Originally Posted by jamesweed  well the od does matter cause your tool is cutting on the circum of the part. bigger the circum the greater the distance for the cutter to travel. 52 degrees on 1.4 cir is not the same as 52 degrees on 1.5 cir.
1.4=4.3982 cir cir/360=.0122 per degree 52*.0122=.6344 travel around cir
1.5=4.7123 cir cir/360=.0130 per degree 52*.0130=.676 " " "
remember that you may program z .340 but cutter travels more than that because its moving around cir on an helix(pitch)
I do understand that a degree feedrate with just c axis is not the same as z and c going together. with both going then your pitch has to be included as well. I think... |
I do realize that a 52 degree arc segment of a 2 inch dia. circle will be greater than the same segment of a one inch dia. circle, as would a 1.001 dia. circle segment. I also realize that the tool isn't just traveling .34 in Z, but also in an arc. Figuring that distance is beyond me.
I've always liked math, and been fairly good at it, but if you've never used something....?
I ran 2 test programs this morning. My part program and one with 4 inches added to the X dimensions. Cycle time was 18 seconds for both. Machine is a Daewoo 200MS. Here are the programs if you'd like to try them.
:2 (PLUS 4 INCH)
N820G54M91 (SPECIAL TOOL)
M35
T0808
G98X4.5Z.05C52.
G1X4.145Z.015F100.M88
Z-.62C0F1500.
G0X4.5
Z.05C112.
G1X4.145Z.015F100.
Z-.62C60.F1500.
G0X4.5
Z.05C172.
G1X4.145Z.015F100.
Z-.62C120.F1500.
G0X4.5
Z.05C232.
G1X4.145Z.015F100.
Z-.62C180.F1500.
G0X4.5
Z.05C292.
G1X4.145Z.015F100.
Z-.62C240.F1500.
G0X4.5
Z.05C352.
G1X4.145Z.015F100.
Z-.62C300.F1500.
G0X4.5M90
G0Z1.
M91
M30
:1 (NORMAL)
N800G54M91 (SPECIAL TOOL)
M35
T0808
G98X.5Z.05C52.
G1X.145Z.015F100.M88
Z-.62C0F1500.
G0X.5
Z.05C112.
G1X.145Z.015F100.
Z-.62C60.F1500.
G0X.5
Z.05C172.
G1X.145Z.015F100.
Z-.62C120.F1500.
G0X.5
Z.05C232.
G1X.145Z.015F100.
Z-.62C180.F1500.
G0X.5
Z.05C292.
G1X.145Z.015F100.
Z-.62C240.F1500.
G0X.5
Z.05C352.
G1X.145Z.015F100.
Z-.62C300.F1500.
G0X.5M90
G0Z1.
M91
M30
%
This is the only job I've every run like this so I am having a hard time visualizing. Plus I am an old dog, and you know what they say about us.
