G03 COMMAND HELP!!

[hkfanatic]

ok im haveing a stupid beginner problem thats causeing my brain to melt.

im trying to cut a 180deg radius on the out side of a blocks sides

heres the blocks dimensions x 2.5 y 1.0 z 3.0

zero is in the dead center of the block.

im useing a 1.0dia endmill

heres how im programming it.

(starting at zero Assuming m3 and etc.. has been done)

N001 G0 Y-.938
N002 G01 Z-1.0 F2.0
N003 X1.250 (THIS IS WHERE THE ARC WILL START FROM)
N004 G03 Y.983 R1.001 (i want it to do an arc the same spot on the op side)
N005 G01 X-1.250
N006 G03 Y-.938 R1.001
N007 G01 X 0.0

so essentially it cut an oval shape into the out side of the block 1 inch deep

my machine acts like its a G01 cammand and doesent arc.

im not too proficiant at Gcode they only touched on it in school.

help!

thanks

[CNCRim]

Originally Posted by hkfanatic ok im haveing a stupid beginner problem thats causeing my brain to melt. im trying to cut a 180deg radius on the out side of a blocks sides heres the blocks dimensions x 2.5 y 1.0 z 3.0 zero is in the dead center of the block. im useing a 1.0dia endmill heres how im programming it. (starting at zero Assuming m3 and etc.. has been done) N001 G0 Y-.938 N002 G01 Z-1.0 F2.0 N003 X1.250 (THIS IS WHERE THE ARC WILL START FROM) N004 G03 Y.983 R1.001 (i want it to do an arc the same spot on the op side) N005 G01 X-1.250 N006 G03 Y-.938 R1.001 N007 G01 X 0.0 so essentially it cut an oval shape into the out side of the block 1 inch deep my machine acts like its a G01 cammand and doesent arc. im not too proficiant at Gcode they only touched on it in school. help! thanks

N001 G0 X0 Y-.938 (Insert start position)
N002 G01 Z-1.0 F2.0
N003 X1.250 (THIS IS WHERE THE ARC WILL START FROM)
N004 G03 Y.983 R1.001 (Typo should be Y.938)
N005 G01 X-1.250
N006 G03 Y-.938 R1.001
N007 G01 X 0.0

[hkfanatic]

thanks, that was'nt a direct copy of my program (i've read through it there are no typos, at least none that i've found yet i'll go back through)

my concern was that im not inputing the right perameters for the G03 command do i have to dictate X on that line as well???

i have this: N004 G03 Y.983 R1.001

should it be: N004 G03 X1.250 Y.983 R1.001 ???

[scadvice]

Most of my programming is via CADCAM now, but every once in awile I will hand input a program (25 yrs of it) And.... I still can get caught on a simple error that is stareing me in the face... S### happens...
This forum is a good way to fix being stupid ...grin...and save the blood pressure and alot of time when we brain fade! Steve

[beege]

Originally Posted by hkfanatic ok im haveing a stupid beginner problem thats causeing my brain to melt. im trying to cut a 180deg radius on the out side of a blocks sides heres the blocks dimensions x 2.5 y 1.0 z 3.0 zero is in the dead center of the block. im useing a 1.0dia endmill heres how im programming it. (starting at zero Assuming m3 and etc.. has been done) N001 G0 Y-.938 N002 G01 Z-1.0 F2.0 N003 X1.250 (THIS IS WHERE THE ARC WILL START FROM) N004 G03 Y.983 R1.001 (i want it to do an arc the same spot on the op side) N005 G01 X-1.250 N006 G03 Y-.938 R1.001 N007 G01 X 0.0 so essentially it cut an oval shape into the out side of the block 1 inch deep my machine acts like its a G01 cammand and doesent arc. im not too proficiant at Gcode they only touched on it in school. help! thanks

I'm not sure what you're trying to end up with here.
Y-.938 is going to take .062" from the minus side of your block.
X1.25 is going to put the cutter centerline on at the edge of your block
G03 Y.938 R1.001 is going to cut air to the far edge of your block
G01 X-1.25 puts the centerline of the tool again on the left edge of the part, taking .062" of material with it. (Finish dimension of the block (Y) will be .875)
G03 Y-.938 cuts air again to the near left corner
G01 X0 will finish the circuit, and take the rest of the .062 from the block.

Are you STARTING with a block that size, or are you FINISHING withthe block that size?
Do you want convex arcs on the ends, or concave? (concave gives you very sharp corners, the other doesn't).

Perhaps a better description of what you want is needed, as well as what you're starting with.

Good luck, lotsa brains to help in here.

[scadvice]

A little more detail... Steve

[tauntdesigns]

If I got this right you are setting the X,Y zero in the center of the block(1.25 from left edge of part and .5 from the lower edge) and wanting 1. radius starting at the bottom edge to top of part then a .5 flat on top and then 1. radius to the bottom edge again.

The z move at 2." a min may be a slow air cut but here's my code for it. It comes to the right bottom of part then ramps onto the part with a G2 move then cuts a G3 move cutting the radius then G1 move to the start of the next G3 radius cut and then a G2 move ramping off part.

g0x2.y-.5
g1z-1.f2.
g2x1.75y-.5i-.125j0
g3x.25y1.i-1.5j0
g1x-.25
g3x-1.75y-.5i0j-1.5
g2x-2.y-.5i-.125j0
g0z0
m30

Hope this helps,
Jack

[tauntdesigns]

After re-reading your post........are you looking for a .5" radius or 1" radius?

a picture would help(even if drawn with pen)

I also notice you were using R's.......... I used I&J incremental

[scadvice]

also tell us what control your using. S

[tauntdesigns]

Originally Posted by hkfanatic thanks, that was'nt a direct copy of my program (i've read through it there are no typos, at least none that i've found yet i'll go back through) my concern was that im not inputing the right perameters for the G03 command do i have to dictate X on that line as well??? i have this: N004 G03 Y.983 R1.001 should it be: N004 G03 X1.250 Y.983 R1.001 ???

I missed this post!

G2 and G3 need an X and Y unless your finishing point is the same as your starting point.

The X and Y is the finish point of the move (telling it where to go)
The I,J describes the distance to the center of arc from the starting point.(I being X direction and J being Y direction)
R describes the radius

Is that what you wanted.

Cheers,
Jack

[hkfanatic]

ok a little more info is definetly needed. im posting a pic of the finished part the reason the radiuses are cutting air and only skimming the corners is because its a progressive cut inward to help keep deflection and tool breakage down, its cutting mild steel and im running 2 ipm just to keep things slow right now once i get the program right i'll mess with the feed and speed.

heres a pic of the finished part, zero is at x1.25 y .5 from the left lower corner. the reason is at one point there is a peck drill cycle to drill the center out and its just easier (at least for me to do it that way)




the final diameter/ thickness of the parts is .630, the shelf is going to be done with a shell mill so i can under cut the stock.

its the outside im haveing a problem with again the tool doesent want to arc it just go's straight and by the last post i think i know what it is i didint put the X starting point into the G03 command

its a bunch of counter clockwise circles takeing .062 off until final dimension, a tool change to a shell mill then the under cut for the shelf. tool change to a 3/4 end mill to do the peck drill in the center, tool change to a letter O drill and peck drill holes at x.75 and x-.75, tool change to a 1/4 end mill and circle mill holes to final dimension at .75 and -.75 at .525 deep

the slot happens afer i cut the parts off the block and reset fixtures

im useing a bridgeport BTC-1 with a 24 Atc fanuc control.

im useing an old copy of master cam i got from school but the program crashes when i tried to do the outside profileing so i wrote the code by hand and thats where im getting tied up.

hope this is a little helpfull, i REALLY need to start making some chips. i'll post the full program tonight when i get home if needed

[beege]

So it looks like the radius end points in X are all X.750, X-.750, to get them concentric with the drillled holes. X1.25 just won't do... I'm not giving you all the answers, just hints to help you learn...