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Now needed to grind the ER32 taper in-situ to take out the accumulated slop: made a motorized drive from a hospital bed incline DC motor (and morphed the EMFGF into a spin fixture). Then made a better Dremel-like grinding spindle from a pin vise, bearings and an accessory mount to affix the whole goldberg to the CSG arm.
With motorized EMFGF clamped to the CSG table at the requisite 8 degree ER taper angle, went to town many times. Got the taper surface runout down to a slight waver of a .0005" indicator needle. The final mounted endmill runout was pretty much down to the quality of the collet and nut, and how much you can reef down on the nut while on the CSG table. In my case, a decent ETM collet/nut would do 6 tenths or better-- good enough for MacGyver endmill sharpening. Finally! Then ground the base and sides parallel to the spindle axis.
The $(%&# Flute Finger Rest Part:
More scrap iron components. But must not have qualms about hacking your CSG with some method to affix the rest. It has to be stiff in 3 axes, and stationary with respect to the CSG spindle and table. The finger is a modified 10-32 machine screw, canted 7 degrees left so that a typical endmill primary land relief angle can be easily eyeballed: bump the table left/right until the endmill face lines up with the finger axis and lock it down. Sharpie as Dykem and some hand scratching with the grinding wheel to confirm your eyeballing. (Eyeball easy for 2,4,6 flute endmills, 3 & 5 flute not so much.)
Continues. Pt3 Final
With motorized EMFGF clamped to the CSG table at the requisite 8 degree ER taper angle, went to town many times. Got the taper surface runout down to a slight waver of a .0005" indicator needle. The final mounted endmill runout was pretty much down to the quality of the collet and nut, and how much you can reef down on the nut while on the CSG table. In my case, a decent ETM collet/nut would do 6 tenths or better-- good enough for MacGyver endmill sharpening. Finally! Then ground the base and sides parallel to the spindle axis.
The $(%&# Flute Finger Rest Part:
More scrap iron components. But must not have qualms about hacking your CSG with some method to affix the rest. It has to be stiff in 3 axes, and stationary with respect to the CSG spindle and table. The finger is a modified 10-32 machine screw, canted 7 degrees left so that a typical endmill primary land relief angle can be easily eyeballed: bump the table left/right until the endmill face lines up with the finger axis and lock it down. Sharpie as Dykem and some hand scratching with the grinding wheel to confirm your eyeballing. (Eyeball easy for 2,4,6 flute endmills, 3 & 5 flute not so much.)
Continues. Pt3 Final