F U R N I T U R E & C A B I N E T M A K I N G 19

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C oming to terms with thefact that sharpening is anecessary irritation when

making furniture is only half thebattle. The other half is notmaking a meal of dealing with thisunwelcome distraction.

Last month I looked at thegeneral principles of sharpeningand now I’m going to examinetechnique in a bit more detail andin addition look at sharpeningcarving chisels, using some of thetricks of the trade that I havepicked up over the years.

The process of sharpening justabout anything involves the fourprocesses of grinding, honing,burnishing and stropping. At eachstage, with the exception ofgrinding, both of the faces thatform the edge – the bevel and theback – are worked on. Flatteningthe back of a blade was coveredlast month, and fortunately thisrather tedious part of the processonly needs to be done once.

Concluding his mini series on

sharpening, John Lloyd says his

methods require the minimum of fuss

■ GrindingGrinding gives the opportunity toquickly re-establish or change the angleof the bevel, and a hollow grind willresult in a bevel that can be honed andburnished to a razor-sharp edgequickly, with the minimum of fuss.

The shape of the grinding wheel isresponsible for giving a hollow, or

concave, grind, and a slow-turningwater-cooled wheel is the safest way toachieve this without the risk ofoverheating the steel.

To obtain the desired grinding angle,Tormek provide a handy yellow plasticgauge which is placed on the wheeland against the back of the blade, but itwould be easy enough to create a

similar home-made gauge out of apiece of Perspex. The most usefulangles are 25° and 30° and, unlessthere is time in your life for a littleindulgence, getting close to the desiredangle is going to be good enough – in my book a few degrees either sidereally isn’t worth getting worked up about.

No need to get stroppy

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Chisel ‘straight out of the box’ shows fairly rough grinding and a ratherjagged cutting edge

The as-it-comesback of the chisel

Using the Tormekplastic gismo to set

the grinding angle

John Lloyd trained with Bruce Luckhurst and gained a City &Guilds silver medal in Furniture Advanced Crafts. He now hashis own workshop on Ditchling Common, Sussex, where herestores and copies mainly traditional furniture. John is a fullmember of the British Antique Furniture Restorers’ Association.

Grinding chisel bevel onslow-speed water-cooledwheel grinder – in otherwords, the Tormek

PART 2

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20 F U R N I T U R E & C A B I N E T M A K I N G

■ HoningHaving ground the desired angle, it’stime for a little honing on a mediumbench stone. I’m sure there are morethan two ways of holding a chisel orplane iron for honing, but two methodsseem to work for me and for the peoplewho attend my sharpening courses:

EITHER grasp the handle or themain body of the blade in the righthand – if you’re right handed – andapply pressure above the bevel with thefingers of the other hand

OR cradle the blade between bothhands, with the top of the blade restingon both thumbs and the first andsecond fingers of each hand applyingpressure above the bevel.

The first method is perhaps moreconventional, but the second has a bitmore symmetry to it and can work wellin avoiding or solving the problem ofuneven honing, which results in askewed end to the blade.

Stand with your feet hip width apart –wobbling about is not a good basis forsuccessful sharpening – and, with thestone close to the edge of the bench,set the blade at the right angle bychecking for the lubricant ‘bow-wave’and locking the wrists.

TheoryNow the time will have come to start

refining the edge. Convention has it thatthe whole surface of the stone must beused during sharpening. The twoschools of thought on this matter haveit that:

EITHER the body remains stationaryand the arms move back and forth

OR the arms stay in one positionwhile the body rocks back and forth.

Either way, the scientists among youwill spot that unless the hands makethe necessary microscopic adjustmentsto their angle during this process, theangle of the blade in relation to thestone will change as the blade ismoved over the stone’s length. Notsomething that is ever a problem if ahoning guide is used, I hear you cry,

but life’s too short for honing guides. The reason that it is suggested that

the blade is moved up and down thestone is not to make the process morechallenging, but in an effort to achievean even amount of wear over thestone’s surface. If, however, this addeddimension proves to be too much of adistraction from the matter in hand, justwork in small circles in a small area andkeep moving the area on subsequentsharpening. After all, even if a diamondstone is being used and there’s no riskof it going out of shape, of course it willshow signs of wear if only one smallarea is used repeatedly.

Pract iceSmall, slowish circles in a smallish areaof the stone are a good starting point.Concentrate on keeping the angle fixed,rather than rocking backwards andforwards and trying not to fall over. If theangle is right, a narrow, dull strip willappear on the bevel just behind theedge, and because of the hollowgrinding, this will only take a matter ofseconds to achieve.

A glance at the bevel, and feelingon the back of the blade for a burr, willgive you an idea of progress. To eventhings up if necessary, adjustments

can be made in the finger pressureabove the bevel, but once again,perfection is not necessary.

Because all that is required is that aburr is formed along the whole width ofthe edge, a tiny bit of skewing doesn’tmatter; just make a mental note andadjust your technique duringsubsequent sharpenings.

Having taken the trouble to create aburr, it is removed by flipping the chiselover and rubbing the back on thestone.

This process also refines the surfacethat forms the other half of the cuttingedge.

Bevel after grinding on the Tormek Flattening back of chisel on coarsediamond stone

Chisel back showing grinding marks.Achieving flatness in the area of the bladebehind the edge is the critical bit; theslightly concave area behind the ground areawill reduce with subsequent sharpenings

“A hollow grind will result in a bevel that can be honed and burnished

to a razor-sharp edge quickly with the minimum of fuss”

“Unless there is time in your life for a little indulgence, getting close

to the desired angle is going to be good enough - in my book a few

degrees either side really isn’t worth getting worked up about”

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F U R N I T U R E & C A B I N E T M A K I N G 21

■ BurnishingMore refining is done using a finerstone for the burnishing part of theprocedure. A 6000-grit water stoneworks really well for this, but waterstones are very soft and it is veryeasy to dig great gouges in them.This does little to refine the blade andcertainly doesn’t enhance the stone.The only benefit of these stonesbeing soft is that they are very easyand quick to flatten using a piece ofglass and some 220-grit wet-and-drypaper, using plenty of water toprevent the stone from getting stuckto the paper.

Only the same small area of the

bevel that was honed needs to beburnished, but a burr won’t form thistime, the only visible difference beingthat the burnished bit will take on theproperties of a mirror. Even thoughthere’s no burr to remove, havingfinished working on the bevel, give theback a rub too.

■ StroppingThe final part of the process isstropping, see page 22, which doesn’tinvolve stomping around the workshopshouting at people, but is what barbersdo with their cut-throats with the strip ofleather that hangs on the back of theirchairs and keeps them razor sharp.

Two different hand-holds thatcan be used when honing bevel

Flattening 6000-grit water stone using220 wet and dry stuck to a piece of glassand lubricated with water

Burnishingbevel on 6000-

grit water stone

Burnished strip onbevel, just behindedge. The area willextend on subsequentsharpenings until thewhole bevel isburnished – then it’stime to regrind

“Stropping doesn’t involve stomping around the workshop shouting

at people but is what barbers do with their cut-throats with the strip

of leather that hangs on the back of their chairs”

“Concentrate on keeping the angle fixed, rather

than rocking backwards and forwards and

trying not to fall over”

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22 F U R N I T U R E & C A B I N E T M A K I N G

■ Sharpening carving chisels

Sharpening carving chisels is a slightlydifferent proposition to the techniquesdescribed earlier because the curves ofthe chisels make the previousobsession with flatness irrelevant.

Grinding angles stay the same atsomewhere in the 20° to 30° rangedepending on the level of abuse they aregoing to have to endure, and jigs areavailable to aid the grinding process.

Free-hand grinding will work just aswell but needs a bit of practice,preferably with a chisel that you don’tmind seeing disappear in a shower ofsparks.

Carving chisels, like any otherblades, need honing and burnishingusing bench stones, but this time thestone is set with its long side runningparallel to the front of the bench. Withthe chisel set at the right angle, it is

moved sideways along the length of thestone while it is rotated from one end ofthe bevel to the other. This may soundas if you need the suppleness of acontortionist, but while the chisel ismoved from side to side and rotated, italso has to be kept at right angles tothe stone, rather than describing an arc.It’s a bit of a knack, but by no meansas tricky as it might sound.

The resulting burr has to beremoved, but this time with a curved slipstone, and burnishing the bevel can stillbe done on the 6000-grit water stone.

Tr icky stuf fThe next technique is the clever bit. Ispotted some professional carversusing it when re-creating fire-damagedcarvings at a National Trust property inSussex. It is particularly useful for verytight curves and acute-angled V-gougeswhich don’t fit standard slip stones, sopresenting a sharpening challenge.

All that is required is a lump ofsoftwood and some chrome cleaner.Two straight parallel cuts are madeinto the end of the softwood, one withthe bevel and one with the inside ofthe blade, for a length of about 50-75mm (2-3in).

These cuts will by definition beexactly the same shape as the curve ofthe chisel because they will have beencut using the chisel.

A squirt of chrome cleaner is addedto the two carved channels, and thebevel and the inside of the chisel canbe drawn backwards over the curves inthe softwood, which are now covered ina very fine abrasive.

It takes seconds to give a chisel aquick rub on one of these softwoodburnishing blocks. Repeat every fewminutes to maintain a razor-sharp edgewithout having to go back to thegrinding and honing stages for quitesome time. ■

When honing the bevel of the carvingchisel, move the chisel from side to sidealong the stone while turning the chiseland holding it at an angle of 25° and atright angles to the stone – this makespatting your head while rubbing yourtummy seem ridiculously simple

John uses a leather strop withchrome cleaner

Burnishing the bevel on a piece of carved softwood with chromecleaner makes keeping a keen edge on a carving chisel a doddle