Wednesday, February 18, 2015

Restoring a Millers Falls #2 Hand Drill

I got this drill for $38 from ebay, and I'm happy to report that everything seems intact and in good working condition, with the exception of the missing side handle.
Millers Falls #2 Hand Drill from ebay
According to this page at, it dates from ~1929-1931, with the reinforced body, triangle logo, and Millers Falls, Mass labeling on the handle.  I sprayed all the metal down with WD-40, let it sit for several days, and then took it completely apart.  Here are almost all the bits (the bearing races are stuck in the body at this point) along with the few tools I used to take it apart.  Back up the body behind the pins with a block of wood to prevent damaging the frame when you tap them out with a small pin punch.

All the pieces
I'll make a new side handle.  It should look like this, unless I don't make it that shape.  The thread appears to be 5/16-24.

I brushed off all the big chunks of grime with a small brass wire brush, and then used Purple Power degreaser with a Scotch-Brite sponge and a toothbrush to thoroughly clean all the metal parts and de-gloss the remaining paint.  The red paint on the wheel actually dissolved in the cleaner and I could have stripped it completely with a little soaking.  I used the cleaner at nearly full strength, which is pretty aggressive, comparable to lye with some detergent in it.

After that, I used some Testors model paint to re-paint the wheel (gloss dark red 1104TT) and body (semi-gloss black 1139TT) with a small brush.  The smell of that paint sure takes me back to childhood.

Before and after a little red paint
After the paint dried, I put the wheel on my lathe, by pinching it between a flat wood drive block and a conical live center.  I ran the lathe on the slowest speed and hit the outer rim with P400 and P600 sandpaper for a little polishing action.

The wooden top handle on this version is threaded and screws onto a stud that is pinned into the top of the metal frame.  You have to drive out a 3/32 x 15/16 pin from the handle's ferrule, then you can unscrew the handle from the body.  This drill's handle wiggled a bit so I unpinned it and discovered that the wiggling was in the connection between the stud and the frame.   I tapped on the pin holding it in, but it didn't want to come out and I didn't want to beat on it.  I dribbled some blue threadlocker around the joint and wiggled it to work it down into the threads.  After curing for 30 minutes, no more wiggling (after some use, I'll admit there is still some slop, but somewhat less).

The flat-head screw that holds the handle to the main gear was an incorrect replacement.  The female threads in the gear were a little worn, and I couldn't figure out if they were supposed to be 10-24 or 10-32.  I thought about using a tap to chase or re-thread the hole, but it was easier to get a 10-32 x 1/2" flat head brass screw and just gently force it in.  The brass may have got chewed up a bit, but the tight fit will just keep the screw from coming loose.  It's a bit shiny and new right now, but a little age will tarnish that brass to a decent look I think.

I made a new side knob from a piece of madrone.  It's a similar shape to the original, and I like the feel of it in use.  It's intended to be held by one hand, while you hold the top and apply pressure with your body, and crank with the other hand.  I doubt I will ever use this drill this way, since I have the luxury of an electric drill when the going gets tough.  The thing that's nice about these hand drills in a modern shop is the degree of feedback you get when drilling delicately.  At least, that what everyone says.  I think I've got enough hours behind a modern cordless drill that I can feel every bit of the cutting action, and no wiggling hand crank motion to ream out the hole.  I regret using a copper ferrule (a plumbing connector) instead of waiting until I could go to the hobby shop and pick up a piece of appropriate tubing.  The color doesn't go with the top handle ferrule, but oh well.  I can always do it again.

New side handle in madrone
I cleaned up the gunk from the knurling on the chuck by very gently applying it to a fine wire wheel on a bench grinder.  The chuck desperately needs to be taken apart and cleaned, but I don't have a pin tool to open the body.  I'll have to make one one of these days.  For now, I just blew a lot of WD-40 through it and got it working much more smoothly.

Update:  I picked up a Park Tools SPA-1 pin spanner for $10 at my local bike shop the other day while getting some parts.  It worked perfectly to take the back off the chuck, with the body gently-ish held in a wooden hand clamp.  I cleaned out the guts of the chuck and now it works almost as the maker intended.  There is a little scoring on the outside of the jaws such that if the chuck is closed down completely it takes a little nudge to get it to pop back open when the mechanism is loosened.
Ready to Use