Project 1 from EmptyNester. Category: Custom Shop Tools - CNC Table

[Rambozo]

Did you fix SheetCAM so the corners are not still at 200 ipm?

[EmptyNester]

Beats me.

I thought I was cutting at 10 ipm, which seemed slow.

I'm not sure where the speed is in the G-code:

N0010 (Post processor: MP1000-THC.scpost)
N0020 (Date: 10/10/2012)
N0030 G20 (Units: Inches)
N0040 G53 G90 G40
N0050 F1
N0060 (Part: SquareStar)
N0070 (Process: Set variable switchoffset = 0.2)
N0080 (Process: Outside Offset, Layer 2, T1: Plasma - outside profile)
N0090 M06 T1 F10 (Plasma - outside profile)
N0100 G00 Z2.0000
N0110 X2.3082 Y-0.1319
N0120 Z0.5000
N0130 G28.1 Z0.12
N0140 G92 Z0.0
N0150 G00 Z0.2000
N0160 G92 Z0.0
N0170 G00 Z0.5000
N0180 M03
N0190 G04 P0.3
N0200 G01 Z0.0800 F20.0
N0210 G02 X2.2058 Y-0.0295 I0.0000 J0.1024 F10.0
N0220 G01 Y0.0000
N0230 Y2.0075
N0240 Y2.1404
N0250 X2.3091 Y2.0371
N0260 X2.1762
N0270 X0.0000
N0280 X-0.1329
N0290 X-0.0295 Y2.1404
N0300 Y2.0075
N0310 Y0.0000
N0320 Y-0.1329
N0330 X-0.1329 Y-0.0295
N0340 X0.0000
N0350 X2.1762
N0360 X2.2058
N0370 G02 X2.3082 Y-0.1319 I0.0000 J-0.1024
N0380 M05
N0390 G04 P0.5
N0400 G00 Z2.0000
N0410 X0.0000 Y0.0000
N0420 M05 M30

[Rambozo]

Beats me.

I thought I was cutting at 10 ipm, which seemed slow.

I'm not sure where the speed is in the G-code:

N0010 (Post processor: MP1000-THC.scpost)
N0020 (Date: 10/10/2012)
N0030 G20 (Units: Inches)
N0040 G53 G90 G40
N0050 F1
N0060 (Part: SquareStar)
N0070 (Process: Set variable switchoffset = 0.2)
N0080 (Process: Outside Offset, Layer 2, T1: Plasma - outside profile)
N0090 M06 T1 F10 (Plasma - outside profile)
N0100 G00 Z2.0000
N0110 X2.3082 Y-0.1319
N0120 Z0.5000
N0130 G28.1 Z0.12
N0140 G92 Z0.0
N0150 G00 Z0.2000
N0160 G92 Z0.0
N0170 G00 Z0.5000
N0180 M03
N0190 G04 P0.3
N0200 G01 Z0.0800 F20.0
N0210 G02 X2.2058 Y-0.0295 I0.0000 J0.1024 F10.0
N0220 G01 Y0.0000
N0230 Y2.0075
N0240 Y2.1404
N0250 X2.3091 Y2.0371
N0260 X2.1762
N0270 X0.0000
N0280 X-0.1329
N0290 X-0.0295 Y2.1404
N0300 Y2.0075
N0310 Y0.0000
N0320 Y-0.1329
N0330 X-0.1329 Y-0.0295
N0340 X0.0000
N0350 X2.1762
N0360 X2.2058
N0370 G02 X2.3082 Y-0.1319 I0.0000 J-0.1024
N0380 M05
N0390 G04 P0.5
N0400 G00 Z2.0000
N0410 X0.0000 Y0.0000
N0420 M05 M30

Looks like the Z move from pierce to cut height is at 20 then everything else is at 10. F stands for Feedrate and stays active until a change. It can be appended to a motion command but takes effect before that move. I bet 10 is kinda slow for that cut.

[EmptyNester]

Thanks all.

I tried the cut as the last thing for the night. I hadn't realized but the saved Mach config had the THC off. I realized when it was giving constant torch up commands. I guess the torch could have pushed it, but it was a 2 by 4 piece of 16 gauge so I didn't think the torch would be able to push it that much.

I haven't had a chance to try again yet. I was trying to figure out how to spring load a pen. I'll have to see if I can piece something together likes your setup Jester.

I drew the original image in Corel and exported to DXF. It looked fine in sheetcam and in the Mach window, but I wasn't paying close attention.

The distortion seemed odd because it appeared random.

I didn't get a chance to do anything tonight. Hopefully I'll get a chance tomorrow night.

BTW - when I put a new electrode and tip on, the quality of cut really improved.

[sportbike]

It looks to me like something is up with the travel to step ratios. I'd try cutting a series of concentric circles with a consistent increment in diameter increase. Then see if each circle is in fact round and be sure the thickness remaining is consistent and accurate.

Did the plot in sheetcam or whatever you are using look ok?

[Rambozo]

It looks to me like something is up with the travel to step ratios.

Except that would also effect the outside cut.