Sharpening Back Bent Gouge

A back bent carries its slope on the wrong side, and that changes where the machine has to sit. Every other gouge grinds with the support arm raised above the wheel. This one grinds with the arm dropped below it, and the jig pushed further out so the rim of the machine stays clear of your hands.

Have you ever picked up a back bent, turned it over twice, and quietly put it back on the shelf? Did the shape look like somebody had bent it the wrong way at the factory? Nobody bent it wrongly. It was made to reach where nothing else reaches.

The tool on my bench today is a number 25, thirteen millimetres, by Pfeil. Regrinding one is no harder than regrinding a straight gouge once you understand two things, and both of them are about geometry rather than skill.

What tells a back bent apart from everything else

• Most beginner sets contain straight gouges only, and the bent shapes arrive later, when a job finally demands one.
• Bent tools split two ways. Front bent, which has three members, and back bent, which has only two.
• Every front bent carries its slope underneath. Turn one of these over and the slope has moved to the top face instead.
• That one flip inverts the whole setup on the machine.
• The grinding itself is the ordinary sequence you already know, running from eighty grit through two twenty and on to leather.

What is a back bent gouge?

Bent means the blade curves along its length rather than running straight along its whole length. Where that curve begins, and which face the slope ends up on, is what separates the whole family.

Shape of tool	Where along the blade the bend begins	How many	Which face of it carries the slope
Long front bent	Almost at the handle, a long curve	One shape	Underneath it, on the inner face
Medium front bent	Somewhere between the handle and edge	Also one	Underneath, exactly like the long
Short front bent	Right by the edge, carvers say spoon	One more	Underneath again, on the inside
Short back bent	By the edge, bending the other way	Two only	On top, the outer face instead
Medium back bent	Further back, still bending backward	The other	On top as well, never underneath

Lay the two kinds beside each other and the difference stops being words. One hooks down, the other hooks up. Turn them over and the ground faces are on opposite sides of the steel.

A spoon gouge, which is what carvers usually call the short front bent, is the one most people meet first. The one bending the opposite way is what sits in my jig today.

Find where the curve starts and you can name any bent tool in two seconds. A long front bent starts leaving the straight almost at the ferrule, so the whole shank sweeps round in one gentle arc. The short one does nothing for most of its length and then turns hard, close to the tip. The medium sits between the two, bending somewhere around the middle, which is exactly as vague as it sounds and exactly how the trade names it.

Back bents only come in two of those, short and medium. No maker offers a long one, and I have never needed a third.

How do you clamp a back bent in the jig?

Same jig as almost everything else on this bench, which is half the reason I own it. A Tormek SVS-32 short tool jig, riding the arm of a Work Sharp 3000. One jig covers straight gouges, V-tools and this.

Two rules while you tighten it. The ground face points down toward the wheel, not up. And slide the tool all the way along toward the handle end of the cradle before anything gets locked.

Then check it is sitting square. I line the blade up against the little corner of the jig and eye it, then nip the screw down. A tool clamped a few degrees off will grind a few degrees off, and you will spend the next twenty minutes wondering what you did wrong.

That SVS-32 is the attachment I reach for more than any other, and it is worth saying why, because people see a Tormek jig sitting on a Work Sharp and assume it is a bodge. It is not. Tormek make the finest jigs in this trade and they make one for every awkward shape a carver owns. The arm on my machine takes all of them. So I get a flat glass wheel to grind against and Tormek geometry to hold the tool, and neither manufacturer had to agree to it.

Why does the arm drop below the wheel?

The slope faces outward on this shape, so the steel has to meet the abrasive from underneath instead of from above. A straight gouge grinds with that arm up high, where its edge never touches. Here it is the reverse, and if you do not move the arm you will simply grind air.

One more thing follows from that, and it is the part nobody warns you about. Set the jig too close to the machine and the outer ring of the housing sits right where your hand wants to be. Push it out further. Then find a spot where you can hold that distance without drifting back and forth, and stay there.

I eyeball the angle rather than measuring it, and I could not tell you the degrees on a back bent if you asked me. What I aim for is a slope running about three sixteenths of an inch back from the edge, five and a half millimetres.

About measuring, since somebody always asks. I do not measure. Not on a back bent, not on anything. I set the arm, offer the tool up, look at where the steel is touching, adjust, and look again. Two or three passes of that and the angle is right, and I could not put a number on it afterwards if my life depended on it.

That is not laziness and it is not mystique. A number only helps if you can reproduce it, and reproducing it needs a measuring setup you would then have to trust more than your own eyes. My eyes have been doing this for a long time. Yours will get there faster than you think, because the wheel shows you everything, and a marker on the slope shows you the rest.

How much metal comes off, and how fast?

Eighty grit does the shaping and it goes quickly. Barely any weight from my fingers. The steel comes off fast enough that you have to keep looking, and looking is the whole skill at this stage.

Watch the two shoulders. On this tool the right hand side needed a little more than the left, which happens on most blades and means nothing except that you keep rolling until they agree.

Stop before the edge. I leave about one hundred and twenty eighth of an inch, a hairline, and go no closer on coarse paper. Run all the way in at eighty grit and the edge comes out wavy.

What if the edge does come out wavy?

Very little, honestly. Steel thickness varies along a blade more often than people expect, so one point stands a fraction higher than its neighbour and a slight wave appears. Carving quality is untouched by it. What suffers is only how the tool looks to you.

There is a reason I raise this at all. The temptation, after an hour of regrinding, is to go back to the coarse paper and chase that wave until it disappears. Steel taken off that way never comes back, and the tool was fine before you started. Look at the edge, ask whether it will actually bother the wood, and let the answer be no.

I own wavy tools and I use them daily. Anybody who tells you a wavy edge is a ruined edge has never had to finish a panel by Friday.

Clean the wheel between grits. It takes five seconds and it stops the coarse dust you just made from scratching the surface you are about to polish. It happens every single time I change a face, and the only reason it is worth mentioning is that everybody skips it once and then wonders where the new marks came from.

Do not touch the arm height while you climb the grits either. Set it once for the shape you want and leave it alone until the shape is finished. Every finer paper then lands on exactly the ground the last one left, which is the entire reason the progression works.

Something else worth knowing about the paper itself. A sheet lasts far longer than most people assume, so the running cost of this setup is much lower than the sticker price suggests. I go through very few of them across a year, and the ones I do go through are working on every tool in the rack rather than one at a time.

Which grits, and can you skip any?

Four wheels, then leather. Eighty to shape, two twenty to wipe out the coarse scratches, then three thousand six hundred and six thousand, then a strop and a buffing wheel to finish. I leave the arm height alone the whole way through.

And yes, you can skip two of them. Three thousand six hundred and six thousand are not doing much for the carving. Two papers plus buffing is genuinely plenty. I go the extra distance because I want no micro marks left at all, which is vanity rather than performance, and I am not going to pretend otherwise.

After the last paper comes leather, and then the buffing wheel, which is where a bent tool finally gets its inside seen to. A flat strop will never reach into the hollow of a curve like this, so the hide has to be loose enough to fold around it, or the felt has to sit proud enough that you can use its rim. That half of the job has seven videos of its own and I am not going to compress it into a paragraph here.

What I will say is that the finishing is not optional on a bent shape, whatever you decide about the polishing papers. The inner face of a curve is exactly the part a flat surface cannot touch, so it is the part most likely to be left rough. That is where I would spend the extra two minutes rather than save them.

One economy worth copying. A glass wheel runs about twenty dollars, so I use both faces of every one and keep four or five in rotation, though three see most of the work. You can glue abrasive paper onto a half inch MDF disc instead and save the twenty. I prefer glass because the paper peels off cleanly and swaps in seconds.

The paper itself is the original Work Sharp stock. Quality is genuinely good and it outlasts cheap paper by a wide margin, which makes it cheaper in the end. Woodcraft carries alternatives if you want to compare, and Flexcut sell shaped blocks for the stropping half.

Everything else in the course goes the same road with one detail changed each time. The straight gouge is where anybody should begin. The V-tool has three surfaces instead of one and defeats more people than any other shape, which is why a second lesson exists for when it still fights you.

Then the rest of the family. A large gouge across four videos, a fingernail, a skew bent that argues with every jig, micro tools too small for one, diamond discs, and the L-bracket I bent so nobody has to buy the Tormek arm. Thirteen lessons sit in the whole course.

One habit closes the whole thing, and it costs nothing at all. Keep looking at the tool. Lift it off, turn it into the light, find where the metal has gone and where it has not, then put it back. That happens constantly on a single blade, it costs nothing, and it is the difference between arriving at a clean edge and arriving at a surprise.

Here is the part I will not soften. This is not a tool you need on day one, and buying one before you can sharpen a chisel properly is money spent for nothing. Learn the straight one. Learn what a good slope feels like in basswood, on a stone or on a wheel, whichever you can afford. Then come back for the bent shapes, because by then you will know exactly what you want them to do. Come and learn it in order.

Shall we carve?