Back on track, FWIW:
These graduations were done with the little Dremel engraving cutter - something like $2 each. Set up on a rotab on the HF micro mill, then rotab rotated 90º to drill the corresponding detent holes. Used the shaft from a defunct dremel tool with collet held in a MT collet to hold the cutter, ran at fastest speed. Later engraved the division numbers on a New Hermes manual engraver.
Making Degree Graduations
Re: Making Degree Graduations
I use the dremmel engraving bits all the time even on A2, O1, & 4140 before harding ofcorse. I have also used there pointed tunstien carbide bit on hardened sreel.Alchymist wrote:Back on track, FWIW:
These graduations were done with the little Dremel engraving cutter - something like $2 each. Set up on a rotab on the HF micro mill, then rotab rotated 90º to drill the corresponding detent holes. Used the shaft from a defunct dremel tool with collet held in a MT collet to hold the cutter, ran at fastest speed. Later engraved the division numbers on a New Hermes manual engraver.
G0704 mill
Craftsman/atlas 12x36 lathe
4x6 vert-horz.band saw, Craftsman 113 table saw,and radial arm saw.
Craftsman/atlas 12x36 lathe
4x6 vert-horz.band saw, Craftsman 113 table saw,and radial arm saw.
Re: Making Degree Graduations
My compound came with a cheesy printed degree scale riveted to the cast iron base. It was neither particularly durable nor particularly accurate. You guys inspired me to get rid of it and engrave the scale instead. Unfortunately, clearance was an issue and dremel bits just weren't rigid enough or long enough. My solution:
It's a 3/8" round HSS lathe tool bit. Ground to a point by the simple expedient of chucking it up in a drill and slowly spinning it against the grinding wheel. Then a single gash with the edge of the wheel on centre of the bit to form a cutting edge.
It seems to work well spinning at 1000 rpm with a nice gentle feed. .007" depth of cut. I marked a 190° arc.
It's a 3/8" round HSS lathe tool bit. Ground to a point by the simple expedient of chucking it up in a drill and slowly spinning it against the grinding wheel. Then a single gash with the edge of the wheel on centre of the bit to form a cutting edge.
It seems to work well spinning at 1000 rpm with a nice gentle feed. .007" depth of cut. I marked a 190° arc.