Setup tips for secondary angle grinds on larger Bull nose Rads on a JXT or a CM01P
Use the bar height stop to time the horizontal flute.
Use Step pin indexing pin Tilt the tool into the step (7 degrees) Set the angle to 22 1/2°
This plus motor tilt can be greater than or match the existing Flute OD secondary angle
The wheel height must be centered for both operations Rad grinding takes place i the center of a trued and dressed wheel
Grand secondary angle at the same radius as the primary angle.
Tool spindle rotated, (do not return the spindel to inline with X to prevent nicking the flute say off 10° clockwise, Because you are bringing the tool to the wheel at a 7 degree down tilt chasing the helix to produce a secondary angle on the radius
At the appropriate radius (same as primary) swing the tool, spindle 90° clockwise feed the upper axis in until there’s a match or suitable blend on the bottom (no additional clearance is required beyond the existing bottom primary
Cycle through the flutes the secondary grind should blend the bottom no need to over grind the bottom primary effort is to clearance angle side
Move the X axis off center (minus) to the left to place the grind the radius is farther up the tool
.050 in the case of .100 Radius seemed to do nicely
What we’ve done is to stay off the bottom because the adequate clearance already exists over grind the end but just tilt the tool with the step pin and move the existing radius in a bit towards center we move lower X a little so we can get the secondary a little higher on the tool
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