# Need help with a calculation

Discussion in 'The Lounge' started by sled_dog, Feb 23, 2004.

1. ### sled_dog1 ton status

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Alright I located my rear under the buggy and I want to figure out what angle my lower links are at. I did some math and found that from the axle end of the link to the frame mount is a 1" rise. This takes place over 31.5". So can I take those numbers and figure out the angle of them? I asked my dad the master carpenter and he didn't freaking know /forums/images/graemlins/rotfl.gif said he always uses a "345" square so doesn't have to know it.

2. ### wraenking1/2 ton status

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i dont know if that will give you and angle. it will more give you a slope percentage.

%slope vdx x 100
_________
HD

vd = verdical difference

HD is your distance.

wait for an expert to reply though

3. ### Resurrection_Joe1 ton status

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Yeah you can do it, I forget how though, simple trig

Your links rise and inch over 31.5"? I have no idea, but that doesn't sound right, maybe I'm just too ignorant of linked suspension

Damn it..... trying to remeber triginometry

Uh, from my ass math, I think 1.8*

31.5" as the radius of a circle

63" Diameter

197.82" Circumference

49.455" Through 90*

1.82* for every inch of travel through the 90*

Orrr uhhh yeahhhh

I realize this method gets way more off as the inch in question gets bigger, but I figure it's around 2*

4. ### sled_dog1 ton status

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probably more like 18*. What doesn't sound right about it? The goal is the lower link as close to parrellel with the ground as I can get it.

5. ### 84k51/2 ton status

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(sin) old hippies (cos) are high (tan) on acid

sin (theta) = opposite/hypotenuse
cos (theta) = adjacent/hypotenuse
tan (theta) = opposite/adjacent

Fell asleep in the sixth grade huh? /forums/images/graemlins/whistling.gif

6. ### Resurrection_Joe1 ton status

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Like I said dude, I have NOOOOO idea about linked suspensions, if the links are supposed to be flat as possible, I'll go with that

7. ### sled_dog1 ton status

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shut my mind off a few years ago. Been too long since Geometry.

8. ### Stickseler3/4 ton status

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1.82 DEG or 88.18 DEG off level

Tell your dad to buy a Construction Master Pro /forums/images/graemlins/tongue.gif

9. ### 84k51/2 ton status

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Joe's got it right, that's just the hard way. Use the inverse tangent function on 1/31.5

10. ### sled_dog1 ton status

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I'm no genius of this stuff, guys around here know a lot more than me. I just tried to get a little angle on the lower links, 10" distance between the upper and lowers, and half that at the other end. 45* angle on the upper links to control side to side.

11. ### Resurrection_Joe1 ton status

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I WIN I WIN I WIN

This is like the time I went on a field trip to the dam in Pierre SD. I identified thier air compressors as old WW2 airplane engines, and I felt smart, but no prize, I said "Where's my dam prize?", get it? They didn't have a souvenier shop......

12. ### justinf1/2 ton status

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You are looking for the angle relative to the ground correct? If so, take the inverse sine of (1/31.5). Which gives you an angle of 1.82 degrees.

13. ### sled_dog1 ton status

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inverse tangent, inverse sine, which is it?

14. ### sled_dog1 ton status

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ok 1/31.5(sin) and (tangent) both work out to 5.5*.

15. ### 84k51/2 ton status

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Tangent. It would be sine if the link was 31.5" long, not the distance parallel to the ground. The answer is almost the same because the angle is so small.

16. ### sled_dog1 ton status

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hmm looking at the pictures it does look more like 1.8*. My back is up against the fence of my dogs cage so I can't look any better.

17. ### 84k51/2 ton status

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Inverse tangent. It is 1.818302964

18. ### justinf1/2 ton status

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You're right, I looked at it and figured 31.5" was the length of the link. When you plug it in, it should give you 1.82 degrees, not 5.5 degrees. Like 84k5 said, with such a small rise over that distance, it doesn't affect it very much.

19. ### sled_dog1 ton status

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inverse tangent, hmmm how do I do that?

20. ### justinf1/2 ton status

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Look at your calculator, most scientific ones have a shift key with additional functions listed above the keys. Usually, inverse tangent is listed above the tangent key. and is labelled tangent raised to the minus one power. (tan-1)