G code in 3-d

[chakaloso]

I need the code to make the cut where the 1-1/4 pipe is going to fit.

What will be the best way to do it.

[Edster]

you want to cut the surface with a ball mill? and no cam software?

You might be able to change the circular interpolation plane to yz instead of xy and write a program that follows the radius in y and z then stepover in x.

[chakaloso]

What will be easier or better to do??

[gar]

070920-1843 EST USA

Your drawing is very incomplete.

Assuming you have a vertical mill, then make a fixture attached to a rigid right angle plate. Mill with a 1.25" endmill, or do an arc with a smaller endmill. You can also do your end holes this way.

.

[Edster]

Yeah, I had a hard time visualizing the part from your print. Does the surface for the handlebar go all the way across the part?

Do you have any kind of cam software? I did some bending dies, for buss bars I make, years ago with bobcad. They were simialar to what your trying to do.

[Andre' B]

Don't need CAM for something that simple.
I ripped this out of larger program and had to edit it a bit so there may be a bug or two.

(X AXIS CENTER OF PART)
(Y AXIS CENTER OF PART)
(Z AXIS TOP OF PART)
()
#100=-3.750(X START)
#101=3.750(X STOP)
#102=1.25/2(RADIUS TO CUT)
#103=2.0(ANGLE STEP SIZE)
#104=0.276(DEPTH OF RADIUS FROM Z AXIS ZERO)

#105=2037(SPINDLE RPM)
#106=16.3(FEED IPM)

(#108 NOT USED)
#109=2(TOOL)
#107=0.1875(TOOL RADIUS)
#110=56(WORKSTATION)

(START AND END ANGLE SHOULD BE)
(BETWEEN 0 AND -180 AND THE)
(START ANGLE SHOULD BE)
(GREATER THEN THE END)
#111=45.0(START ANGLE OF RADIUS)
#112=-45.0(END ANGLE OF RADIUS)

T#109M6
G0G90G#110X0.000Y0.000
S#105M3
G43Z1.000H#109M8
#150=[-#107+#100](X START POSITION)
#151=[#107+#101](X END POSITION)
#152=0.000(Y RADIUS CENTER)
#153=#102-#104(Z RADIUS CENTER)
#154=#102-#107(RADIUS AND END MILL)
#155=#111(CURRENT ANGLE)
#156=[#152+[#154*SIN[#155]]](CURRENT Y)
#157=[#153-[#154*COS[#155]]-#107](CURRENT Z)
G0X#150Y#156
G1Z[#157+0.100]F50.0
G1Z#157F#106
WHILE[#155GT#112]DO1
#156=[#152+[#154*SIN[#155]]](CURRENT Y)
#157=[#153-[#154*COS[#155]]-#107](CURRENT Z)
G1Y#156F#106
G1Z[#157+0.050]F75.0
G1Z#157F#106
G1X#151F#106
G1Z[#157+0.500]F75.0(RETRACT)
G0X#150
#155=#155-#103(DECREMENT, COUNTER)
END1
G0Z1.000M5M8

[GlenBA]

If you’re just interested in cutting the concave slot in the bottom, why not just put it in a vise and run the length with a 1 1/4" ball nose EM 7mm deep?

[big_mak]

Better yet. Send them to me and I'll make them for you!!!!!

[chakaloso]

I do not want to buy a 1-1/4 ball end mill and a holder for just one part.

I program that can make that cotour will be cheaper because I can use any ball end mill.

[SRT Mike]

Originally Posted by chakaloso I do not want to buy a 1-1/4 ball end mill and a holder for just one part. I program that can make that cotour will be cheaper because I can use any ball end mill.

Cheaper in what way?

Lets say that you use a 1/2" ball EM instead - how smooth do you need it? If you want it to fit pretty accurately you are going to go with something like .005 stepover? Your surface finish will not look very good A 1.25" ball EM from McMaster is $65. I don't see savings when you consider time to do the NC program, and the lessened surface finish and MUCH longer machining time.

[Andre' B]

Well I gave him the code, I bet that beats shipping time to order a 1.25 ball mill.
If his mill is small a 3/8 carbide ball mill should make the cut just as fast as you could with a 1.25 and with a lot less pounding on and machine.

Just got some time to plot it, looks like it will work.
You may need to adjust the start and end angles to clear the part, make them 90° and -90° and you should be safe, will just cut air for a while.
Reduce the radius a bit and increase the step angle for a rough cut. The run a finish pass at the rad you want with a 1 or 2 deg step, run again with a smaller step if you want a better finish.

Screen shot was done at a 5° step to reduce clutter.