Help finding COM chart please

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davet
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Help finding COM chart please

Post by davet »

I once saw a nice chart on here that listed various wheelbases and their COM location vs DFW weight. Can't find it now. We're at 5.04 oz total weight with DFW weight of .65 oz on a 5 9/16" wheelbase. It's hard to measure the COM with the rear fenders. Thanks.
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Stan Pope
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Re: Help finding COM chart please

Post by Stan Pope »

davet wrote:I once saw a nice chart on here that listed various wheelbases and their COM location vs DFW weight. Can't find it now. We're at 5.04 oz total weight with DFW weight of .65 oz on a 5 9/16" wheelbase. It's hard to measure the COM with the rear fenders. Thanks.
See Computing CM Location by Weighing the Car.
From your data, it computes CM Loc = 0.72"

Your data:
Wheelbase: 5-9/16 = 5.5625
Total Weight: 5.04
Rear Wheel weight = 5.04 - 0.65 = 4.39
Stan
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Speedster
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Re: Help finding COM chart please

Post by Speedster »

A bit Off Topic but fun for scouts to do. Maximum Velocity's 5197 Balance Stand is a clever design. I've always been able to get the car to balance and stay after I let go. You can then easily measure between the center of the axle head and the top of the balance stand with your calipers or ruler. You should be very close.
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LightninBoy
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Re: Help finding COM chart please

Post by LightninBoy »

Speedster wrote:A bit Off Topic but fun for scouts to do. Maximum Velocity's 5197 Balance Stand is a clever design. I've always been able to get the car to balance and stay after I let go. You can then easily measure between the center of the axle head and the top of the balance stand with your calipers or ruler. You should be very close.
:nod:

Yep. Works even with fenders!
Brian Clark
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Re: Help finding COM chart please

Post by Brian Clark »

There's a free app called pinewood calculator that is good for this kind of help.
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davet
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Re: Help finding COM chart please

Post by davet »

Thanks guys.
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