A thin leather panel with a folded edge on a wooden workbench beside a bone folder and hammer.
| |

Turning a Folded Edge on Thin Leather

ByPeter Joeseph 'Briefcase Maker' Kalafatis

The raw cut disappears. Every problem it had goes underneath.

A folded edge on thin leather is a small lie told well: you skive the margin, glue it, roll it over and press it down, and the cut that would have needed burnishing is gone, tucked under the panel where nobody sees it. I build in bridle, thick and stiff, and my edges get beveled and rubbed until they shine, so this is not the edge I reach for. That is exactly why it gets my respect. The fold has four places to fail, the skive, the glue, the corner and the stitch, and the scenario below takes one strip of thin leather through all four, in order, the way the trouble shows up at the bench.

Video: Cutting It Apart: What’s Inside a $285 Wallet?, from Gentleman’s Gazette on YouTube.

The skive is the whole job

Too shallow and the fold rides up. Too deep and the blade comes through the face.

Hands skiving the edge of thin leather on glass before folding it.

The task is plain. One thin panel, the edge turned under along one long side and around a corner. First the margin gets thinned. The Leather Dictionary’s entry on skiving describes the move: the outer edge is thinned toward the border so it folds cleanly and sits right against the parts it joins. Lee Valley sells a leather skiver for that work, a handled blade made to shave the edges and cut bulk at folds and laminated layers.

Here is the first thing that goes wrong. You skive, you fold, and a ridge stands up along the turn like a pipe under a rug. The margin was left too thick. In a leatherworker.net thread on folding edges, Andrew Chee gives a working rule: skive the edge to about half its thickness over twice the width of the fold, so a quarter-inch turn needs half an inch of skived margin. That is one maker’s figure. It is a decent place to start your scrap.

The second thing goes wrong the other way. The knife grabs, digs, and a slot opens in the grain side. In a thread on a folded-edge card holder, bikermutt07 tells the original poster to skive on glass, because a cutting mat grabs the blade while glass lets it glide; Matt S wants a paring knife with a flat back, sharp past what seems reasonable. The poster ended up on a marble board and a paring knife and found he had more control than with a safety skiver.

Jeff Peachey, a book conservator who writes about thinning leather with more care than anyone, says much the same in his guide to paring leather. When paring goes badly, suspect the knife first. A crumb of scrap under the piece can lift the leather into the blade and cut a hole. He builds the taper with several cuts at lower and lower angles, never one hard push.

Sweep the bench before the knife comes out. Sounds like housekeeping. It is the difference between a margin and a window.

The glue grabs or lets go

Contact cement does not forgive. Water-based glue does not hold until it dries.

Skive done, the margin gets glued and the fold goes over. Two opposite failures wait here.

The first is grab. Contact cement bonds the moment the two coated faces touch, which is the point of it and also the trap. In a thread on holding a folded-in edge, Pete describes Barge cement put on thin to both surfaces and left until it no longer feels tacky, then warns that once the pieces meet there is no pulling them apart. He offers rubber cement as the forgiving option. In a corner thread, Ferg reports his straight edge sticking to the glue before it was where he wanted it. Thumb on the wrong spot, the fold lands an eighth off, and the only fix is a new panel.

The second is slip. On a thread about turned edges at corners, DavidL says he was moving off PVA to contact cement because PVA barely holds until it is dry, and a fold that has to stay rolled over will not wait for that.

Once the bond is down, it holds. JoeSnuffie, in the folding-edges thread, says a properly glued fold can be pulled apart but the leather tears before the glue lets go. The same threads give the follow-through: Art, in the folded-in-edge thread, taps the bonded edge with a shoemaker’s hammer, and CustomDoug works the curve with a hammer and a bone folder after the fold is stuck down. The hammer is not decoration. It closes the bond and flattens the ridge the skive left behind.

Art also mentions seam tape in place of glue. It is one maker’s habit and worth a trial on scrap.

The corner bunches up

A straight fold is easy. A corner has more leather than room.

A mitred corner on a skived and folded leather edge, seen up close.

This is where the scenario turns ugly. The strip comes around the corner, and the margin on the inside of the turn has nowhere to go. It piles up, a lump under the face, and the corner stands proud of the panel like a knuckle.

The makers on these threads use three answers, and none of them is free.

Pleating is the first. In the rolled-edge corner thread, DavidL says plainly that you have to bunch up the corner, gather the extra and hammer it flat, and he says it suits very thin leather. Ferg answers that pleating comes out too bulky for his layered work.

Notching is the second. Ferg cuts a run of matching wedges out of the margin so the strip bends around the corner, one side of each wedge square to the long edge and the other at about thirty degrees on a ninety-degree turn, with the wide end allowing for the thickness being wrapped. He points to bookbinders’ rolled round corners as the place to learn it.

Mitring is the third. On the card-holder thread, bikermutt07 and gmace99 both say cut the corner at forty-five degrees. Gigi glues the two sides together first, then cuts through both at once with scissors, so the two halves match. RockyAussie skives the corner itself, starting the cut about one edge-thickness out and keeping the skive about as wide as the outer skin is thick, then presses the folded corner in and around with a bone folder or slicker. He also warms the leather gently after the glue sets, with a heat gun, a hair dryer or a lighter, and says to test first because light leathers scorch.

DavidL asked the thread how to stop the corner point from bulging. Nobody gave him a clean answer. That silence is honest. The corner is where folded work tells you how many you have done.

The stitch line runs out of leather

Thin enough to fold is close to too thin to hold.

Now the edge is down, and the corner sits flat, and a stitch line goes in. Here the skive comes back to collect.

In the corner thread, rickybobby warns readers to watch the edge thickness so the stitches hold. Ferg says the same and gives his own floor for heavy or high-wear spots, around one and a half to two ounces. The original poster planned to bend the edge after rolling it and worried about stress on the stitches; the thread agreed he had reason to.

The thinner the margin, the less leather each stitch has to bite. Holes punched close to a feathered edge open up, stretch toward the fold and walk, and once a hole has walked the stitch in it is holding air. In my shop, the stitch is the last thing I would trust to a sliver.

Factory work has fought this for a long time. A 1939 patent from United Shoe Machinery, US 2,177,785 for finishing leather edges, notes that shoe makers sometimes finished an edge by skiving it thin and folding it over, then offers its own grooved and cemented edge as a quicker, cheaper way to show only the finished surface. Even a machine company treated the fold as work worth trying to beat.

Fine goods show the payoff when it is done right. Gentleman’s Gazette cut apart a wallet to see how it was built, and the teardown found outer leather thinned at the edges so the folds lie flat, corners thinned and folded where layers meet, glue holding everything still for the needle, and an interlining fixed only at the edges so the layers can move without wrinkling. Thin cotton went behind the card slots in place of leather, to keep bulk down. Every one of those choices is a decision about where thickness is allowed to live.

Bookbinders have their own number. Peachey’s paring guide calls seven-eighths of an inch a reasonable turn-in width most of the time, enough room if the leather tears, not so much that leather gets wasted. That is a book over a board, not a wallet over a card. The idea carries. The figure does not.

Burnish or fold

I came in to defend the raw edge. My own cases argue with me.

A folded-edge leather card holder beside a burnished bridle leather strap end.

Here is my bias, out in the open. I am one pair of hands working bridle, and I hand-burnish my edges because that is the tradition the leather was made for. A burnished edge has nothing hidden in it. You can see the cut, the layers, the work, and if it was done badly you can see that too. A folded edge puts all of that underneath. It looks clean on day one and you learn its truth years later, when a corner lifts or a margin starts to fray from inside.

So the case writes itself: burnish what you can, fold only what you must.

Then I look at my own lined cases. On those, I use a latex-based edge paint, because it does a second job and glues the layers together while it finishes them. That is covering the edge too, and closer to the fold than I like to admit. Lined cases also get a stitched edge to hold the lining, where unlined ones go without. And my gussets are cut thinner than my panels so the case bends at the side without creasing the face, which is the folded edge’s own logic: put the thin leather where the bend is.

The fold is not a cheat. It is a different deal with the same leather. On thin goods, where there is no edge thick enough to rub into a shine, it is the honest choice, and the maker who can turn one cleanly around a corner has a skill I would not try to fake on a customer’s piece.

The scrap bin is the only place to learn it. Start there. Look at the ridge, then the corner, then the stitch, and see which one tells you the truth first.

More of this kind of work sits under Advanced Techniques.

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

DEEDYGO Genuine Bone Folder: A genuine bone folder for creasing and burnishing. See it on Amazon (affiliate link).

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

As an Amazon Associate I earn from qualifying purchases. A commission may be earned if you buy through this link, at no extra cost to you.

Sources

You Might Also Like

Similar Posts

Leave a Reply