Need some help learning TahlCam

[Holmes_ca]

Hello Bill and Gerry, its me again, Edmund,
I have reached the stage,......... of drawing a part in autocad and changing it to a DXF file, now I have a image of cutter in cutviewer that travels to a point on the part and travels around the outside returning to the start,trouble now is I have a lot of squigly lines at the start and end of run and when cutter reaches the end of cut, the cutter does a lot of loops and circles and winds up cutting into the part, I have tried to trim the squigly lines but am unable to, so I try a erase but that erases all the drawing, can you give me some suggestions?,
Oh yes, I loaded a .250 cutter and got a window informing me the radius was 3 times smaller than the cutter radius so I entered a smaller cutter and still get the message but its only 1 rad now, I believe the squigly lines evolved from that problem,

[wjbzone]

Hello Edmund,
Just getting back from the Thanksgiving holiday. Hope everyone enjoyed the week as much as I did.
I don't have cutviewer, so cannot comment on the results there.
I review my paths inside Autocad/Tahlcam. Are you seeing the same results there as you do with cutviewer?

Could be some problems with the start and end of the path. The corner radius smaller then (or same as) the cutter radius has caused some problems in past. Have you tried a square corner on the path (or test with an even smaller cutter).

I could take a look at the drawing if you want to send or post.
Bill

[Holmes_ca]

Bill, welcome back, Ive missed yah, big grin,

No bill, what I meant by cutviewer was the cutviewer in the Tahlcam program, although I do have the other cutviewer, I purchased that one with Meshcam,
I think whats happened at this point is I went into pathwork and pathfinder also pathdirection, then leadin, and I think thats where my problems started, (the squigly lines) at start and finish of run,
Hope you can understand, I will try to send drawing, not sure exactly how, here goes,

[wjbzone]

Edmond,
The file transfer worked fine. No need to use .dxf, just send the .dwg file.

I looked at your drawing and see the lead in and lead out are a problem. I got it to work by:
1. Deleted the set of curves on the lead in.
2. Extended the horizontal line you are starting on so that it does not connect to the end curve. (Not necessary, but its easier to pick the start point for pathfinder)
3. Click Pathfinder, type an F, enter 0.01 fuzz. (some of your lines are not connecting)
4. After Pathfinder creates the polyline from your lines, I used Leadin to create a lead in and lead out.
5. Select a 0.250 Ø tool.
6. Run selection. It gives me a warning that radius is smaller then tool, but runs anyway. (The warning occurs if you use a radius exactly the same as the tool, but it still works)
7.Create group (Path1)
8.Clipboard - T02 PATH1
9.Post.

I attached my drawing and the post.

hope this helps
Bill

[wjbzone]

I thought I uploaded both files, didn't seem to work. Heres the post file.

%
O0005()
N10 G90 G00 G90 G40
N20 G49 G80 G17
N30 G20
(CONTROL 1)
(COOLANT=FLOOD)
N40 M09
N50 G91 G28 Z.0000
N60 M01
(TOOL CALL)
N70 T02 M06 (.2500 DIA EM HSS)
N80 S1000 M03 (HFDR 6.0 VFDR 2.0)
N90 G90 G43 D32 H02 Z4.0000
N100 M08
(SKIP-FP PATH1)
N110 Z1.5050
N120 X-.3857 Y-1.1927
N130 Z.3000
N140 G01 Z.0000 F2.0
N150 G41 X-.3494 Y-1.0575 F6.0
N160 G03 X-.4444 Y-1.0450 R.3668 F6.0
N170 G01 X-1.0200 Y-1.0450 Z.0000
N180 Y.0000
N190 G02 X.0000 Y1.0200 R1.0200
N200 G01 X2.1500 Y.8176
N210 X2.1914 Y.8129
N220 G02 X2.9620 Y.0020 R.8120
N230 G01 X2.9620 Y-1.0450
N240 X2.4420
N250 Y-.9200
N260 G03 X2.3170 Y-.7950 R.1250
N270 G01 X.1403 Y-1.0103
N280 G02 X-.3341 Y-.9637 R1.0200
N290 G03 X-.4944 Y-1.0450 R.1250
N300 G01 X-.5044 Y-1.3098
N310 G40 X-.3645 Y-1.3151 F6.0
(JUMPZ)
N320 G00 Z1.5000
(COOLANT=OFF)
(PARK)
N330 M09
N340 M05
N350 G91 G28 Z.0000
N360 G90 X4.0000
N370 G91 G28 Y.0000
N380 M30
%

[wjbzone]

One thing to keep in mind when using Leadin, each time you use it, it adds to the previously created Leadin. You want to redo it, you can use undo to remove previous leadin before doing it again.
Bill

[Holmes_ca]

Hello Bill, thank you for all the time you are spending trying to educate me, OK, heres the problem now, first I was unable to open your autocad drawing, something about not compatable, so I had to use my drawing, I followed your instructions and managed to produce a G-code and post it in a clipboard, the tool starts with a leadin to the left bottom corner of the part, and travels around the outside edge in a clockwise direction perfectly, but as it nears the end of its run, right at the large radius where the tool should travel upwards slightly to the small .250 radius and then travel downwards and then finish in a horizontal direction to the bottom left corner, the tool stops at the bottom of large radius and then shoots over to the finish corner stops and it then reverses back cutting into the part and stopping at the bottom of the large radius, the reverse path is a blue colour, and the clockwise is green,

Sorry to sound like a dunce, but sometimes I have a hard time decifering.

[wjbzone]

Edmond,
What version of Autocad are you using. (I posted Autocad 2004).
Here is the dxf of my drawing. Hope you can open this.

[wjbzone]

Try again, The dxf file I uploaded did not work?

[wjbzone]

Zoom in to the end where the tool starts making those reverse directions. The small radius at the path end needs to be erased.

Explode your path, erase all the leadins and leadouts. Redo the leadin and out. Zoom in to end to be sure what is has done. Then redo the path.

Test the results from the Lead in dialog box to be sure what you get. If you want, you can draw the leadin yourself. (or no leadin at all)

Bill

[Holmes_ca]

Bill, Im sorry but I am stumbling around like a blindman, Ive got drawings and folders all over the place, Im so confused I dont know my arse from my elbow, is it possible we can start right from the beginning, Im really sorry, I tried your latest dxf this morning but Im like clutching at straws

..............................................................

[Holmes_ca]

Hello Bill, I have just done a rectangle drawing in autocad 2000, used polyline, I followed your instructions, pathfinder, fuzz, 0.010, then path direction, then leadin, the toolpath of cutter starts at bottom left corner and leads in, then travels around outside of part and leads out at bottom left corner, I have created path group, in a clipboard, can you tell me how I can view the gcode?,

It seems my troubles occur with the straight lines and radiuses when I combine the two, any thoughts,