Milling a hole - start the EM in center of hole

I have received so much help here in just a couple of tries I thought I would try again (and hope that one day I know enough to repay all of the assistance I am receiving by helping others).

I have a hole I need to keep t within +.000 -.001

I predrilled a hole an then set up my milling operation to mill my hole to size. I want the EM to come down in the center of the hole but no matter what I try it plunges at the edge. I have tried creating a point in the center, tried creating 2 holes and setting up a pocket operation.

Is there any way to tell BC where I want my plunge point to be for a mill hole operation? Geometry start point just changes the direction....

You need to select a lead in option.

In the Pocket feature choose "Offset Pocket Out" and then follow below :-

You are wanting to "Plunge", so set your lead in to "Plunge" and then put a point in the centre of your circle and go to your Pocket "tree" and look for "Plunge Point" as in the attached image, right click on it and then choose Re/Select and then click on the point you have created and either right click and choose OK or simply hit your space bar, now re-compute your tool path.

http://www.cnczone.com/forums/attach...d=280732&stc=1

Hope that works for you, works here :D :D
I would have uploaded a file for you but you don`t say what version BC and Build # you are using :D :D

P.S. If you don`t like that you could always just use a "Spiral" lead in, wouldn`t even need to drill the hole then :D :D

Regards
Rob
:rainfro: :rainfro: :rainfro:

If you are doing it as a profile cut, use a right angle lead in. Take the diameter of hole you are cutting, subtract the diameter of your mill, and divide the result by 2. That will put the mill dead center. I prefer using profiles for critical holes. You can also set an overlap in the profile. Say like .05" so it will overlap where the cut starts and ends.

Thank you to both The Engine Guy and TonyW. Both methods worked and now I have 2 ways to approach this!

On using the point method I had to drop the point in Z to get this to work (caught that part on another thread ;) )