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Camcalc never worked?

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stevehuckss396:
Hey my apologies! It does work I was just looking at it the wrong way. I layed out every cut in cad and it was spot on! Please ignore my next 3 posts!

Jasonb:
The way I understood it Camcalc uses trig to allow for the angular offest of where it is cutting as well as the vertical and the cuts are all tangent to the profile as shown in green. Rod (Tangler) who wrote it is a member here so if he does not see  your post why not PM him

At 39deg the cut will not be directly above the axis of rotation so will not be at 90deg to your black line

Scroll down to the second illustration of the latest version and you will see the blue (cut) lines are all tangent to the cam . The right angle formed by the angle of the vertical angle of the cam and the horizontal cut does not intersect on the cam profile as you have it shown on your first image but cuts it as your second images outer line

https://www.dropbox.com/home?preview=cam+with+draw.xls

Your ball nose cutter may be the problem as it may not be getting moved sideways enough to produce the profile which is based on using a flat ended cutter that will move either side of the axis. If using a ball nose cutter you will nee dto calculate Y movements as well as Camcalc's Z movements assuming X is the cut direction

If you look down the Camcalc heights it should show more than 0.208 for 39degrees

Jasonb:
here it is done a bit neater in Alibre using the Hoglet cam as an example.

at 39deg Camcalc will give 0.191" which will result it it cutting tangent to whatever part of the cam is at the highest point and offset some distance in Y. It does not give 0.178" at 39deg so no chance of it lopping off the top of the lobe.

If you are not moving your ball nose cutter in Y there there is a risk that the rising cam will hit the cutter if it is stationary above the axis of rotation.

Jasonb:
The other thing to remember is that Camcalc's angles start from when the flank starts to rise above the base circle so will be offset from the high point of the cam by approx half the cam duration angle

Taking the Hoglet cam image I posted above the 0.191" is 0.023" above the base radius of 0.168"

Looking down the chart produced by Camcalc you can see that the height of 0.023" corresponds to an angle of 29degrees and the high point of the cam is cut at 68degrees. Difference between 29deg and 68deg is the 39deg position of the cam that you chose to draw your line at.

stevehuckss396:
Hey my apologies! It does work I was just looking at it the wrong way. I layed out every cut in cad and it was spot on! Please ignore my next 3 posts!

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