Programming a radius

[fukeneh]

I am learning more and more about programming but I am still having problems with programming a radius. Can anyone explain the best way to program a radius on a lathe and how you come up with the numbers used. I know the tool nose radius effects the way you program it, but what I am looking for is a better understanding of how to program a radius on a lathe. And how you get each number for the radius.

Thanks

[CNCRim]

The best way to understand it is try to understand the right triangle, and trigeometry....... then it will work for almost every radius you want to program.

[theemudracer]

Here is an example of programing a 45 degree chamfer with .040 radius on the corners of the chamfer.


(CHAMFER)
G50S2500
T1010
G0G96S800M3
Z0M8
X1.35
G1X-.04F.01
G0W.05X1.0369
G42G1Z0F.006
G3X1.0934Z-.0117R.04
G1X1.2266Z-.0783
G3X1.25Z-.1066R.04
G1G40X1.35
G28U0
G97M01




Here is an example with just a .125 radius

(CHAMFER)
G50S2500
T1010
G0G96S800M3
Z0M8
X1.35
G1X-.04F.01
G0W.05X.8
G42G1X1.Z0F.006 (THE X START POINT IS = END POINT-(RADIUS*2)
G3X1.25Z-.125R.125 (THE Z AND R WILL ALWAYS MATCH IF IT IS A 90 DEGREE RADIUS FROM Z0.)
G1G40X1.45Z-.2
G28U0
G97M01

[Geof]

Are these any help?

http://technology.calumet.purdue.edu.../lecture13.pdf

http://technology.calumet.purdue.edu.../lecture17.pdf

[fukeneh]

Wow thanks guys. That was a great read. If you have any other guides like that could you post them too. i.e. threads and such. They makes some good reference reading.

[Geof]

Originally Posted by fukeneh Wow thanks guys. That was a great read. If you have any other guides like that could you post them too. i.e. threads and such. They makes some good reference reading.

The two links I gave are /lecture13.pdf and /lecture17.pdf but there are a total of ten lectures numbered 10 through 20. Just open one in Adobe and then go through the whole lot by changing the number. You can also save copies of course.

[oldjohn]

newtexas2006 neans trigonometry.
Have a look:

[Andre' B]

Originally Posted by Geof The two links I gave are /lecture13.pdf and /lecture17.pdf but there are a total of ten lectures numbered 10 through 20. Just open one in Adobe and then go through the whole lot by changing the number. You can also save copies of course.

Top level link to the course, there is more there then the PDFs.
http://technology.calumet.purdue.edu/met/mfet/275/

[tobyaxis]

Originally Posted by fukeneh I am learning more and more about programming but I am still having problems with programming a radius. Can anyone explain the best way to program a radius on a lathe and how you come up with the numbers used. I know the tool nose radius effects the way you program it, but what I am looking for is a better understanding of how to program a radius on a lathe. And how you get each number for the radius. Thanks

Have you considered a CAD CAM Software like BobCAD-CAM??? It will make programming arcs and angles fast and simple with zero mistakes. Trig is a valuable tool, but mistakes are costly.

V2007 doesn't have a Lathe Module yet but V21 does. It is a great tool for Programming Complex Geometries.