[bobref]

I have been trying to write a conversational program with no luck for our Milltronics Centurian 7 to put a concave radius on the end of a round pin using a .062 ball nose cutter. The dia of the pin is .686 and the radius is .375. The problem I've been having is the cutter wants to make a pass on the outside edge of pin when it begins, then start inside. This will wipeout the end of my pin. Any help would be greatly appreciated. I have attached a dwg if it helps.

[moldcore]

Why not just plunge a .75 ball or at least a larger ball than .062?

[moldcore]

Sorry bobref, I didn’t get time to finish what I wanted to say in the above post. I’m not familiar with the Centurion 7 control but if you want I can create a tool path in Surfcam for you if you PM me. We just took delivery of a VM20 with the 8200 control that is supposed to do 3D on the control, something our older Centurion 6 couldn’t. Not sure if I’ll take time to learn it though. We use Surfcam for 100% of the programming as it is.

[ZZZZ]

Take a look at this example:

I used cad to get a couple of numbers, I could have done a couple of trig calculations to get them but the cad is faster.

Conversational Program C:\\parts\P0001
Event 0 of 5

Program Setup
Program name [CONCAVE RADIUS ]
Dimensions [Absolute]
Units [English]
Work Coordinate [---]
Setup Notes:
[ ]
[ ]
[ ]
[ ]
[ ]
[ ]
---------------------------------------------------
Event 1 of 5

Tool Change
Tool [Change]
Tl Chng Position X[ ]
Y[ ]
Tool Number T[1 ]
Tool Description [1/16 BALL END MILL ]
Spindle Speed S[5000 ]
Spindle Direction[CW]
Coolant [Flood]
---------------------------------------------------
Event 2 of 5

Tool Pierce - Start Mill Cycle
Z Pierce Feedrate [10 ]
Return Point [Clearance]
Clearance [.25 ]
Final Z Depth [-.2234 ]
1st Z Depth [0 ]
Z Increment [.025 ]
X Pierce Point X[0 ]
Y Pierce Point Y[.343 ]
Compensation [Auto Left]
Options [Round Walls(ball nose)]
Wall Radius[.375 ]Start Angle[23.816 ]
---------------------------------------------------
Event 3 of 5

Mill Geometry - Arc
Plane [XY]
Feedrate F[15 ]
Direction [CCW]
Center [Abs Center]
Arc Radius R[.343 ]
Arc CenterXC[0 ]
YC[0 ]
End Point [Polar]
End Angle AB[90 ]
Z[ ]
End Option [---]
---------------------------------------------------
Event 4 of 5

Tool Retract
End Mill Cycle
Point on part after tool retract
[Auto]
Call Island #[ ]Call Island #[ ]
Call Island #[ ]Call Island #[ ]
Call Island #[ ]Call Island #[ ]
Call Island #[ ]Call Island #[ ]
---------------------------------------------------
Event 5 of 5

End of Program
Spindle off [Yes]
Coolant off [Yes]
Z to Home Position [Yes]
X Position (Home relative)[ ]
Y Position (Home relative)[ ]
---------------------------------------------------

[bobref]

Thanks for the responses. ZZZZ I will give that program a try at work tonight. @ Moldcore your response about the .750 ball end mill is how we did it the last time. Worked OK but we have other pins that are the same style but dimensionally are different so were not able to do it that way.

[bobref]

Thanks ZZZZ. Ran the program and it worked fine. I have only been using the machine for a couple months so still stumbling through things. One thing I do question is the start angle? When I did my trig I came up with 23.845. So either my math is wrong or I do not know how or where to calculate it from. Would you be so helpful as to show me how to figure that out. It would be greatly appreciated. I also thought the machine had a trig help function as well?

Bob Ref