Denford Software & Machines

Hi, I have a problem, how to make teeth if at all possible, what G or M code to use. I use DENFORD software VR Turning Cyclone.

Thanks.



My program:

N020 G21
N030 G99
N040 M06 T0101
N050 G97 M03 S1500
N060 G00 X120 Z-1
N070 G01 X-2 Z-1 F0.05
N080 G00 X120 Z0
N090 G71 U2 R0.5
N100 G71 P110 Q180 U2 W1 F0.1
N110 G00 X90 Z0
N120 G01 X90 Z-7 F0.05
N130 X97 Z-7
N140 Z-18
N150 X103 Z-18
N160 Z-27
N170 X120 Z-27
N180 Z-50
N190 G70 P110 Q180
N200 G28

N210 M06 T0201
N220 G00 X0 Z0
N230 G01 Z-15 F0.05
N240 G00 Z5
N250 G01 Z-30 F0.05
N260 G00 Z5
N270 G01 Z-45 F0.05
N280 G00 Z5
N290 G01 Z-60 F0.05
N300 G00 Z5
N310 G28

N320 M06 T0301
N330 G00 X5 Z0
N340 G71 U1 R0.5
N350 G71 P360 Q370 W0.05 F0.05
N360 G01 X25
N370 Z-60
N380 G70 P360 Q370
N390 G28

To make teeth like that you would need a live (spinning) tool on the Cyclone and full spindle (C axis) control - in other words it can't be done with what you have.
There may be some kind of gear cutting attachments available for standard lathes, but I don't know - hopefully someone else can advise on that...

The slots in this component would normally be cut using a rotating cutter, but in this case it would (in theory) be possible to cut them using a fixed cutter (as in a slotting head or a shaper).
The key thing is to be able to index the work piece.

a) Indexable headstock
Some (hobby use) manual lathes have basic indexing features in the headstock - i.e. a ring of say 32 holes in the chuck backplate and a plunger to locate the stationary spindle. Others, such as the Myford which is very common in home workshops, have indexing attachments that can be bought or made like this one.
With either, the work is held in the (non-rotating) chuck as normal and the cutting tool (either rotating, powered by an auxiliary drive) or fixed in the tool post moved around the work. None of these will work with a CNC headstock though, I don't think.

b) Indexable workholder
Without that feature, the only other option is to use an indexing head (a '4th axis' in milling terms). The 'home shop' solution is to mount one of these on the lathe cross-slide and hold the rotating cutter in the chuck.
I guess that standard CNC lathe control software only does 2 axes, so you'd need a manual indexer and lots of interupts in the program.

Hope all that makes sense.

For a 1-off job though, it might be easier to find a mate with a CNC mill and 4th axis though!

Andy