I have a need. There were a number of un-identified reamers that I need to officially know their sizes. My milling machine doesn't have the reach, and I don't want to chuck up long bars of stock sideways to be drilled. The best option I came up with was the old Craftsman Port-A-Lign. It's led to some newer variants, but those were mostly plastic, and I struggled with those thoughts - the Craftsman has the drill chuck centered between the rods, and that makes me think it will be a better option to abuse.
Starting out, I need more length (some of these reamers are much longer than jobber drill bits). I grabbed the diameter of the rods for this as 0.496" :
Next up was to identify the spindle that the chuck sits on. It's a 3/8-24 thread, but I'm missing part, and also the chuck is a 3/8" chuck. I needed to be able to handle a 3/4" diameter reamer, so a new chuck was in order, and none of those have a 3/8-24" thread mount. That means I need to make a new spindle, with a JT3 mount on the end for the 3/4" chuck.
I pulled the spindle out. Two clips hold that spindle in place :
I found a 9mm socket fit perfectly on the end to drive that spindle out. I got my measurements :
(Not written down is the JT3 taper end, which is 1.2188" long, and the two ends are 0.7461" and 0.8110", or a taper-per-foot of 0.639", and an angle off of center of 1.5251 degrees.)
I chucked the new drill attachment into the lathe (1/2" straight shank, with a JT33 end for a 3/4" drill chuck), and cut a groove down to 0.467" (inside diameter for the new e-clip). Next the shaft went into the freezer, and the chuck went onto a heater vent to get a good temperature differential for assembly.
So, I have a fully functional Craftsman Port-A-Lign with two interchangeable chucks, the original chuck, and a 3/4" banger for use in first drilling, then reaming a hole. It's only to test reamer sizes, remember? Sheesh, my memory has really taken a hit with this chemo thing.
