Sherline Mini CNC Lathe

[Glen]

[size=12pt]Hello Dalee,
Well I tried the gcode you wrote and I got this on the first line (Unknown word where unary operation could be on line 1. Here is a pic of the mandrel that goes into my lathe and the finished piece. hope this will help
Glen

 

[Glen]

[size=12pt]Hi Dalee,
No sir, no tools in the quick tool change for sure, and I also slowed the speed down too F3 to watch everything also. I have made that mistake once before,
that wont happen again. Had to buy a new mandrel. Well I will try the changing like you said and let you know what happens.. Thanks again for the help.
Glen[/size]

 

[Glen]

OK Dalee,
I went and did what we talked about I had to change the G92 to G92.2 then it worked fine. but I do have a question about one line in the file.
Line N30, This runs the tool in then back out ? I don't understand is there a reason for this, just curious.

N10 G0G40G99G92Xx.xZx.x
N20 T1 (calling for tool #1 and it's predetermined offsets)
N30 X.130Z0 (Rapid to .100" above part G0 is modal and runs until changed by another command like G1)
N40 G1 X.03 F10 (G1 is modal and continues until changed by another command like G0 Feed of 10" per minute)
N50 Z-2.45 (Feed to length on Z axis)
N60 X.02 (feed out to clear X axis)
N70 G0Z0.0 (rapid back to start point)
N80 G1X.06 F10 (Feed into the next cut at 10ipm)
N90 Z-2.45 (feed to length)
N100 x.02 (Feed out from part)
N110 G0Z0.0 (Rapid aback to start)

Repeat Ad Nausium until final dimension is reached.

To end your program, I would use these lines.

NXXX G28 (return to Program offset)
NXXX G40G92.2 (Cancel all tool comps and cancel the G92 offset as stolen from the DeskCNC manual)
NXXX M30 (End Program)

 

[Glen]

[size=12pt]Hello Dalee,
Well I finished the code and ran it (cutting air) ;D.
Take a look and tell me what you think.[/size]

[size=14pt]N10 G0G40G99G92.2X0.0Z0.0
N20 T1
N30 X-.13Z0
N40 G1 X.03 F10
N50 Z-2.45
N60 X.02
N70 G0Z0.0
N80 G1X.06 F10
N90 Z-2.45
N100 x.02
N110 G0Z0.0
N120 G1 X.09 F10
N130 Z-2.45
N140 X.02
N150 G0Z0.0
N160 G1X.120 F10
N170 Z-2.45
N180 x.02
N190 G0Z0.0
N200 G1 X.150 F10
N210 Z-2.45
N220 X.02
N230 G0Z0.0
N240 G1X.180 F10
N250 Z-2.45
N260 x.02
N270 G0Z0.0
N280 G1 X.210 F10
N290 Z-2.45
N300 X.02
N310 G0Z0.0
N320 G1X.240 F10
N330 Z-2.45
N340 x.02
N350 G0Z0.0
N360 G1 X.270 F10
N370 Z-2.45
N380 X.02
N390 G0Z0.0
N400 G1X.300 F10
N410 Z-2.45
N420 x.02
N430 G0Z0.0
N440 G1 X.330 F10
N450 Z-2.45
N460 X.02
N470 G0Z0.0
N480 G1X.360 F10
N490 Z-2.45
N500 x.02
N510 G0Z0.0
N520 G1 X.390 F10
N530 Z-2.45
N540 X.02
N560 G0Z0.0
N570 G1X.420 F10
N580 Z-2.45
N590 x.02
N600 G0Z0.0
N610 G1 X.450 F10
N620 Z-2.45
N630 X.02
N640 G0Z0.0
N650 G1X.480 F10
N660 Z-2.45
N670 x.02
N680 G0Z0.0
N690 G1 X.510 F10
N700 Z-2.45
N710 X.02
N720 G0Z0.0
N730 G1X.540 F10
N740 Z-2.45
N750 x.02
N760 G0Z0.0
N770 G1 X.570 F10
N780 Z-2.45
N790 X.02
N800 G0Z0.0
N810 G1X.600 F10
N820 Z-2.45
N830 x.02
N840 G0Z0.0
N850 G1 X.6490 F10
N860 Z-2.45
N870 X.02
N880 G0Z0.0
N890 G28
N900 G40G92.2
N810 M30[/size]
[size=12pt]Thank God for copy and paste [/size]

 

[Glen]

[size=14pt]Hello,

yeah its a blast, ;D

Well for as the rapid over it don't. Where I touch the end corner of the piece
it rapids out then goes to the starting point of the cuts.
After the program finishes the cuts, it does go back to the starting point
to start a new piece.

Now for as line N30 goes, I really don't start from the center of the piece,
because the rod that goes through the piece and the tailstock live center butts
into the center of the rod. So I start at the corner edge to start my cut.

Glen [/size]

 

[Glen]

Hey dalee,

Well got some info on the lathe. Here it is..

[attachimg=1]

Sherline lathe setup:



Basic operating coordinates for a lathe are shown above.

The X movement moves the cross slide in and out. The commanded position is in diameter.

Moving to X=1,

G1 X1 F10

Will place the tool tip at a position that will cut a 1" diameter part. This is 1/2 inch from the centerline of the spindle rotation.

The Z coordinates control the saddle movement left and right. Set the Z=0 position at the front of your part. All plus movement is away from the part, and all minus movement is inside the Z area of the part.

Setting tools:

In the picture above the part in the chuck is .5 inch diameter. If the tool is jogged until it just touches the OD of the part, it will be at 1/2 inch ( .500). To do this without breaking the tool. or marring the part, place a slip of paper between the part and the tool tip. Jog in toward the part until the paper is squeezed between the two and won't move. If you use the incremental jog set to .001 inch, the paper will be held at a very repeatable position.

In DeskCNC, once the tool tip is in position in X, from the menu select Controller-Set Coordinates, and enter the diameter of the part ( .500) in the X box and click the Set button.

Click Exit to close the Set Coordinates dialog.

Now jog over to the front of the part, and again jog in small increments until a piece of paper is held between the tool tip and the front of the part.

From the DeskCNC Controlelr menu select Controller-Set Coordinates, and enter 0 for the Z value. You can also click the Z-Zero button above the digital readout area to zero the Z value.

Any jogging from this point on will display the machine position that will be cut on the part. you can manually jog the tool tip and face the part, or turn a diameter.

In Vector Cad-Cam, the Desklathe post processor will provide a translation of lines and arcs drawn in Vector into the G-code required to cut whatever part is drawn in Vector into the commands to make the part in DeskCNC. These command are G-codes.

 

[Tony Wells]

That seems a little odd to me. I've only done a little programming, but home is far away from spindle center and chuck face on the lathes I have worked with. Tools are qualified off the OD and face, and the absolute distance from home is used to determine where to start the cut, often 0.1000 off the face when turning. This is often just programmers preference. Some like to rapid much closer to the part.

 

[Tony Wells]

It's probably just differences in terminology and what we were taught. It's been a while for me, so perhaps I'm just not remembering correctly. Our machines always went home to change tools, and the tool position was X:Z in negative integer expressions referenced from home.

At least, that's the way I remember it.

 

[Glen]

No I hadn't since we rewritten the code. I'm still waiting to get it right before any at temps, don't want have to buy another mandrel again> after the first mandrel looking like a bow, i learned my leason, cut plenty of air first.

Glen

 

[Glen]

Ok,
Here is a link to my video on youtube, [video=youtube;9B_g5IdlUY8] http://www.youtube.com/watch?v=9B_g5IdlUY8 [/video] Check it out and tell me what think.
This is the code we was working on.

Glen