Need Help!- Haas lathe programming question

[machinistpaul]

Can anyone explain how I can machine a part then have the tool step over to repeat the same part and so on?...Im chucking on a piece of tubing and machining and parting off a ring off the end then need the program to step over and repeat the same process and so on..any help would be appreciated

[Geof]

Make your entire program a subroutine in a larger program and change the work zeros; like this


O00000
All the stuff you normally put at the top.
G10 L2 G90 P1 Z0. this sets G54 to zero
G10 L2 G90 P2 Z(-thickness of one part) this sets G55 to one part thickness
G10 L2 G90 P3 Z(-thickness of two parts) this sets G56 two parts thickness
G54 M97 P1000
G55 M97 P1000
G56 M97 P1000
G53 G00 X0. Z0.
M30
-----
N1000

Here is your program

M99

You set all your tool offsets in G54

Obviously I have omitted a lot of stuff but this gives the basic idea.

[machinistpaul]

Thanks Geof, but will this allow me to machine .062 thick rings and parting them off on a piece of iron 4 inches long till I get to the chuck??

[machinistpaul]

Thanks Geof..but will this allow me to machine and part off .062 rings on a piece thats about 4 inches long till i get to the chuck?..I need to make about 100 rings

[Geof]

You will not get 100 rings at .064 out of 4 inches.

Your oarting tool will be about 1/8 so each ring will use almost 0.2" of material which means you can get 20 out of your 4 inches.

You just have 20 G10 lines and 20 subroutine calls, I think Haas lathes let you use that many work zeroes.

[machinistpaul]

oh i know..lol...i plan on using a . 047 wide parting tool and using a couple pieces of stock..thanks for the help..ill try it out tomorrow

[Donkey Hotey]

I probably don't need to tell you this but...

If you're clamping on tubing, the walls will probably flex (unless it's really thick). That suggests that you can't really hold it very securely without buckling the stock or otherwise damaging it.

It sounds like you're planning to keep a bunch sticking out of the chuck so you can make lots of parts. That means the tubing could very easily compress, deflect, wobble, get on top of the tool and cause a really nasty crash.

Be really careful with your work setup. I'd be afraid if it were solid bar sticking way out of the chuck. Tubing just gives me the heeby-jeebies. I'd do 3-4 parts at a time and rechuck the stock. It's just not worth hurting yourself over.

[machinistpaul]

i will be chucking on a 4" OD x 3.5" piece of 1018...will be chucked on the thicker part of the material..im gonna turn and bore enough for one ring then part off then repeat...till i get to close to the chuck...to avoid chatter I figure having it stick out about 4 inches should be good...

[machinistpaul]

these rings at finished size are 3.740 od x 3.640 id .062 thick..so they are really thin...the tubing will probably buckle a little at the chuck...but i will take it easy and be careful with it..thanks bud

[Geof]

Put a plug in it at the chuck otherwise you run the risk of having it buckle a lot and get loose as you machine away material approaching the chuck.

If you are going to be doing many part-offs my procedure is a bit tedious to program and you cna do it incrementally in a loop something like this.


G10 L2 G90 P1 Z0.
M97 P1000
G10 L2 G91 P1 Z(-width) M97 P1000 L100
G10 L2 G90 P1 Z0.

M30
----
N1000

This shifts G54 ahead incrementally. I have to say I have never used this approach simply because it makes me nervous. If you make a mistake on the Z(-width) and L xount you might easily increment your way into the chuck.

[JWK42]

If you have macros active, here is another way to do multiple parts from a blank. The original G54 'Z' is saved at the beginning of each blank and reset after the last part is parted off. if you abort or hit RESET in the middle of a blank you will have to start over with a full length blank. We use this method to make washers.

Note-- While I was typing this I see Geof has posted a similar solution. Geof is right, anytime you mess with 'Z' shifting you cannot go to sleep at the wheel!!

%
O01000 ( HAAS LATHE MULTIPLE PART PROGRAM )
N30 #501= 20 ( NUMBER OF PARTS FROM EACH BLANK )
N40 #502= -0.109 ( Z SHIFT BETWEEN EACH PART )
N50 #503= #5222 ( SAVE G54 'Z' START POSITION )
N60 G54 M97 P90 L#501
N70 G10 L2 P1 Z#503 ( RESET 'Z' AXIS TO START POSITION )
N80 M30
N90 ( MACHINE PART LOCAL SUBROUTINE )
N100 ( TOOL 1 )
N110 ( MACHINE MOVES )
N120 ( TOOL 2 )
N130 ( MACHINE MOVES )
N140 ( TOOL 3 )
N150 ( MACHINE MOVES )
N160 G10 L2 P1 W#502 ( SHIFT G54 'Z' FOR NEXT PART )
N170 M99
%