"Projects" at georgesbasement.com

6. Archie England's Goodell-Pratt drill
Goodell-Pratt spindle thread was distorted
Sliding the G-P spindle out of the frame
The thrust bearing was rusted solid.
The chuck base wouldn't unscrew ...
By removing the spindle from the frame, I could place it between centers.
After some persuading, the thrust bearing came unstuck.
The first task was to clean up the end-most one or two threads which had been distorted by a previous owner's operation of the chuck without a key part.  Placing the spindle between centers allowed me to use a triangular file and a single point tool (a lathe threading tool) as a scraper to remove the distortion without affecting the appearance of the threads.
Two sizes of Goodell-Pratt jaws side by side
The completed chuck all apart
The base of the chuck contains an element that presses against the bottoms of the jaws when the shell of the chuck is screwed tighter onto the spindle.  The hollowed-out end of the spindle presses against the conical small end of the pushing element; the small contact area minimizes the frictional torque between the pusher and the spindle, so the chuck is self-tightening under load.

I also made a new set of springs as described above.  The springs have to be a close fit inside the holes in the jaws, and the wire diameter should be large enough to generate sufficient force to make the jaws spread out inside the shell, and yet not become coil-bound when fully tightened.

The knob that was on this drill had been adapted from another drill's side knob and was most insecurely attached.  I pulled out its threaded shaft and bored out the knob for a wooden sleeve, then made a new shaft from a handy 5/16-24 Allen head, stainless steel cap screw.  The new shaft is held onto the crank by a nut which I cut into two parts in the ratio 1/3 - 2/3. The thinner part became the outside lock nut and the thicker part became a threaded sleeve to fit inside the bored-out knob (3/8 inch inside diameter).  In the image at far right, I am turning down the shortened cap screw to fit the 0.205 inch hole inside the mahogany sleeve.  The round-nose turning tool left a generous radius at the junction between the shaft and its (still) threaded base.  I am taking light cuts because the jam nut and threded sleeve can't be very tight - they're all that are driving the shaft for the turning operation.
Extracting the knob's shaft
Boring the knob
Making the mahogany sleeve
Making the new shaft from a 5/16-24 stainless steel Allen head screw
The old belt protected the knob.
Three equally thick pieces of soft wood ...
Scrap Honduras mahogany became the sleeve.
Turning down the shaft to 0.203 inch.

Now the next part is serious: This is the method used to attach the pads to old braces - it's permanent, because the sleeve is glued inside the knob. 
The washer was peened tightly to the reduced-diameter end of the shaft, so the bearing surfaces are the opposite ends of the mahogany sleeve.
Assembled jam nut, threaded sleeve, and threaded shaft, plus mahogany sleeve and steel washer
Assembled shaft and sleeve
Drill back together, with Millers Falls protected-spring chuck behind it
The threaded sleeve is used to adjust the end play of the  mahogany sleeve on the shaft after the washer is peened onto the shaft to hold the sleeve in place.
Here's the assembly before I glued the knob on.  Thankfully, I thought to put a couple of drops of oil inside the knob - carefully, so as not to spoil the gluing process.  I bent the crank plate to improve one's wrist angle.
The drill is now all back together with a free-running ball thrust bearing and a smoothly turning knob ... while not the original crank and knob, its just as useful.

The replacement jaw retainer was potentially a nightmare - if I had tried to make it by bending sheet steel to shape - it wouldn't tolerate repeated adjustments/bends.  My solution was to carve the retainer out of the solid metal, as it's not called upon to deflect or to resist much force.  The saw cuts greatly sped up the shaping process.  Note how delicate its attachment to the jaw is ! 
Design 1 of the protected-springs chuck - before repair
Badly repaired jaw - apart
Making the replacement jaw retainer
Replacement retainer peened in place
Repaired retainer & jaw
Protected springs chuck
Unmatched jaws of protected springs chuck
The original chuck had a poorly fitted jaw.
The peened-in pin was hard to get out.
All together now !
Lots of space for the retainer ends.
The jaw tips don't match.

Whoa !  It turns out that there are two protected-springs designs of the Millers Falls chuck.  They are not interchangable, as the truncated cone that aligns the springs in the original patent has a pointed tip, a lot like the Goodell-Pratt chuck described above.  The alternative design has a smaller, cylindrical extension to fit against the drill spindle.  The original patent shows a third way ...  The protected-springs chucks that have the patent date imprinted in them are all the coil-spring, original design.  None of the chucks with the S-shaped springs has any markings, even though they were used exclusively on Millers Falls drills.  These are the size used on the No.2 eggbeater drills with either the LRRCW, two pinions, or both two pinions and the LRRCW. 
Coil-spring version of the protected-spring design
Assembled version of the coil-spring jaw and retainer
S-shaped spring of the second protected-springs chuck design
Second protected-springs jaw design
U.S. Patent 660,121, issued October 23, 1900.
Archie's jaw design in the patent.
An unmarked Millers Falls chuck with S-springs.
The connection to the spindle is different !