need Bridgeport discovery DX32 programming help

[dfelice]

I don't understand why this program won't run.

I always get "parser: bad arc radius or endpoint" on line 45.

N5 G70 G75 G90 G17
N10 G0 X0 Y0 T07 M6
N15 S1783 M3
N20 M8
N25 G0 X2.9380 Y-1.0000
N30 Z.1000
N35 Z-.1000
N40 G1 X3.1880 F8.0
N45 G3 X3.1880 Y-1.0000 R-.2500

this is not actually the end of the program, but the line it always fails on. The tool dia. is set to zero

Any help is appreciated.

[machintek]

I am not a programmer but check your programming manual. I do not believe that a radius can be negative.
I am assuming that you are trying to move 360 degrees.
Try a G79. Look it up.

George

[dfelice]

thanks, I removed the negative from the radius, and it did not help.

Your right about the G79, it is a circular bore. My problem is this program was posted by Espirit. It has happened to me a few times now, and I want to figure it out so I can either change the post processor or whatever setting in the mill is causing the error.

[dfelice]

OK, I realized for a 360° circle it needs to be programmed different. The programming manual states, "to program an arc of 360°, either the x,y, or z endpoint must be programmed together with the arc center". Unfortunately it does not give an example. So, I changed line 45 to read

N45 X2.9380 Y-1.0000 I3.1880 J-1.0000 R.2500

It still didn't work, but rather than error out, it moved from the arc center to the arc endpoint at the programmed feedrate and then rapid traveled back to the arc center.

I then tried

N45 X3.1880 Y-1.0000 I2.9380 J-1.0000 R.2500

This failed immediately.

Now that I know the programming must be different I know I'll need to edit the post processor, but to what. I couldn't seem to make it work using what the programming manual told me and manually entering the commands. I didn't spend to much time on it, it was 8pm on Sunday evening, so I quit for the day.

Anyone have any suggestions?

[dfelice]

thanks,

[CNCRim]

I think it's better you should change your post processor so it output I and J, it's better that way. I know some machine won't take radius more than 180deg, therefore you must break circle in two quadrant(N40 G1 X3.1880 F8.0
N45 G3 X3.6880 Y-1.0000 R.2500, X3.1880 Y-1.0000 R.2500). Change you post!!!!!

[gdwood3rd]

For older Hardinge/B'Port Iron, Go to Solverstechline.com. They are former H/B'Port employees with the 411 to help you out.

[dfelice]

I tried changing the X,Y to I,J it did not operate correctly. It acted as if it were trying to cut a circle 3.188 inch radius and start at 180° in the circle rather than starting at 0°.

thanks for your suggestions.

[machintek]

A long time ago I used EZCAM on a MAC and I would draw a small circle tangent at the top to the large circle. I would create points at the 45 degrees on the smaller circle and at 0 and 180 on the large circle. Thus I would start my cut on the smaller circle at 45 degrees, arc in to the tangent point at 0 degrees, continue on the larger circle to 180 degrees, continue to the 0 degree tangent and continue to the -45 degrees on the smaller circle.
Thus it would arc in, mill my circle and arc out. I would have a minimum dwell mark on my circle and it was the most reliable way of getting the EZCAM to do what I wanted it to do. It did post with I J. I believe most post processors do.

George