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Signature tools

If you turn wood for long enough, it is quite likely that you will gradually tweak the standard turning tools to suit your own preferences. They can slowly evolve over time, by accident or design, for example to a different grinding angle or edge profile. If you look at tools belonging to another turner you may think that, while some would need re-shaping before you could use them yourself, others seem worth copying.

Signature tools

Some well-known turners have taken this a step further and put their own signature tools on the market. I’ve bought some of them and perhaps you have too.

I believe though that these tools  often have little or no advantage over the traditional ones. Few of them will make you a better turner. Only practice does that. If you know what you are doing, you can do a good job with almost any tool. For example, I like a shallow fluted spindle gouge for turning small bowls (not with the normal spindle grind of course), while most people prefer a deep fluted one. You can use either. An Ellsworth bowl gouge works very well, but that doesn’t mean my gouges don’t.

Alan Lacer skews

I recently purchased a couple of Alan Lacer skew chisels and wrote about them here. They are excellent tools, well made (except for a problem with the grind described in that post), nicely finished, heavy and strong. The main difference between the Lacers and other skews, apart from their weight, is the shape of the edge. It has a straight section at 90 degrees to the side of the blade and a sharp curve down to the short point. It gives them what I think of as a ‘humped’ appearance. I wasn’t sure that I would get on with this shape, but thought that if necessary I could reshape the edge.

After a trial, I’ve decided that I don’t like the Lacer edge profile. I re-ground them to a gently curved edge as popularised by another turner, Richard Raffan, and now like them better. It’s just a personal preference. I’m not for a moment suggesting that Mr Lacer got the shape wrong or that they aren’t a good buy.

Other designs

There are several types of skew chisel – straight edge, curved edge, oval cross section, rolled sides and round bar. At one time you could buy a square section skew with a diagonal edge going from corner to corner. But I think we can learn from the old time production turners from the 19th century. They had to work hard to make a living and didn’t like to waste time or money. Their tools were tried and tested over generations, and had were effective and efficient in use. Their skew chisels were straight-edged, with long bevels. This made them easy to hone. That was important because they used carbon steel, which doesn’t keep its edge as well as modern high speed steel.

They also used wide square chisels, with no skew angle. They are partly interchangeable with the skews. But the square works well for planing. It’s nice that you can just flip it over to get a fresh edge, so one sharpening lasts twice as long. The skew is better for detailing and cutting end grain.

End grain trimming

Easy end grain trimming is one of the main purposes of the skew angle. When cutting in with the long point, with the chisel placed vertically on its edge on the rest, long point down and with the bevel perpendicular to the cylinder, the skew angle keeps the edge clear of the wood and catches are less likely.

If you use a square-across grind for this cut, you have to tilt the tool to the side to keep the cutting edge clear. So the Lacer, with no skew angle at the long point, is not ideal for end grain trimming. Nor is any tool with rolled edges on both sides. Of course you can still use them for this cut. The Raffan curved edge meets the long point at a skew angle, so works well for end grain trimming.

Both the Lacer and the Raffan skews can peel cut very well.  The Raffan curved edge does not  leave a true cylindrical shape without a separate planing cut. Both can peel down to an existing cylinder without the short point marking the wood.

So after a while I shall probably grind the Lacers yet again. This time, to a traditional old-style straight-edged skew, with a nice long, honable bevel.

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Last job on the redwood globe stands

Today I finished the last job on the redwood globe stands. At least, I hope it is the last. The stands still need polishing and assembly of course, but I don’t have to do that.

The stands each have a big mahogany disc resting on heavy stretchers connecting the four legs. In the middle of each disc will rest the pedestal that I made a few days ago, and between the pedestal and each leg is a decorative button. It is these buttons that I made today.

I had saved some small offcuts of the figured redwood from the leg blanks. I cut some 80 mm discs with the bandsaw, then held them in the stepped engineer’s jaws of my old Axminster chuck. I faced off one side, turned a recess for the small dovetail jaws of another chuck, and made a small V at the centre. Rather than finish the job on my spindle lathe, I wanted to stay on the Graduate for better access, so simply held the small chuck in the bigger one. This increased the overhang, and would not do for all jobs, but these pieces were small. I quickly turned the discs to finished thickness with a bowl gouge and formed a shallow dome on the upper surface.

After sanding, I used the drill press to make a blind hole in the lower side. The  button can now be glued to the mahogany disc with a short locating dowel. The figured wood should look great when sealed and waxed.

This whole job has been a lot of work, cutting and gluing up some large blanks and turning big components at the maximum capacity of my lathes. There has been little room for error, as there was only just enough wood. Any extra would have been hard to source, and very costly. I’m looking forward to seeing the finished stands with their globes installed before they are exported to the client.

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More work on the large redwood globe stands

Some time back I posted about making a pair of large globe stands from reclaimed redwood. I made the leg sections, but put the feet on hold because when cut up I found the wood too wet. Cut to length, with exposed end grain for the moisture to escape, they are now dry enough to finish turning them.

Each blank, about 200 mm  long and 180 mm square, was rough turned to a cylinder with a small spigot on one end. I held the spigot in a chuck while drilling a 12 mm hole right through using an auger with a T handle. I then transferred the blank to my homemade chuck with the tapered steel insert (which is proving very useful for this type of work) and turned the foot with tailstock support. Fairly straightforward, but a little nervy, as there is no spare timber – no mistakes allowed! I double checked all measurements and used a spindle gouge for most of the cutting. 8 feet turned and ready for finishing.

The next job was the central pedestals that support the globes. Two are needed, cut from a 600 mm length of 300 mm square redwood beam. The block was only just big enough, I had to cut it in half with a handsaw – it was too big for my bandsaw, and I didn’t think a chainsaw would have cut straight enough even if there was enough length spare for the kerf. Then I used the handsaw to cut off the corners, a total of about 8 feet of sawing. Redwood is quite soft, but seemed to be getting harder as I went on.

The initial sawcut that divided the block left a reasonably flat end grain surface on each piece, on which I could fix a faceplate. On my Graduate lathe, I could drill the axial hole at low speed, then support the block with the tailstock while I shaped the pedestal. I removed some of the surplus wood while still on the faceplate as it gave a very positive drive. Then I switched to my homemade chuck with the tapered insert. When I did so, I found, as expected, that the axial hole was not so axial after all. The auger had wandered a little. On the taper insert, I was able to true it up and continue with the shaping. The redwood is a little soft, and the maximum torque given by the friction was only just enough on a piece this large, so light cuts were essential.

I did not have a pattern for the pedestals, so to some extent I was designing them as I went along. It was very useful  to be able to remove and replace them on the tapers without losing accuracy.

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Sycamore bowls

I recently made a batch of large sycamore bowls from a tree that came from a garden in Kennington. It was a dead tree that had stood for some time, and the wood was quite porous in places. I always look forward to seeing the freshly cut timber surface when a new log comes to my workshop. I was able to make a number of rough-outs that have been drying over the summer. They have beautiful figure and slight spalting. I was pleased with the finished bowls until I oiled them. I found that they soaked up quite a lot of finishing oil and when dry their surface was quite rough to touch. Not only that, there were some pencil lines and scratches still showing – I missed them when sanding before oiling. I must take more care in future!

There is always some degree of roughness after oiling, and usually it comes off when I buff the bowls, but I tried something different this time. I put them back on the lathe and wet sanded them with white spirit and 320 grit paper. A messy job, but they came up silky smooth. Wet sanding with water can raise the grain, but the white mineral spirit did not affect the wood.

There are three in this batch. The two largest are about 375 mm in diameter. They will go on my bowls for sale page later, after further coats of finishing oil.

 

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Carbon steel turning tools

A woodturning student today brought with him some turning tools. He has just bought a second hand lathe and they were included in the deal. They were unbranded, and extremely blunt. We did some sharpening and immediately realised that they were carbon steel.

Carbon steel turning tools nowadays are almost entirely confined to cheap sets sold to beginners. This is not to say they are no use, I still have a number of carbon steel tools that I bought in my early turning days, and more that I have made since. They all work, though I tend to keep most for light duty only. We finished the sharpening and decided to  give them a try in the lesson.

We put a piece of softwood in the lathe and started work with the roughing gouge. After a short time Marc seemed to be struggling a bit. The gouge was bouncing and leaving a poor surface. After more grinding, the same thing happened again. On inspection, I found that the edge was not just blunt, it was bent back, forming a heavy burr. This damage was done by a small knot in the wood. A quick re-grind at a more obtuse bevel angle helped, but it was clear that these tools were not going to be a lot of use. We changed back to my own high speed steel gouges and soon made better progress. I am pleased with how quickly Marc has learned to roll beads with the gouge.

Although they did not appear discoloured, it is possible that the tools had been overheated by their previous owner. If so, it should be possible to grind back to sound metal and give these tools a new lease of life.

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Turning legs for a large globe stand

Today I’ve been turning legs for some large globe stands. I used timber reclaimed from building demolition – some heavy pine beams about 125 mm square. The longest leg sections have to finish at 462 mm long, tapering from 108 mm to 89 mm, with a 12 mm hole down the middle. The hole is for steel tie bars that link the various components of each leg.

Preparing the blanks

The first job was to cut suitable blocks for turning legs from the beams. There was a lot of wastage due to some very large knots which I cut out. I could only use the bits between the knots. I cut them to length, a little oversize, on the bandsaw when possible.But I had to saw some sections by hand, because the saw could not reach to separate the longer sections. As well as the knots, there were some cracks and nail holes, but those were not so much of a problem. The cracks are acceptable in the finished pieces. They are to be used on facsimile antiques, and the nail holes will be filled. I use a metal detector to save the tools.

Drilling the long holes

The axial holes were next. I centre the turning on them later. But with each block about 475 mm long, I have to drill the holes in the lathe. An ordinary drill bit would wander too much, and my drill press has nowhere near enough travel. So I put the blocks in the lathe and turned off the corners to cut down the weight. Then I turned a spigot on one end, dovetailed to suit my lathe chuck.

With the blocks held in the chuck on my Graduate lathe and turning slowly without tailstock support, they looked a little alarming. As long as the speed remained low, they were safe enough. Being unbalanced, too high a speed would have thrown them out of the chuck. I was able to turn a small recess in the middle of the free ends to start the drill, and then go right through with an old cross-handled half-inch auger, held freehand. These augers stay on the axis and don’t wander much, but I find there is usually some drift. You can feel whether the auger is running true and it pulls itself straight at the beginning of the hole. I now had a stack of blanks, each drilled right through, ready for shaping.

Turning legs between centres

I used the taper drive insert that I made recently for my homemade insert chuck. The blanks go between the taper at the headstock end and the conical live tailcentre, so the hole stays central in the finished leg. I used my homemade wooden long tool rest too. At first, the blanks were not running true, because of the drift when drilling. Variations in the grain always send the drill off course a bit and with long blanks like these the error becomes significant.

After truing up the blanks, I trimmed the tailstock end and set the diameter using calipers and a skew chisel. Then I could mark off the finished length and use the chisel to peel away the waste and set the diameter at the headstock end. The next job was to rough down close to finished size, forming the long taper. Turning legs like these is straightforward – the leg sections are simple straight tapers without turned detailing. (I make turned and gilded mouldings separately that go between the tapered and cylindrical components. The legs will be ebonised later.) The only difficulty was getting an acceptable finish. I found the skew caused the grain to pick out, so used my wide, shallow roughing gouge with a fresh edge and light cuts.

The final jobs were to cut off the surplus length on the bandsaw. I cut the stubs of waste flush using my homemade counterbore. This goes in the lathe headstock and by pushing the leg against it with the tailstock the teeth trim off the excess. It makes a bit of smoke but does the trick. Then I fill the nail holes, sand, and they are ready for ebonising.

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Making balls

Today I’ve been making balls. I needed a batch of 75 mm diameter and used the Hercules tool in my heavy duty ball cutting jig. The tip is set at a forward angle on its shaft, so the tip scrapes, giving an adequate finish (the tip is getting blunt now, it’s done a lot of work in the past few days). It happily ploughs through the wood still.

Sanding can easily distort the final shape of the ball, so I tried mounting the Hunter tip horizontally on a cutter bar to give more of a shearing cut. This duplicates the effect of lowering the handle of the Hercules tool. However, the bevel is then almost vertical and there is not much clearance under the edge. This means that although it gives a better finish in this position, only a very small cut can be taken – the bevel stops the edge penetrating freely – and this makes the process too slow.

So I put the tip back on the proper tool and put the whole assembly in the jig. I had to do a little more sanding, keeping it as even as possible, but the job went much quicker, and the long handle is handy for swinging the jig round.

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Hunter Hercules tool

I turn quite a lot of mdf and gritty reclaimed hardwood, both very abrasive and hard on the tools. The mdf turns quite well with HSS or even carbon steel scrapers, but they soon blunt. The gritty timber sometimes strikes sparks from the edge of a steel scraper, and knocks the edge off a gouge after just seconds of cutting. So I have been looking out for a tool that would hold up better. One day I shall try diamond tips – you can get diamond router bits, so perhaps they are available for fitting to woodturning tools, or perhaps a router bit could be adapted. I’ve tried various tungsten carbide scraper tips (though so far not the well-known Easywood tips), but found them to blunt quickly and not cut as well as HSS even when new.

The other day I purchased a Hunter Hercules tool. This has a little round cupped carbide tip set at a forward angle on a very robust, heavy steel shaft with a substantial handle. The tips are silvery-bright polished carbide and when new will catch on your thumbnail as sharp tools should. 

It has three modes of operation. Used with the tool shaft horizontal and flat on the rest, perpendicular to the surface and cutting on the very tip, it gives a semi scraping cut that is quite aggressive. If the handle is twisted and the side of the tip used, it shear scrapes and can give a good finish. It can be used for a bevel rubbing slicing cut that also gives a good finish. 

I tried the tool on some edge-grain mdf. In semi scraping mode, it cut freely for a while before the edge lost its initial keenness. But it kept going. The small tip penetrates easily and whether semi scraping or slicing it keeps on taking off the waste. Even on the mdf face-grain, which with normal scrapers produces shavings, the waste was very dusty indeed. The finish produced was not brilliant, but adequate after a little sanding, and I shall normally make the final cuts with HSS tools anyway. I made several complete components with the tip still going strong.

I found the tool quite catchy when going into a spindle cove in semi scraping mode. To avoid problems, the tool has to be swiveled and the cut kept on the front third of the tip’s circumference, say between 10 and 2 o’clock. The  inclined edge at 9 and 3 tends to catch on the sides of the cove and run back. I found it can catch and run in this mode on a flat surface or a hollow on faceplate work too. The best way to prevent runs when semi scraping is to push rather than pull the tool. The small diameter of the tip means that it is not so easy to get a sweeping, regular curve – the tip penetrates easily so any additional pressure makes a dip in the surface.

It is easy to ride the bevel in a straight line or round a curve. This gives a controllable cut and clean surface just like a gouge, but only light cuts can be taken as the tip is small.

Shear scraping with the Hunter is similar to with a normal scraper, but the small diameter tip makes it a little harder to get an even sweep.

Replacement tips are not cheap, though they may last a long time on easy timber. The maker hopes they will be considered disposable, but I hope it will prove possible to sharpen them. Flat carbide tips can be sharpened on their upper surface with a diamond hone, but this would flatten the top of these cupped tips. I intend to try three alternative methods – hone the top and afterwards use the tip as a normal flat tip scraper; mount the tip on the end of a rod like a dop stick (or just pin it on the end of a rod using the tail centre) and hone the bevel while it spins in the lathe; and hone the groove in the top using a very small diamond ball point in a Dremel, also while spinning the tip. I doubt if any of these will equal the original grind, but  shall report the results in due course.

So I am pleased with the tool so far. Quite impressed.

If it cuts mdf, I’m sure it will cut ordinary wood. I tried roughing down a small oak spindle blank in semi scraping mode and it worked well, though it did leave small feathery shavings not completely severed if traversed too fast, due to the small tip diameter. I have not yet tried it on the gritty stuff but shall update in due course. I have however roughed out a number of boxes in some unknown but hard and very abrasive wood. I have not yet changed or sharpened the cutter, though I have turned it through 180 degrees to a fresh edge, and it is still cutting quite well – HSS would have needed many sharpenings in this time.

It will not replace my gouges and scrapers. I shall use it on difficult materials as a roughing tool, and be grateful for the long edge life. When really blunt, the edge becomes badly chipped and eroded, and then will not give a good finish. No doubt others will use it on more tractable timber and get nice polished surfaces straight off the tool, but for me it is too slow-cutting for routine use – I get on better with normal gouges and scrapers that are more free-cutting.

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Homemade chuck

A common problem facing woodturners is how to hold pieces in the lathe. The usual options, such as faceplates, scroll chucks and spur drive centres deal with almost everything perfectly well. But sooner or later there is something different needed. Often in these cases I use my homemade chuck. This is simply a holder, made of steel and mounted on the lathe spindle nose, into which a variety of special purpose inserts can be fitted.

I often have to turn items with a half inch diameter axial hole. In these cases it is usually best to drill the hole in the blank before the turning is done. If the hole is used as the location for turning, it remains true in the finished item. How to hold it in the lathe so the hole is central? Till now, for larger holes, I have either used a conical tail centre in the headstock to drive by friction, or a counterbore with a pin to locate in the hole. Both are liable to slip on larger pieces.

So I made a taper pin for the insert chuck. I cut a piece of mild steel rod about 2.5 inches long and 5/8 inch in diameter and used my old Atlas metal turning lathe to reduce the diameter to 1/2 inch over part of the length, to fit my insert chuck. Then I reversed it in the lathe and turned a gentle taper, leaving it just under 1/2 inch at the end, so it would slip about 1/4 inch into a 1/2 inch hole.  Then I filed a flat on the shank where the locking screw bites, and the job was done. An insert like this could also be made from a soft steel morse taper with enough length to turn the taper on its nose, a job that could be done by hand in the wood lathe. For light work, it could be made from hardwood.

The taper has to be right, though I haven’t measured it. It’s not really critical, but too steep and it will not grip well enough, too gentle and it can split the wood. A little steeper than a morse taper but not as steep as a tailstock dead centre is about right. If the drive does slip, I can just tighten the tail centre a little more.

I used the chuck to make some wooden cylinders about 4 inches in diameter. Mounted on the taper, with the tail centre to keep them in place, they turned easily and accurately.

Taper insert for homemade chuck

 

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Using Tormek jigs on a high speed grinder

I want to try using Tormek jigs on a high speed grinder, so have been fitting up a new tool rest. I bought a Tormek rest bar and holder that they sell for use on dry grinders. It’s just a bit of welded steel bar and an aluminium clamp for it, a crazy price for what it is. You would think it was part of a NASA rocket. Fitting it was straightforward, I just had to stack up some bits of MDF to get the right height for the clamp.  I fixed the whole assembly next to the dry grinder. I tried various positions and heights on both sides of the grinder. It was important to make sure the jigs cleared the wheel guards and the other tool rest.

I can now use my Tormek jigs on both the dry grinder and the Tormek grinder. It should improve the sharpening of bowl gouges in particular. I find they often need heavier grinding than the Tormek itself is happy with (it can do it, but is fairly slow). I made a couple of setting jigs for the Tormek platform rest. On one setting I can now sharpen my roughing gouge and also my skew chisels. These have a keener grinding angle than the gouge, so I just add a raising block made of MDF.

You can see a review of the Tormek here.