How To Restore A Hand Saw

A handsaw is two things bolted together: a thin plate of tensioned spring steel and a shaped wooden handle held on by a few nuts. Almost everything that makes an old saw look like scrap — orange plate, black handle, grubby brass — is surface deep and reverses in an afternoon. There is exactly one fault that does not, and the whole point of assessing before you start is to find it before you have spent the afternoon.

The same logic runs through the rest of this site: a very short list of faults is fatal, and everything else is cosmetic. The pre-purchase version of that list is on buying used hand tools; this page is what to do once one has followed you home.

1. Assess before you touch anything

Sight down the plate.Hold the saw by the handle, close one eye, and look along the plate from heel to toe as if it were a rifle barrel. It should be dead flat and straight. A gentle overall bow is often livable and sometimes improvable; a sharp crease — a kink — is not. A kinked plate will never track straight again, because the steel has yielded and lost its tension locally, and re-tensioning a plate is a smithing skill and not a restoration one. More on that limit at the end.

Look at the tooth line. Deep rust pitting that has eaten into the gullets and tooth tips is close to fatal, because sharpening removes metal and you cannot file teeth back out of craters. Even, shallow surface rust on the plate is nothing. Pitting along the toothed edge is the thing that decides whether this is a user or a wall-hanger.

Check the plate near the nuts and around the heel. Cracks radiate from the nut holes and from the sharp inside corner where the plate meets the handle. Run a thumbnail along any suspicious line; a crack catches. And find the etch— the acid-etched maker's logo, usually a few inches out from the heel. It is faint, it is easily sanded to nothing, and it is most of what tells you what you have. Note where it is now, because your job during cleaning is to work around it.

2. Take the handle off

Back out the saw nuts and separate the handle from the plate. Wood and steel want opposite treatments, and you cannot clean either properly while they are married.

Two kinds of nut turn up. Later saws use domed medallion nuts with an ordinary slot. Older saws use split nuts— a slotted collar that a standard driver will instantly chew and spread. Split nuts want a split-nut driver, which is a flat bit relieved in the center so it drives the two shoulders and not the thin bridge. If you do not have one and the saw is worth it, grind an old screwdriver to fit rather than mangle irreplaceable hardware. The round brass medallion is the maker's badge; note its orientation so it goes back the right way up.

3. Clean the plate

There are three routes, and the choice is mostly about the length of the plate and whether you care about the etch.

Chemical soak. A chelating remover such as Evapo-Rust, or a citric-acid solution, does the gentlest job and leaves the etch alone because it only attacks oxide. The problem is length: a 26-inch panel saw does not fit in any normal tub. A wallpaper trough, a length of vinyl gutter capped at both ends, or a long shallow tray solves it. Chelating removers are slow, reusable, and forgiving. Acids are faster and will etch the bright steel and encourage aggressive flash rust, so rinse and dry the instant they come out. The general method comparison is on rust removal and prevention.

Abrasive.The traditional saw-doctor's approach and the one most people reach for. Flat sanding block, wet-dry paper, and a lubricant — mineral spirits or a light oil — sanded along the length of the plate, never across it and never in circles. Start around 220 grit and climb only as far as you actually want to go; 320 or 400 leaves a clean satin plate that still grips a pencil line. Keep the block flat and keep well clear of the etch. Do not put a random-orbit sander on a saw plate: it rounds the plate, blurs the etch, and heats the steel.

Scraping. For thick scale, a single-edge razor or a card scraper held square to the plate shears the crust off before you ever reach for paper, and it is faster and cleaner than grinding through it.

Whatever you use, the plate comes off bright, bare and hungry for rust. Wipe it down with an oil or paste wax the same day — a freshly cleaned plate will bloom orange overnight in an ordinary garage.

4. Revive the handle

Vintage saw handles — totes — are usually apple, beech or occasionally rosewood, and they are almost always better shaped than anything on a modern saw. Treat the shape as sacred.

• Clean, do not soak. Mineral spirits and a rag or a brass brush lift decades of grime. Keep the tote away from water baths, which raise the grain and swell the wood around the nuts.
• Strip only if the finish is failing.Most old totes wear a shellac finish that dissolves in denatured alcohol; wipe it off with alcohol and a rag rather than sanding. A card scraper handles stubborn spots without rounding the crisp lines and the maker's stamps.
• Repair before you refinish.Thin cyanoacrylate wicks into hairline cracks; an open split wants glue and a clamp. Chipped horns — the pointed projections top and bottom — can be built back with epoxy or grafted, but a chipped horn is cosmetic and plenty of good users have one.
• Sand lightly, if at all. Knock off fuzz and feather repairs; do not reshape. The handle fits the hand because someone drew it that way and a century of hands wore it in.

Refinish with an oil, shellac or wax — the trade-offs are the same for every wooden tool part, and they are laid out on restoring wooden tool handles. An oil finish is the most forgiving and the easiest to renew, which is why it is the default for a user saw.

5. Nuts, medallion and reassembly

Clean brass gently. A brass brush on brass does nothing harmful, and a metal polish brings up the medallion, but stop before you buff away the maker's name. Reseat the handle, start every nut by hand to avoid cross-threading soft brass, and snug them — the handle should be firm with no play, not crushed.

6. Jointing, setting and filing — the overview

A clean saw with dull or uneven teeth still will not cut, and sharpening a saw is its own craft. In outline it is three passes:

1. Jointing— run a flat file along the tooth tips to bring them all to one line, so every tooth ends up the same height.
2. Setting— bend the teeth alternately left and right by a small, even amount so the kerf clears the plate. Too much set wanders and wastes wood.
3. Filing— a triangular file shapes and sharpens each gullet, rip or crosscut depending on the saw.

The full procedure, including which saws you can even sharpen (impulse-hardened teeth cannot be filed) is on how to sharpen a hand saw. A cheap, straight-plated vintage saw is the ideal thing to learn it on.

The re-tensioning limit, plainly

A saw plate is tensioned at the factory by hammering and smithing the steel so it stays flat under the stresses of a cut. You cannot add that tension back at a home bench. Gentle bows can sometimes be coaxed flatter, but a genuine kink, a lost-tension plate that buckles in the cut, or a plate creased by being stood on is a wall-hanger — a decoration, or a source of spare nuts. Knowing that up front is exactly why step one is to sight down the plate before you spend an afternoon on the rest of it.