Friday, June 30, 2017

More saws for renewal

I got two more Disston saws from my friend Amie for renovation.

The uppermost is probably the older of the two, and the better quality. It appears to be a Disston D-7 panel saw, made between 1928 and 1955. All of the fixings are in brass. It has been sharpened in a sort of a crosscut pattern, but in rather a half-hearted way — it's very nearly a straight rip-cut.

The lower looks like a skew-back Disston D-23 panel saw, a very common model that was made from 1911 right through to 1990. The fixings are of galvanized steel. The handle is almost completely machine-made with very little hand-finishing, except for a desultory spot of decorative surface carving. It's a rip-saw. It has a very slight kink in the toothed edge of the plate, possibly too slight to worry about, but I won't know that for sure until I actually try to cut wood with it.

Oldest

Less old
Both are missing fixings, to one extent or the other.

Oldest (left) is missing the stamped maker's-mark cap, but all the screws are otherwise present.

Less-old (right) is missing one of its cap-screws, and the handle is somewhat loose — most likely, it all just needs to be tightened up.

The plates have both suffered a bit from rust over the decades. I'll get them into a vinegar bath for a day or so of pickling and see how they come up, and then do a bit of polishing and sharpening.

The black spots are actually quite smooth and polished;
they look black due to the quirks of photographing reflective surfaces.

Coupla days....

This is the plate from the D7, after pickling and a bit of scrubbing with steel wool and various grades of wet-and-dry.

As you can see, the steel is quite badly etched by rust, probably beyond polishing with any reasonable degree of effort by me. I'd need to grind it right down on both sides, possibly reducing the plate thickness by as much as a quarter. There's a very clear difference between the areas that were exposed to moisture and oxygen, and those that were protected beneath the handle.

It doesn't make the saw unusable, but inevitably there's going to be a lot more friction on the plate within the kerf, and to compensate for that I'll probably have to increase the set somewhat.

Next day (July 3rd, 2017)

 All cleaned up, sharpened, and ready to cut wood.

This one, the D-23, has a handle made of apple wood. I noticed a bit of cell collapse when I was taking off the old dark varnish finish, so there are one or two soft spots — not rot, as such, but they could easily allow rot to start there. It may be worth applying a fungicidal coat to those areas maybe.
The D-7, with its woodwork cleaned up and brass polished, and its poor rust-etched plate. It's good steel and cuts perfectly well, though as I mentioned before I might have to increase the set a tad to keep it from binding in the kerf.

The teeth on this plate curve away from the edge towards the tip; I don't know if that's intentional, or a result of some over-enthusiastic sharpening — maybe at some point it lost a tooth there? Anyway, it doesn't seem to affect the cut, that I can can detect, and it's a very comfortable saw to use.

It's a pity it's lost its maker's medallion, but that has no functional effect.