What angle do I need to cut?

SkyHog

SkyHog

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I suck at math (as I have said thousands of times here).

I want to cut the end of a 2x4 so that when placed flat, it will provide a 1 foot rise over a 3 foot run. Am I right in assuming that is 1/3 or 33.3 degrees to cut the board?


Code: 
Crude drawing:
    ___ (3 ft. Run)
  /    /
 /    /    (1 ft rise)
/____/
 
18.4 degrees

arctan(1/3)

Chief Sohcahtoa weeps.

But why not just measure on the board a 3:1 triangle?
 
Last edited:
Actually...let's do it this way. I have a ramp door, but my racecar bottoms out because the angle is too steep. My plan is to built a small extension to reduce the angle.

Is there a mathematical way to establish what angle I should make the extension so that it will remain consistent and won't bottom out?
 
14 degrees.

Us the tan-1(rise/run) function on your calculator.

And yes, there is. It's called the break(over) angle and depends on wheelbase and clearance.
 
EdFred said:
14 degrees.

Us the tan-1(rise/run) function on your calculator.

And yes, there is. It's called the break(over) angle and depends on wheelbase and clearance.
Click to expand...

Wheelbase is 57" (+/- 1/2") and clearance is 4" at the lowest point....how do I calculate it...
 
Looks to be about 8 degrees.

Your rise/run ratio on the ramp need to be less than 4/half the wheelbase.

Or less that approx 1/7. So build a ramp that's 1:8 and you should be good.
 
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EdFred said:
Looks to be about 8 degrees.

Your rise/run ratio on the ramp need to be less than 4/half the wheelbase.

Or less that approx 1/7.
Click to expand...

c91d2f850ff39c40c56848ef4572eb0c.png


...I'm being daft. 4/half the wheelbase would be what, 4/29?

That's the same as 1 foot over 8 ft right?

Edit: which is exactly what you said in the post I quoted....I am really daft. Lol.

So now I need to measure how long the existing ramp door is, then measure how far from the ground it is, get the rise over run and I should be able to make my extension as needed....
 
Or, just take your car, put the middle of the wheelbase where the ramp meets the floor, and lower the ramp until it bottoms out.
 
If I understand what all have said, that would be minimum. Ie the buggy will scrape slightly. Allow extra.
Ignore if already covered.
 
It is currently 2' over 6.5'....is there a formula for what I need to build to make that 1 over 8?

Edit: reduced the height to 2 ft as I forgot that I did not have the hauler level when I measured.
 
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SkyHog said:
It is currently 2' over 6.5'....is there a formula for what I need to build to make that 1 over 8?

Edit: reduced the height to 2 ft as I forgot that I did not have the hauler level when I measured.
Click to expand...

Really? 2/x = 1/8. Come on, man!
 
SkyHog said:
Are you saying I need to build an extension 16ft long?

Edit: remember, I'm mathematically retarded.
Click to expand...

No, he is saying that you need to break the trailer tongue to lower the height and solve the problem with minor modification of the current ramps.

Actually, he didn't say that but a 16' ramp is absurd.
 
I called Nick and gave him a no need to measure solution.
 
Ive always been a measure up y" put a mark, measure over x" put a mark, and then draw a line between the two kinda guy but keep doing math y'all.
 
I'm sitting here wondering why he didn't just put a racing jack under the front of the trailer. There's one right there in the back with the car anyway, right? ;)
 
Seanaldinho said:
Ive always been a measure up y" put a mark, measure over x" put a mark, and then draw a line between the two kinda guy but keep doing math y'all.
Click to expand...

I've been places ya can't do that. Piping layout can get interesting in an industrial environment.
 
SkyHog said:
I suck at math (as I have said thousands of times here).

I want to cut the end of a 2x4 so that when placed flat, it will provide a 1 foot rise over a 3 foot run. Am I right in assuming that is 1/3 or 33.3 degrees to cut the board?


Code: 
Crude drawing:
    ___ (3 ft. Run)
  /    /
 /    /    (1 ft rise)
/____/
Click to expand...

Learn to use a carpenter's square. Run/rise is built in and you don't have to do any math.
 
SkyHog said:
Actually...let's do it this way. I have a ramp door, but my racecar bottoms out because the angle is too steep. My plan is to built a small extension to reduce the angle.

Is there a mathematical way to establish what angle I should make the extension so that it will remain consistent and won't bottom out?
Click to expand...

ROT for trailer ramps, 8 times the height of the deck for a street legal clearance will keep you from high centering, sometimes you have to pick up the nose of the trailer for low cars. That's why you see lift gates on most race car trailers. Your track car should be fine with 8:1.
 
If you want to invest in some good electric trailer jacks, there is an elegant solution that will also be beneficial if you start getting into lower toys. With jacks you can lower the hinge point by raising the nose thereby reducing the angle, pull onto the ramp, lower the nose so the ramp and deck are straight, winch the car up, then lower the nose.
 
If all else fails, you can do like we do on the farm.

Find an incline or a ditch and back up to it. ;)
 
txflyer said:
If all else fails, you can do like we do on the farm.

Find an incline or a ditch and back up to it. ;)
Click to expand...

That's how I did it with my old trailer. Being 30 feet long, I don't know that I could easily find an incline that provides enough room for my tow truck and the hauler within the pit area.

I'm probably just going to jack the front end of the trailer up as much as I can to reduce the angle, then build a smaller extension if that is still not enough. The bad part of having such a large trailer is that it sits quite a bit off the ground, and it was clearly designed to be loaded with ATVs, which have huge ground clearance.
 
SkyHog said:
That's how I did it with my old trailer. Being 30 feet long, I don't know that I could easily find an incline that provides enough room for my tow truck and the hauler within the pit area.

I'm probably just going to jack the front end of the trailer up as much as I can to reduce the angle, then build a smaller extension if that is still not enough. The bad part of having such a large trailer is that it sits quite a bit off the ground, and it was clearly designed to be loaded with ATVs, which have huge ground clearance.
Click to expand...


I doubt if you can do it on your application, and I don't know how to build them, but I know an arched ramp offers much more strength and drive on/off loading clearance than flat if you can figure one out. :redface:
 
SkyHog said:
That's how I did it with my old trailer. Being 30 feet long, I don't know that I could easily find an incline that provides enough room for my tow truck and the hauler within the pit area.

I'm probably just going to jack the front end of the trailer up as much as I can to reduce the angle, then build a smaller extension if that is still not enough. The bad part of having such a large trailer is that it sits quite a bit off the ground, and it was clearly designed to be loaded with ATVs, which have huge ground clearance.
Click to expand...

You can lower the suspension on your trailer if you don't need all the ground clearance.
 
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