Re-editing My Blog Pictures

After discovering some of my original blog pictures elsewhere on the Internet, I decided to watermark them. So then, after completing this little chore this evening, I've done what I can for now, and will review this tomorrow. Hope it is aesthetically appealing!

Making a Sensitive Drilling Attachment for my Milling Machine

I have been feeling the need the last few years of either getting or making myself a sensitive drilling attachment. I admired Sherline's sensitive drilling attachment (Part #1012), but felt I didn't have the bucks to get one, so, I made one essentially based on their model. Below are the individual parts pics, and some assembly and final assembly. Drilled some holes in aluminum with a small #56 bit, and worked great.

I didn't know of a place in town to get the bearing for pulling down the drill, so I got one at our local Ace store in their Hillman boxes. Not the best, a little wobbly, but allows me to pull down on the lip flange of the bearing and control depthing with the drill bit.

Some notes on materials and what I did: The brass tube is 13/32 O.D., the inside shaft is 3/8 O.D. cold roll, the shaft fits inside the brass tube with hardly any side shake to speak of. The drill body is made of aluminum, internally tapped and threaded 3/4" 16 T.P.I. The drill body was drilled to near size of the tube, then bored out to allow the brass tube to be pressed into the body and loctited in place. The set screw guides the steel shaft and also prevents the brass tube of ever twisting in the drill body. I did some knurling on the main shaft so the bearing could be fixed in place, as the tolerances of the bearing were a little sloppy.

The whole project from start to finish would have taken (for me) about a full day with all parts at hand, fabrication of other parts, and cutting threads on the main shaft for the Jacobs chuck with the Sherline. One of the larger purposes I intend on using this for is to make Geneva stripes on some watch and clock movements, along with spotting or perlage besides drilling.

Thanks for looking!..........................gf