Granite So we made a thing

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Can I ask what the dimensions are? I wanted to do something similar that I could throw in the trunk of my car but I didn't think anything that would fit would be worth doing. Yours seems quite small yet it launches pretty well.
 
So I started with 2 feet x 9 inches for the two 3/4 plywood sides. It's a weird dimension sideways because the 1/8 inch thick ply I had was an odd width. So it ended up being 35 1/2 inches wide. Which seems like a good width that we can hit pretty consistently with the truck.

https://toheriman.github.io/Kicker/

I used this tool to calculate the radius for the curve of the ramp. Unfortunately it's metric and only goes to a single decimal place. We used a radius of 5 feet or 1.5 meters which has the ramp ending at a 30° slope.
 
I read up on kicker Ramps. Everything said the curve is important: the increasing angle towards the end of the ramp is supposed to compress the shocks. A final angle of 30° is for long jumps and 45° or more is for bigger air. Since we're averaging 20 bucks a day in repairs we went for a less aggressive angle.

I can make a how to for drawing a curve. Once you make one side you can use it as a template for the other.

Another easy way would be to draw the final angle and then just free hand the curve.
 
So....

2 feet long, 3 feet wide and 9 inches high

Thanks, that's pretty much what I guessed it would be. I want something for my 10 year old son to practice not being on the throttle when landing with, so I'll shoot for 25 degrees launch angle. It looks like the curve calculator you provided uses a fixed radius on the curve. I may try a spiral curve instead.
 
Um. Science! Spiral curve??
Don't be gunning it when you land? Sounds like good advice! We're just learning that braking predictably brings the nose down drastically and ends with disastrous results.

What's this spiral curve ness?
 
You don't want to be on the throttle when you land. The drive train won't like it.

A spiral curve is a curve that starts with an infinite radius and then the radius get progressively smaller as you move along the curve. Spiral curves are commonly used to transition from a straight section to a section with a fixed radius. You'll get a more gradual compression of the suspension on a spiral curve than you will on a fixed radius. The math is a lot harder though.
 
Sooo m m spur gear explode again. Probably because our slip clutch doesn't slip anyway who cares. Gotta buy another spur gear. Maybe I should get the whole assembly so I have the springs and that. Gonna go a couple teeth up on the pinion. Vroom vroom
 
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