b'A Happy Medium It is easier on the tool, he said. If they ramp in, that means they But if an end user chooses tohave to go back over it and ramp plunge-mill into a part, SCT sug- backout,hesaid.Whenyou said a significant number of custom- gests reducing the chip load 50%. are plunging, you are technically ers engrave graphite for EDMing aCetkovic agreed that ramping isdrilling.steel die used for moldmaking. the preferred method, especiallyJacksonconcurredthatwhen Then when you form a moldedconsidering that an engraving toolplunging, a chip load should be half part inside that steel die, he said,takes a DOC of less than 0.15 mmof what is appropriate for ramping.the numbers are already built in to(0.0059"). Ialwaysbackitofftomake that part. You are going to be feeding verysure the small tips do not have any fast with very light depths of cut,chance of chipping or breaking, Ramp or Plunge he said, so when you are ramp- he said.BecauseSCTsengraversareing downward, you are not rampingCoolantapplicationorlack small, relatively delicate tools thatdown at a very high angle. thereof is another aspect of mi-feature a small flat, White recom- However, because microengrav- croengraving that requires consid-mends ramping, or arcing, into aing does not go deep into a work- eration. Jackson primarily recom-workpiece material to help avoidpiece, Jackson said plunging ismends clearing chips with an air snapping or chipping the tool. more common than ramping. blast, but flood coolant directed Sphinx single-flute engraving mills are displayed.BIG KAISER Precision Tooling42SEPTEMBER 2020Engraving.indd 42 8/17/20 11:03 AM'