Post by W Racing on May 23, 2009 23:46:30 GMT -7
It is possible to estimate the COM of a car before building it. Below is an example of a Pure Stocker:
5.049 ounces total weight
Using a Tungsten DISC of 4.2 ounces.
Jewkes Edge Pure Stockers
This leaves 0.336 ounces for wood /paint.
This will show you the weight allowance of the car body.
It is possible to drop down in weight on the disc if you want more wood. Don't add too much more wood
The first column of numbers is simply the weight in ounces of the components.
The second column is the COM of the individual components.
The third column is the weight added to the fronnt wheel because that component is on the car...
Note that the rear wheels and axles add no weight to the front of the car.
Also in this example the disc is centered over the rear axle and also does not add any weight to the front wheel.
Wheelbase of car 4.375
Weight (ounces) COM from rear axle Weight on front wheel
Disc 4.200 0.000 0.000
Wheel FR 0.118 4.375 0.118
Wheel FL 0.118 4.375 0.118
Wheel RR 0.118 0.000 0.000
Wheel RL 0.118 0.000 0.000
Axle FR 0.010 4.375 0.010
Axle FL 0.010 4.375 0.010
Axle RR 0.010 0.000 0.000
Axle RL 0.010 0.000 0.000
Primer 0.000 2.200 0.000
Paint 0.000 2.200 0.000
Clear 0.000 2.200 0.000
Wood 0.336 2.200 0.169
Total 5.049 0.369 0.425
Weight Needed 0.000
By moving the tungsten disc forward so that it is exactly in front of the axle.
Wheelbase of car 4.375
Weight (ounces) COM from rear axle Weight on front wheel
Disc 4.200 0.500 0.480
Wheel FR 0.118 4.375 0.118
Wheel FL 0.118 4.375 0.118
Wheel RR 0.118 0.000 0.000
Wheel RL 0.118 0.000 0.000
Axle FR 0.010 4.375 0.010
Axle FL 0.010 4.375 0.010
Axle RR 0.010 0.000 0.000
Axle RL 0.010 0.000 0.000
Primer 0.000 2.200 0.000
Paint 0.000 2.200 0.000
Clear 0.000 2.200 0.000
Wood 0.336 2.200 0.169
Total 5.049 0.784 0.905
Weight Needed 0.000
I will work on a way that folks can work this out for their own cars.
This is very helpful because you know where to drill the hole for the disc to get the desired COM...
5.049 ounces total weight
Using a Tungsten DISC of 4.2 ounces.
Jewkes Edge Pure Stockers
This leaves 0.336 ounces for wood /paint.
This will show you the weight allowance of the car body.
It is possible to drop down in weight on the disc if you want more wood. Don't add too much more wood
The first column of numbers is simply the weight in ounces of the components.
The second column is the COM of the individual components.
The third column is the weight added to the fronnt wheel because that component is on the car...
Note that the rear wheels and axles add no weight to the front of the car.
Also in this example the disc is centered over the rear axle and also does not add any weight to the front wheel.
Wheelbase of car 4.375
Weight (ounces) COM from rear axle Weight on front wheel
Disc 4.200 0.000 0.000
Wheel FR 0.118 4.375 0.118
Wheel FL 0.118 4.375 0.118
Wheel RR 0.118 0.000 0.000
Wheel RL 0.118 0.000 0.000
Axle FR 0.010 4.375 0.010
Axle FL 0.010 4.375 0.010
Axle RR 0.010 0.000 0.000
Axle RL 0.010 0.000 0.000
Primer 0.000 2.200 0.000
Paint 0.000 2.200 0.000
Clear 0.000 2.200 0.000
Wood 0.336 2.200 0.169
Total 5.049 0.369 0.425
Weight Needed 0.000
By moving the tungsten disc forward so that it is exactly in front of the axle.
Wheelbase of car 4.375
Weight (ounces) COM from rear axle Weight on front wheel
Disc 4.200 0.500 0.480
Wheel FR 0.118 4.375 0.118
Wheel FL 0.118 4.375 0.118
Wheel RR 0.118 0.000 0.000
Wheel RL 0.118 0.000 0.000
Axle FR 0.010 4.375 0.010
Axle FL 0.010 4.375 0.010
Axle RR 0.010 0.000 0.000
Axle RL 0.010 0.000 0.000
Primer 0.000 2.200 0.000
Paint 0.000 2.200 0.000
Clear 0.000 2.200 0.000
Wood 0.336 2.200 0.169
Total 5.049 0.784 0.905
Weight Needed 0.000
I will work on a way that folks can work this out for their own cars.
This is very helpful because you know where to drill the hole for the disc to get the desired COM...