Can anyone help me calculate the correct approach vectors for a surface that is in an angled bore. The bore angle is 26 degrees to my leveling datum and I am using a tip angle of A60 B180. The surface is not on the cad model so I can't get the vectors that way. I used to know how to do this but it has been since my mm4 days that I last used it.
Help with Vector Calculation
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That is great but I guess I was not clear enough in my post. I am not measuring a circle but a machined step(plane) in the bore that is sitting at a 26 degree angle to my datum surface. I need the normal vectors for the surface that is not on my cad model.
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Vectors can be calculated very easily with any calculator with trig functions.
You just need to understand that the 2D vector is the sine and cosine of the angle. For example, the vectors for 30deg are 0.5 & 0.8660524. The axis with greater movement is assigned the larger vector because that axis must move farther to approach/retract normal to the surface.
HTH
Edit: Craiger only gave you the cosine. You need sine also  0.4383711v2013 MR1, v2015.1
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I couldn't remember if it was sin, cos or cos. I actually got the number you gave me I just didn't want to plug it in my CMM without someone verifying I was correct.
DUH PCDMIS will calculate for you. I just put 26 in for one of the vectors and it calculated the others.
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Originally posted by JamesMannes
TKsigpicHave a homebrew
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Originally posted by CeephDUH PCDMIS will calculate for you. I just put 26 in for one of the vectors and it calculated the others.
Cool  I didn't know that worked. I always rotate to any angle and use 0,0,1 0,1,0 or 1,0,0. Just laziness on my part I guess.sigpic
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Originally posted by CeephThat is great but I guess I was not clear enough in my post. I am not measuring a circle but a machined step(plane) in the bore that is sitting at a 26 degree angle to my datum surface. I need the normal vectors for the surface that is not on my cad model.
I know I'm late to the party but I was off yesterday.
This is what I would do. I would realign to your bore. For example, level the bore to zplus and set the x and y orgins on the bore. Then, your plane's vector will be 0,0,1 and it's location will be 0,0,z. After the plane, recall your previous alignment. This way, if the cylinder is off of location or orientation just a bit you will still get good hits. Also, you can get your probe to take hits .005 or less off of the cylinder wall.
I do this all the time. It works wonderfully!
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