Thursday, February 26, 2015

Restoring a Disston D-8 Panel Saw

A couple of years ago, I helped out in a neighborhood tool library.  We got a big influx of tools from one of our members' father's estate.  Among them was this little panel saw, quite rusty and far from usable.  The lower part of the handle was broken off, but I could read Disston on the medallion.  I thought it was highly unlikely that anyone would make use of it, so I asked the donor if I could have it, and he said ok.  It's hung on my tool rack for a long time.  I had some hope that it was a decent old tool, and I finally got around to restoring it this week.
Old Disston Panel Saw
I started by taking it apart, which was fortunately very easy.  The brass hardware is plated, which prevented corrosion inside the threads.  Then I wrapped a small piece of 220 grit sandpaper around a block of foam and applied a lot of elbow grease to the rusty saw plate, using plenty of WD-40 as a lubricant.  I used a scrap of plywood under the saw to prevent my bench from getting mucked up with the rusty oil slurry.  I wiped down the surface with paper towels, and another round with a new piece of sandpaper revealed the surface of the saw plate.

I was surprised to find that the etch was revealed, as well as the "10" stamped near the heel of the blade.  So I've got a 10 tpi Disston D-8 with a 20" blade, dating from somewhere in the 1947 to 1955 range, based on the "Disston USA" medallion.  The handle appears to be apple, not beech, which suggests 1947.  It was filed with a crosscut tooth configuration.

I'm going to make a new handle, maybe out of cherry, or maybe I'll go get a piece of apple or pear if I can find it easily.  The hardest part of making this handle will be forming the slot for the blade.  The D-8 slot was cut with a thin circular saw, which kept the top of the handle closed and helped hold the blade steady even if the hardware came loose.  This will be a challenge, since I don't have a circular saw that thin.  I might have to do something creative.

Another blogger cleaned up a nearly-identical saw last summer.  Take a look at Jonathan White's Bench Blog here.

Update:  Here's the saw, with a new cherry handle.
Cleaned up, but not yet sharpened
Here's how I got from here to there.  I took a blank of 5/4 cherry, and drew a rough outline of the handle shape using the old handle as a template.  Then I used the blade to precisely mark the location of the four bolt holes, and drilled them at the drill press with a 1/4" bradpoint bit.  Then I used a new 3/4 x 3tpi blade (to get a really nice cut) to resaw the blank in half at the band saw.  I smoothed the cut surfaces with hand planes, and then used the holes as a reference to draw the shape of the blade on the blank.  I also traced the handle again on this surface.  The area in between is the desired shape of the mortise.
Very shallow mortise will become the slot for the saw plate
I used a small router with a straight bit to cut a recess in the mortise area, the depth of the blade's thickness.  Then I glued the two halves of the blank back together, using a couple of 1/4" drill bits in the bolt holes to register the positioning.

After the glue set, but before it was totally dry and hard, I rough-cut the shape of the front of the handle at the band saw, revealing the thin slot mortise.  I ground an old hacksaw blade into a tool to clean out the squeeze-out at the bottom of the mortise, but after that bit of fiddling, the blade fit perfectly and snug.

I re-drew the handle shape of the blank, after using a jack plane to reduce the thickness by 1/8" or so.  After a visit to the bandsaw (1/4" x 4 tpi blade) and drill press (forstner bits), here's what the blank looked like.

The roughed out blank next to the original handle
Not very comfortable, but starting to look like a handle.  I took the blank to the drill press and made the shallow cups for the saw nuts and medallion with 1/2" and 7/8" forstner bits, respectively, and enlarged the holes on one side of the handle to 5/16" to accommodate the female half of the saw nuts.  The drilling was a painstaking effort, since the through holes meant I didn't have a center point to work from.  I just lined up the spinning bits as carefully as I could by eye, after tracing a circle on the surface.  I marked the side of the forstner bit with a thin blue felt pen to give me a consistent depth because the depth stop on my drill press is a piece of crap.  Next I used rasps to get right up to the layout lines, and then traced some contours with a pencil to help me form fair and consistent curves.

Offset layout lines help guide the rasps
  I recently bought this handle-maker's rasp from Tools for Working Wood, and it came in very handy for fine-tuning things and getting the inside of the handle shaped.  After about two hours of rasp work, I had the form to my satisfaction.  Another hour of hand sanding and card scraping got me to a comfortable and not too shabby looking end point.  There are a few flaws if I look closely but it feels good in my hand which I suppose is more important in the long run.  I put on a coat of natural Watco and will probably just add a little wax on top of that.

All done, with a coat of Watco
I used a Dremel with a fine wire wheel on low speed to gently clean up the saw nuts, and they came out pretty good with little effort.
The hardware cleaned up pretty quick with a small wire wheel in a Dremel


Wednesday, February 18, 2015

Corporate Joinery Sucks

Just and idea for a t-shirt or something.  The image could be a termite barfing, or maybe those stupid cam connectors that are ubiquitous on particleboard furniture.  I think I prefer the termite.



Have I been in Portland too long?

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 oldtoolheaven.com, 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