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Old 02-06-2012, 09:15 PM
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Quote:
Originally Posted by 9W Monighan View Post
Man, you're making my gears turn in my head!! I need to find some time soon to start my build. It looks like you're going straight to the wheels without anymore reduction. I'm thinking of using a floating axle with a planetary setup out on the ends.
How much spring is in your leafs? Was watching one of my videos loading Brian's tri-axle and when advancing frames I noticed after every bucket full from my drag ,his truck sunk a little more.
No further reduction beyond the diff, but do have 3:1 reduction at the motor. Using an 85T motor - 5200 RPM at 7.4V. Calculated wheel speed based on prototype max speed of 40 MPH, with my trans in 3rd gear. Since my motor turns twice the speed of the diesel, should be very close across entire speed range, since real truck has 6-spd trans. Springs are 0.028 spring steel with same number and width of leafs as real one: 9 main & 16 helper. Spring rate has not been measured. Also, shocks will have heavy coils in them. Estimated payload is 50 pounds based on dry sand and bed volume. Should not get on helpers until about 15 lbs in bed?!?! Springs on real truck are almost flat and scale at 0.048" thick but I thought that would be too stiff for the model.

A lot of "swag" in these calculations, so we'll just have to see how it all comes out.

Ken
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