4th axis programming question

[Delw]

Lets say I want to plunge a 3/8" endmill down in th "Z" at y0.0 and not move the "Y" axis but make a 45º angled cut-out line in a round tube .( reason being this would keep the cut out edges 90º to the tube itself)

would I move the "X" axis to where the end of the "X" axis is on that line and the "A" axis the ANGLE of the line at the same time or would I move the "A" axis the LENGTH of the line with a g18 or something.


for example

G00 X0 Y0 Z0
G1 Z-0.250 F15.0
G1 X1.250 A45.0 F35.0
G00 Z0.5


Does the HAAS reconize only angles on the 4th axis or lenths or both with different g codes? is there a code to make it reconize the lenths.
On a full 4th axis does the feed rate on the A axis work the same like the X Y or Z axis, I guess what I am trying to ask is if there synced?

Just trying to figure this 4th axis out before I start writing a code generator/post.

Thanks
Delw

[Ydna]

Well, in answer to your question yes you would need to just specify the X and A, leave the part at Y0.0, and it'll cut a helical slot like you want. The control will act linear so long as you use a G1. There's a setting in the control where you can enter diameter and it calculates the rotational feedrate. You can also use G93 (inverse time feed) which specifies how long it'll take to reach the next point depending on your RPM, but you'd have to do the math yourself for that to work.

There is also the ability to perform a cartesian-to-polar conversion, which will take your XY program and wrap it around a pre-defined diameter, substituting the A axis for the Y. I haven't used that on the control though so I'll let somebody else explain that.