Rotary machining tool offset 4th axis

HI, for rotary machining 4th axis is there a rule for how much to offset the tool? I've searched the forum and the internet but I could not find a good guide. If I go off the 5th axis info I found 11 to 14 degree's. But that is 5th axis. I was thinking 1/2 the cutters radius for the offset.

Its just a round tube with a single neck

I for one have no clue of the question.

Are you talking about tool length offset?

11 to 14*? What's that?


I would always use actual tool length offset in a mill.

There are times when I doo use tool C/L on the lathe - if it is a full rad tool tho.
But then I end up having to chase that offset back and forth when I replace it with a regular grooving tool, so not sure that is even a good idea...


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Think Snow Eh!
Ox

I solved the riddle as to what the question means: the treasure is buried by the big oak tree in the cemetery by the river.

Ox, I thought you were better at riddles

The real answer is probably something like... depends on the SFM you want at the actual cutting contact point based on the angle of inclination of the surface.


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Not following the SFM idea?

I can see your idea if I were to have a tapered endmill in the spindle, but if I have a 3/8 mill in the spindle, it doesn't matter where I contact the part in the A, my SFM will still be the same.

No?

And if this was the case - I don't see how 4th/5th have any application in that issue?


The best that I came up with was in the case of say a 1/4 Woodruff cutter.
Offset the tool to C/L in Z, and then program to Z0?

Or use actual tool length, and program for Z-.125 (Z-.250 on a live lathe).


But then the 11 to 14* thing wouldn't seem to have any bearing, so that part has me



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Think Snow Eh!
Ox

Ox said:

Not following the SFM idea?

I can see your idea if I were to have a tapered endmill in the spindle, but if I have a 3/8 mill in the spindle, it doesn't matter where I contact the part in the A, my SFM will still be the same.

No?

And if this was the case - I don't see how 4th/5th have any application in that issue?


The best that I came up with was in the case of say a 1/4 Woodruff cutter.
Offset the tool to C/L in Z, and then program to Z0?

Or use actual tool length, and program for Z-.125 (Z-.250 on a live lathe).


But then the 11 to 14* thing wouldn't seem to have any bearing, so that part has me



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Think Snow Eh!
Ox

Click to expand...

I was guessing that he wants to tilt the part slightly while surfacing in order to not cut with the tip of the ball.


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Again - that would be a 3D (3X) issue just the same.

Not saying that doesn't mean that it's not what he is asking of course....



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Think Snow Eh!
Ox

G00 Proto said:

I was guessing that he wants to tilt the part slightly while surfacing in order to not cut with the tip of the ball.


Sent from my iPhone using Tapatalk

Click to expand...

I understand what you are saying FWIW, but it sounds lik the guy is wanting to cope the end of a tube or sumpthing.


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Think Snow Eh!
Ox

Sorry should have included pictures

I know what I want to say in my mind, but pictures can say so much more then words can. My fault for not including a picture. 3/16 ball end mill. I basically finish the part on that lathe except for a ring where the neck is. Then I put the part in the mill and rough the bulk of the material off. Two passes with the 3/16 ball. A course path to get an even height for finishing. A final fine pass for finishing. So if I'm climb milling with the 3/16 ball end mill is there a rule for the axial off set paths. I've already run three slightly different configuration and noticed a line from using the tool tip. This next batch I want to cut with the side of the cutter and try to minimize secondary finishing. I was planning on trying a tip axial offset of .045 which should put me in the sweet spot of the end mill as far as radius is concerned. But I figured I'd ask if

Ox said:

I for one have no clue of the question.

Are you talking about tool length offset?

11 to 14*? What's that?


I would always use actual tool length offset in a mill.

There are times when I doo use tool C/L on the lathe - if it is a full rad tool tho.
But then I end up having to chase that offset back and forth when I replace it with a regular grooving tool, so not sure that is even a good idea...


--------------------

Think Snow Eh!
Ox

Click to expand...

I probably wouldn't use a ball endmill for that. For rotary toolpaths like this, I would use a 3/16 bull endmill with a .060r. That will put the cutting area out away from the tip and have a large enough flat to leave a very good finish on the cylindrical portion of the part. There is no reason to finish the vertical boss using a rotary toolpath, its going to look like shit. I would come in and do a 3 Axis pencil toolpath around the bottom of the boss (Z normal to the top of the boss), which would clean up the sidewalls and junction of the boss in one shot. Then 2D face the top of the boss and 3 axis finish the radius on the top of the boss. Seems more complicated, but the finish will be substantially better and much faster.