 03:11 PM
  #23  
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Originally posted by SpeediePHATT
Actually tires are probably the biggest percentage of the sprung weight of a car. How can something hanging off the end of an arm that is controled by a spring be unsprung?

.............. I build and race cars for a living. this is one of the biggest things I see in RC that has crossed over and has helped me alot.
I have no desire to enter into an argument over this, but I would suggest that for someone who claims such a background, you might wish to go away and study up on this a little........you might learn something that you obviously don't appear to correctly understand right now

To get back onto topic, the point of using scales is to measure the corner weights of the car and adjust the weight distributions so that they are as near equal left/right as is possible. Weighing the wheels/tyres has nothing to do with this what so ever.

Last edited by modeltech; 10-22-2004 at 03:21 PM.
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Old 10-22-2004, 03:59 PM
  #24  
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You are right. My thinking is correct it just dont alwayse come out the right way. I edited my post to correct that.
If I am wrong about needing tires tell me why. Like everyone here I am here to learn. I am the first to admit I know nothing. And alwayse hope to stay that way. The man who knows everything knows nothing. Thanks

Not everyone is only trying to balance the car left to right. Oval guys not at all, and some want to use them for tweak setting. The wheels still need to be on the car. IM not saying the Integy system doesnt work. It just is only good for one thing left to right. A 4 scale system does alot more better. The car is not raced with 3 perches under the axles and a scale. Im not telling anyone they have to listen to me this is my opinion.

Last edited by Speedie; 10-23-2004 at 02:09 AM.
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Old 10-23-2004, 09:02 AM
  #25  
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Default 4 way!!

Using one scale will tell you how much the car weighs and that's about it Not very useful as far as setting it up. I use to race real cars and when there was a handling problem the first thing we did was scale it! It's not that expensive to build a four way scale about double the price of a good tweek bar and a lot more accurate! Here is a pic of mine but Ill see if I can find some better ones
Attached Thumbnails Weight Balancing With Scale-imga4134.jpg  
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Old 10-23-2004, 11:04 AM
  #26  
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Hey thats cool. Do you have some better pics of it?
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Old 10-23-2004, 11:47 AM
  #27  
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I think there are a few on my website "Da Hellion RC" Heres another one
Attached Thumbnails Weight Balancing With Scale-rc%2520car%2520stuff%2520011.jpg  
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