Torn leather strap squared off on a workbench beside a new replacement end, ready to repair.
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Repairing a Torn Strap End

ByPeter Joeseph 'Briefcase Maker' Kalafatis

A splice is a scar. Done right, it is the strongest scar on the strap.

A torn strap end is not a ruined strap, though it is a strap that has told you where it was weakest, and the repair starts by listening to that before any blade comes out. Splicing a broken strap was routine work for harness makers, and the method in the old farm bulletins is still the one to use: cut back to sound leather, thin both ends into a long overlap, and sew the lap with waxed thread. Glue holds it while you work. The thread holds it after that. Everything else is judgment, and judgment is where most repairs go wrong.

Video: Splitting an English Bridle Leather Strap, from Marcellino NY Briefcase Maker on YouTube.

Reading the tear before you cut

Look at the leather around the break, not the break itself.

Hands skiving a long taper on the flesh side of a leather strap end for a splice.

Leather that tore because it was overloaded looks different from leather that tore because it was finished. A clean rip through firm, springy fiber means the strap met a load it was never cut for. A ragged tear with cracking along the grain on both sides means the hide dried out and gave up, and splicing new leather onto that is sewing a new sleeve onto a coat with no back.

Bend the leather an inch or two from the tear, grain side out. Sound strap leather flexes and comes back. Dry leather crazes across the surface and stays bent. The Canadian Conservation Institute’s note on caring for vegetable-tanned leather warns that very dry conditions embrittle it and that long, thin pieces can crack if they are bent too far. A strap is exactly that shape. Test gently. The point is to find the weakness, not to finish it off.

Rub a thumb across the grain while you’re at it. If it comes away rusty and dusty, stop. The Museum of Fine Arts Boston’s CAMEO entry on red rot calls it an irreversible deterioration of vegetable-tanned leather, with a powdery red surface, cracking and loss of strength. No stitch fixes that. You’d be anchoring good thread in dust.

Bruce Martin, who runs Show-Me Harness Shop in Missouri, put the whole skill of this step in one line to Shop Talk magazine: “I can look at a piece and tell if it’s worth repairing.” That eye comes from seeing a lot of broken tack. Until you have it, the bend test and the thumb test will have to do.

Then decide the shape of the job. Either the strap can lose a few inches and still buckle, or it needs a new piece of leather spliced on to get its length back.

Cutting back to sound leather

The torn part is already gone. Stop treating it like it isn’t.

Square the end with a sharp knife against a steel square, well past the last crack or stretched hole you can find. Small Farmer’s Journal reprints an old Cornell bulletin on harness repair that still reads like a shop manual, and it says to square the ends before splicing and trim the corners. Corners left sharp catch on everything and peel first.

Cut more than you want to. Every maker’s hand hesitates here, because the leather looks fine a quarter inch from the tear, and a quarter inch is where the hidden split usually keeps running inside the layers. Grain can look clean while the flesh side is already letting go. Flex the new end again after the cut, and if it still crazes, cut again.

When the strap needs its length back, the new piece should match the old in tannage, weight and temper as closely as you can find. Firm vegetable-tanned strap leather against firm vegetable-tanned strap leather. A soft, oily piece spliced to a stiff old one will stretch at a different rate, and the splice will spend its life being pulled in two directions at once. Cut the new piece a few inches longer than the gap. The overlap eats that length.

On my own straps I don’t start from a single thick layer every time. I split strap leather down on an old hand-crank splitter and stitch two thinned pieces together, so the strap has a good face on both sides. The video above is me splitting a bridle strap down. For a repair, the same idea helps: a replacement end built from two thinner layers can be made to match an old strap’s thickness instead of just landing near it.

Skiving the lap

Long and thin wins. Short and thick makes a lump that breaks at its edge.

Macro of a saddle-stitched splice repairing a torn leather strap, with a cross-stitch at the tapered end.

The bulletin’s numbers are simple. Lap the ends two to four inches, and skive most of that overlap down to a long bevel on the flesh side, so that when the two ends sit together the strap is close to its original thickness the whole way through. Each end gets skived on the side that will face the other. One thins from the flesh. The other thins to match, so the two tapers nest like a lap joint in a floorboard.

That long taper is the whole reason a splice works. A short, steep step puts all the load on one line across the strap, and leather tears along lines. A long feathered lap spreads the pull over inches of glued and stitched fiber. On Leatherworker.net’s thread about splicing a strap, one member’s advice comes down to “a long slanted skived scarf properly glued and stitched.” Another skives the ends on opposite sides and joins them with contact cement before sewing. Different hands, same answer.

Skiving is a knife skill before it’s anything else. Weaver Leather Supply’s leather tool guide says hand skiving is useful for belts and keepers and admits it “can be tricky at first.” That is a polite way of saying the knife will dive and take a hole out of the middle of your taper the first few times. Keep the blade sharp enough to shave, keep the angle low, and take thin passes. Practice on the offcut from the end you just squared. It’s the same leather, and it’s already scrap.

Rough the two skived faces lightly and glue them with contact cement. Line the edges up before the faces touch, because contact cement grabs the moment it meets, and a crooked splice glued flat is still crooked. Hammer it down on a hard surface. The lap should now feel like one piece with a slightly stiffer middle.

Run your fingers along the edge. If you can feel a step at either end of the lap, the taper is too short.

Stitching the splice

The glue is a clamp. The thread is the repair.

Mark two stitch lines along the lap with wing dividers. The bulletin sets them about an eighth of an inch from each edge, sews with waxed linen thread, and doubles the strands for heavy straps. Start in the middle of the splice and work out toward the ends. It also says to cross-stitch the thin ends so they don’t curl up or snag. The feathered tips of the lap are the weakest leather on the whole strap, and a cross-stitch pins them flat where a single row would let them lift.

Holes go in first, all of them. I pre-punch and line up every hole on thick work, because heavy leather simply will not stitch otherwise, and a splice on a working strap is heavy leather doubled. Punch through both layers of the lap at once so the holes on the top meet the holes underneath. Martin told Shop Talk that when he sets new leather against old, “there may be stitching holes to match up.” Old holes from the original seam can line up with your new ones or fight them. Walk the line before you punch and decide which.

Then it’s two needles on one waxed thread, a saddle stitch, each stitch pulled tight through the same hole from both sides. I hand-stitch everything I make. A hand saddle stitch holds better than a small machine stitch, and a good one looks clean on both sides, which matters more on a splice than anywhere else because both faces of a strap get seen and both get rubbed. The hard part is the needle going through a hole that already has thread in it. Push the second needle through carelessly and it pierces the first thread inside the leather, and you won’t see it until the stitch lets go.

On a doubled lap of bridle the needles do not want to come through. I wax my needles and pull them with pliers through the thickest work, and a splice qualifies. Thumbs and forearms carry the rest. Pull each stitch to the same tension. A splice with one loose stitch in the middle is a strap with a hinge in it.

Tie off the way the bulletin does: a knot wound back through the last hole, and a second through the hole below it. Then smooth the stitches flat with something round and hard and tap the whole splice level on the bench.

Where a rivet is the honest answer

Stitched is stronger. That isn’t always the question being asked.

Repaired leather strap with a burnished, stitched splice buckled and hanging in a workshop.

I’ll state my bias first. I don’t put rivets on my straps. The buckles are hand-stitched in, and when I do talk hardware, my ranking is plain: hollow tubular rivets are the weakest kind, solid tubular are stronger. So I came into this one leaning hard toward thread, and the old bulletin backs me: “A stitched splice is stronger than one made with rivets.”

Read the next part of the same page, though. It says a broken strap may be “quickly and easily spliced by riveting,” that three rivets per splice are usually enough, and that the riveted splice is commonly used as a temporary fastening. Its one firm instruction about split rivets is to replace them with a stitched splice at the first chance. That’s not a sneer at rivets. That’s a farmer with a broken trace on a working morning, and a horse waiting.

Here my own argument runs out. A perfect stitched splice that sits on the bench for three weeks is worth nothing to the person whose strap broke today. Three solid copper rivets set right, with burrs peened down over them, will carry a bag strap home and keep carrying it. The rivet loses on strength and wins on time. The man with the broken strap usually gets to decide which one matters to him, not the man holding the awl.

And there’s the harder thing underneath. On a briefcase I built, I would rather cut a whole new strap than splice the old one. I know what’s inside a bad splice and what’s inside a good one, and both are still a splice. The leather is never one length again. So the craftsman’s argument for stitching over rivets is also, if I’m honest, an argument for not repairing at all, and the old harness makers who mended the same traces season after season knew something about thrift I’m not sure I’ve earned.

Finishing so the splice disappears

Match the old edge, not a new one.

A splice that works and looks wrong will get blamed for everything. Bevel the new edges with the same size edger the strap was finished with, then burnish them until they match the old edge’s shine and color, not until they look new. A raw new edge next to a ten-year-old burnished one reads like a patch from across a room.

Color is the slow part. The Leather Dictionary’s entry on light fastness notes that undyed vegetable-tanned leather darkens in light, so a new piece spliced to an old strap will start pale and catch up over time. Dye the new end to match, or let it close the gap on its own. Either way, condition both sides of the splice once the edges are done, using the same feed on old and new so they age at a similar rate. The care and cleaning pieces in From the Bench cover the feeding side of that.

Then flex it. Buckle it, unbuckle it, pull it hard between two fists. The splice should bend through its length, a little stiffer than the rest, without a sharp hinge at either end of the lap. If it hinges, the taper is short or a stitch is loose, and it’s better to find that on the bench than on a train platform.

More of this kind of work sits under Advanced Techniques. The man who makes these straps is on The Maker page.

Leather Skiving Knife Set, 2 Pieces: A two-piece metal skiving knife set for thinning leather edges. See it on Amazon (affiliate link).

Barge All Purpose Cement, Quart: A quart of solvent-based contact cement. See it on Amazon (affiliate link).

WUTA Wing Divider: An adjustable stainless steel wing divider for marking a stitch line. See it on Amazon (affiliate link).

John James Saddlers Harness Blunt Point Needles: A set of blunt-point harness needles, five sizes with five needles of each. See it on Amazon (affiliate link).

Mandala Crafts Waxed Linen Thread: A spool of waxed linen thread for hand sewing. See it on Amazon (affiliate link).

Beesworks Yellow Beeswax Bars, 6 oz: Yellow beeswax bars, 6 oz, for waxing thread. See it on Amazon (affiliate link).

Leather Carving Hammer Mallet: A nylon-headed mallet with a wooden handle for striking chisels. See it on Amazon (affiliate link).

YaeTek 6-Inch Manual Leather Skiver Splitter: A manual skiving and splitting machine for thinning leather. See it on Amazon (affiliate link).

Dritz 750T Double-Cap Rivet Tools: A metal rivet setter and anvil set for double-cap rivets. See it on Amazon (affiliate link).

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Sources

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