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scales for tweaking?

scales for tweaking?

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Old 01-22-2007, 05:07 PM
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Default scales for tweaking?

I've been told that you can use scales for tweak. I do believe that it can be done but my question is how big of a scale in grams should i get? What are the weights of touring car, 1/10 scale truck and buggy? Is offroad balancing necessary? Thanks for any input. Jeff
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Old 01-22-2007, 06:02 PM
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When balanced your car will have somewhere between 350 - 400 grams per corner. Basically the weight minimum for stock rubber is 1525 grams (foam 1419). Divide that by 4 and you get around 380 grams. Obviously when you start they will not all be equal so add a hundred grams or so and you should be ok for a set of scales.
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Old 01-22-2007, 06:18 PM
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thank you for your input! I appreciate every bit of it. Do you think that this is a good alternative to a tweak station? Thanks again, Jeff
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Old 01-22-2007, 06:49 PM
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I use scales for tweek it works great! It works better than a tweek station becuse you can "see" all 4 corners at the same time.I bought 4 scales from "The Source" for around $20 each.Don't expect every corner to be exatly the same,10-15 grams differance seems to be ok.
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Old 01-22-2007, 07:09 PM
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Doesn't your car have to be pretty well balanced at all 4 corners for this to work? If your car was out of balance left to right or front to back or both yet had no tweak the scales would read differently, right? My thought would be that you would have to un-tweak it on a tweak station such as the Integy, then balance the car using weights. Once balanced then I would think you could use the scales for tweak.

This is just my thoughts. Maybe someone who knows how to use scales to balance/tweak a car can elaborate.
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Old 01-22-2007, 07:18 PM
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I just did a search in this forum for scales and found some old discussion from what sounds like pretty knowledgable racers but now i'm more confused than when I started. Wish the RC gods would explain this whole setting up a car in easy to follow directions. Kit instructions say nothing about most of the things discussed here and I just the car to go straight and handle predictably.
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Old 01-22-2007, 08:03 PM
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Default scales

If you use two scales only, and a level block at the other end of the car, then the scales work just like a tweak station. You make the neccessary adjustments on the car to make the scales read close to the same just like you would make to center your bubble on a tweak station. I make sure my table is level and that the block I use is the same height as the scales. Mark the center of the scale as well to ensure that you get the tires centered.
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Old 01-22-2007, 08:31 PM
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Originally Posted by SlamMan
Doesn't your car have to be pretty well balanced at all 4 corners for this to work? If your car was out of balance left to right or front to back or both yet had no tweak the scales would read differently, right? My thought would be that you would have to un-tweak it on a tweak station such as the Integy, then balance the car using weights. Once balanced then I would think you could use the scales for tweak.

This is just my thoughts. Maybe someone who knows how to use scales to balance/tweak a car can elaborate.
Michael I believe you are correct with those assumptions. If a car is not balance you will not be able to check for tweak on four scales.

My scale was around $30 dollars at Staples. Guys use four of them just like the one I have to balance cars. I don't want to spend $90 more dollars to balance ny car. They are digital scales that wiegh in lbs. and grams. Upto 5 lbs in wieght each scale. Made by pelouze. Model # sp-5. hope this helps.
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Old 01-22-2007, 09:04 PM
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With scales or a tweak board the goal is the same, you want your left and right weight to be equal, or as close to it as posible. with 4 scales you can also tell if your car is equal from front to back. Being equal from front to back isnt as iportant, but if your car is pushing or spining out and you want try moving weight forward or back it is a more acurat way to do it. The nice thing about the 4 scale set up is when you do get your car working perfect for a certain track, you can make a note of the numbers. And the if you ever need to replace a part or take somthing apart for maintaince, you can recheck the numbers to make sure the car is perfect for the next run. Also, alot of the team drivers use scales and if you want to try and copie there setup, you will need the scales to do so. Two scales is fine also. Just remember the most important thing is getting the weight on the left and right side of the car as close to equal as posible. This way your car will turn equally in both derections. Also just as important is to make sure your camber and caster is equal on both sides of the car. I hope this helps you out, AL
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Old 01-22-2007, 09:29 PM
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i have been using 4 scales to set tweak for almost 2.5 years now. when using them you have to remember you want the cross weight to be the same. (left front + right rear = right front + left rear)

sent your droop and ride height. then put your car in race ready condition( if you use sway bars you may want to remove them) on the scales.

you will notice that all 4 scale generaly will close but not he same.

Just for example............ say the left front is 11.9 oz right front is 13.1 and left rear is 12.7 right rear is 12.3 your cross weight differnce is 1.6 oz.

now can adjust the shock collers to correct it, in this instance you would tighten up the left front and right rear and loosen up the right front and the left rear... in small incorments ( sp) untill you reach equal cross weight.

personaly i use oz.... you can use grams but it may take longer to reach = cross weight

it can be a bit confusing but once you get used to it, it is a very usefull tool
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Old 01-22-2007, 09:33 PM
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Originally Posted by Stratus Racer
Michael I believe you are correct with those assumptions. If a car is not balance you will not be able to check for tweak on four scales.

My scale was around $30 dollars at Staples. Guys use four of them just like the one I have to balance cars. I don't want to spend $90 more dollars to balance ny car. They are digital scales that wiegh in lbs. and grams. Upto 5 lbs in wieght each scale. Made by pelouze. Model # sp-5. hope this helps.
hey paco you are more than welcome to use my scale setup any time at socal,
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Old 01-22-2007, 09:44 PM
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Try this thread

http://www.rctech.net/forum/showthre...hlight=scaling
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Old 01-23-2007, 09:31 AM
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I just read that whole thread. Thanks Speedie. So it's my understanding that you really need to set your L/R and F/R balance first using the chassis weights. Then you balance out your FR/RL and FL/RR weight (known as wedge or tweak) by adjusting the shock collars.

My next questions would be what is the effect of adjusting the wedge (tweak) without proper L-R and F-R balance? How important is it that the L-R and F-R balance be as close to 50/50 as possible? How much is too much when setting up the car to have more weight in the front or rear?

Great topic. I can't wait to try some of this stuff.
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Old 01-23-2007, 11:30 AM
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When setting tweak on scales, all you are doing is making sure the sum of the opposite corners are equal. Example LR+RF = LF+RR.

If the static weight of the chassis is balanced, LF=RF & LR=RR as well.
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Old 01-23-2007, 12:07 PM
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I read a couple of your posts in some other threads and I get the impression you know what you're talking about, Jack.

What about running more weight in the front or rear? Is 60/40 too much? Is it more common to run more weight in the front or back or are you best off running at 50/50?
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