Hi, this may be an easy one for you all but I am not sure. So here is the question the end result is sort of a stair step pyramid in the center of a round pocket cut so that the top of the pyramid is the same height as the top edge of the material. I guess another way to describe it is concentric cylinders and to threow anoterh wrench into thing I need to cut all the way through the last cylinder about 1/16 from its edge.

Is there a name for this kind of cut? O r is it simply using bit widths and so on.
I added a picture if my description was not good enough.
If this is not a special kind of cut the mach knows how to do or there is a trick to I would start out as follows

I would start with 5/8 inch stock
mill out the center hole
then step out the width of the edge of that first wall
mill out the remaining parts to this secondary depth the step out again the width of the second step
and then mill out the remaining area to create the third step.

Do you think lazycam may be able towork out the GCODE for the cuts?

You can use wizards or LazyCam to provide the Gcode. Wizards would be easier as LC requires a learning curve.

RICH

What kind of accuracy, and what kind of quantities? aif you make the center of the part 0,0 the code is real simple. I & J would both be 0(zero) for all the cuts. Just a matter of subtracting the cutter radius for the bore and adding the cutter radius for the OD's.I would have teh bottom of the part as Z0 and go from there.

I and J can never be BOTH zero. Unless, of course, you're using the R word to define the radius, and then I and J are not used.

Dan

Moderator edit. Double posting merged

HI I just lost my previous post and I am not sure why so this is going to be short and sweet. I am new to CNC and especially the 3d aspect I have cam programs (lazycam, cambam, meshcam) but just can't seem to get the gist of it I have a part I need to mill out. It is pretty simple (or so I think) but I can't get anywhere on it and I was hoping someone that is in the know could post the correct Gcode and I could use it as a template for a second part I need to mill that is the best way I learn--See a few working examples and then work it out--. Anyway here is the part I will also add an imagewith that and my description I should be able to get the part detailed accurately enough.

3 concentrically centered stacked cylinders

Bottom Cylinder: D 1 1/4" H 3/16"
Middle Cylinder:   D 1"  H 1/16"
Top Cylinder:      D 7/8" H 3/16"

The last detail and probably the first done is to millout a Hole with diameter of 3/4" from the top, centered and through all three layers . Well there it is any help on this is greatly appreciated and any pointers on a good beginner level Gcode tutorial.

I have had exposure to Gcode when my DXF file polylines were converted into what looked like small little lines in Gcode but I saw an arc command and was wondering if using it to make circles is even possible or better..
Any Thanks for any help
Jeff

What tools do you have to hand?

Graham

As stated I am new to CNC so my tools are fairly limited I have 4 endmills 3/16",1/8", 1.5mm, 1.0mm I assume I would probably use the 1/8" for most of the work since the steps are 1/8' wide. I have methods in my head but getting them from my head to Gcode is where the stumbling occurs.

I would mill  out the inner .750 hole at the top using a cut so that the outside edge is at 3/8" from the center that would give me my 3/4" hole.
Next I would mill out the next level so the centerline of the cut is at 7/8" from the center at a depth of 3/16" which would give me the top of the middle cylinder as I described it previously and the OD of the top cylinder.
Next again using the centerline cut but this time at 1 1/8' from the center at a depth of 1/4" which would give me the top of the bottom cylinder and the correct width of the middle cylinder
Lastly to freem the piece I would do one more milling so that the inside edge of the milled area would be 1 1/4" and adepth of 3/16 to get the outside edge of the bottom cylinder with a stock size of 7/16" this should free the piece.

Now this is what is my head and because I am new it may be incorrect and need some revising but at least you can see I am trying. My biggest issue is translating these movements to Gcode
Inside edge cuts, outside edge cuts , centerline cuts, I am not sure how this translates to Gcode, I assume you through some offsetting of the cutline by the width of the cutting tool +50% for outside, - 50% for inside and 0 for centerline again the Gcode eludes me.
The next issue is the actual cutting of a circle I have seen small straight cuts from polylines which would be incredibly difficult to get accurate and then I also saw these 'arc' cuts using a radius somewhere in the mix but an arc is part of a circle I assume this Gcode command can be used to create a complete circle but again the Gcode eludes me. That is why I am also looking for a good tutorial on the usage of Gcode, its syntax and functions like the arc I think it is G03 there is something about I and J values but nothing was clear in what I was seeing. A point in the right direction regarding this would also be appreciated.

Thanks
Jeff   

Jeff,
I would recommend: CNC Programing Handbook by Peter Smid

RICH