Category: Tool reviews

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Tormek review – Is this the best machine for sharpening woodturning tools?

The Tormek is one of the best machines available for sharpening woodturning tools. It has a slow-running wet grinding wheel and a honing/stropping wheel. It comes with many optional accessories. I have the ‘Supergrind  2000’ model – newer models may differ. For a long time I used the machine for sharpening my spindle gouges.

I don’t recommend the Tormek special woodturning kit if you also have a high speed grinder. It includes things that you will probably use only rarely, if at all.  The accessories I use are the adjustable gouge jig shown below, and sometimes the small stropping wheel for gouge flutes. I use the large stropping wheel for bevels.

Tormek review

The Tormek is robust, quiet and generally well-made. It does a great job, giving an edge straight off the grinding wheel that is a pleasure to use. The grind is accurate and consistent. If heavy grinding is not needed and you keep the jigs set up for a single bevel angle and shape, the Tormek is quick and easy to use. It will also sharpen bowl gouges very well. So far, so good.

I find that I often have to take more metal off a bowl gouge to restore the edge than I do with a spindle gouge. That’s because the greater diameter of the wood and larger amount of waste to remove means the tool has more work to do. Also, the bowl gouge is often used with a scraping or semi-scraping action. Bowl blanks are often log sections with bark, and usually have grit in or on them. In addition, we tend to tolerate blunt gouges until the final cuts on a bowl. Having to grind for longer to restore the edge makes the Tormek slower than a high-speed dry grinder set up with a bowl gouge jig. I have such a grinder and find that I prefer that for my bowl gouges. Similarly with scrapers, which are sharpened very frequently. A dry grinder is fine for those.

Minor problems

The Tormek is expensive for what is really a very simple machine. Its performance is in some ways disappointing, with a number of minor problems:

The drive slips. When the machine has been used for a while, pressure on the grinding wheel begins to make it slow down and stop. This gradually gets worse until it becomes a problem. It is easily remedied by cleaning with abrasive the rubber friction wheel on which the motor spindle bears. Then it starts gradually getting worse again. The friction drive is an extremely simple way to get the very low speed. But I can’t help thinking that there should be a better arrangement with a more positive drive.

The stone wheel

The stone wheel wears rapidly, and is strangely expensive to replace. Harder wheels are available, including diamond faced ones, at an even higher price. If you use a Tormek for gouges, especially bowl gouges, you have to keep them moving across the grinding surface to spread the wear. Even so, the wheel will soon develop grooves, and is then harder to use for flat tools such as chisels. You can still sharpen them by sliding the tool sideways so the high spots of the wheel do all the work. Indeed, this will tend to correct the uneven wear. If a flat tool remains still, its edge will be ground unevenly and will not be straight. You can buy a diamond tipped tool for truing the surface. The old model truing tool I have is not easy to use, because the slow speed of the wheel makes the diamond cut a spiral on the wheel unless it traverses very slowly. And of course, each time you use it the wheel gets smaller. I sometimes use one of the diamond matrix dressers sold for high-speed dry grinders, using it freehand. Its wide contact area prevents the spiral grooves forming. The Tormek ‘stone grader’ block is used to dress the wheel, but soon wears hollow and begins to lose its accuracy, and of course it makes the wheel smaller each time it is used. I have not found the stone grader useful.

Gouge jig

To set the gouge jig to the angle required needs an Allen key. A thumb screw or wing nut would be more convenient. But if you normally leave it at the same setting, the key is not a problem.

The swiveling gouge jig has plastic bushes that slide on the tool rest bar. They are not secure in the jig, and can fall out and get lost, though in fairness I should say that this has only happened once on mine (so far).

This jig clamps over the gouge flute. It has a brass disc that bridges the side wings and a small brass peg that goes into the flute. When the flute gets shorter, the peg starts to contact the flute bottom where it curves up at the handle end, and the jig loses its grip on the gouge. This can affect the grinding angle because it allows the gouge to slip backwards if you don’t notice it is loose. You can  grind a flat on the tool for the jig to clamp on, and extend and deepen the flute, letting you carry on grinding short tools, but the grip is not as secure and the self-alignment is lost.

 

The motor is not reversible. Making it so would remove the need for two tool rest bars. And the motor is single speed. Variable speed would make the machine more versatile. These are common features in many electric tools now.

The water trough is a little awkward to take on and off, and easy to spill, so you may need to stand the machine in a tray.

Bearings

There are reports that the bearings suffer from rapid wear and corrosion. I have not found this on my machine yet.

Stropping

After grinding, you can strop the tool on the leather wheel. But you first have to re-set the jig. This is because the two wheels are not the same size. The obvious answer, making the honing wheel bigger, would not solve this problem as the grinding wheel soon wears down. If you grind with the wheel running towards the tool edge, you will have to turn the machine round and move the tool bar to use the honing wheel. And only one tool bar is supplied as standard, so it has to be reset each time it is moved. Usually I skip the power stropping, though sometimes I use a hand-held leather strop. With care, you can strop tools on the Tormek freehand, and it gives a really sharp edge. But it is easy to dub the edge over. The edge straight from the grinding wheel is very good for turning tools.

Wet grinding

One of the main selling points of the Tormek is the water bath for the grinding wheel. I find that the water evaporates quickly. Rather than have the wheel clog up with salts from our hard tap water, I use rainwater from a butt next to the workshop. Carbon steel is easily overheated on a high-speed dry grinder if you are heavy-handed. It turns blue at the edge and loses its temper. The tool is not ruined, but that part of the edge will not stay sharp very long. The Tormek will not blue the edge, because of the water flowing over the tool, and because the stone turns slowly. But with care, a high-speed dry grinder will not blue the steel either. You just have to keep the wheel clean, keep the tool moving, and avoid pressure and dwelling on one spot too long.

When I started turning, many years ago now, carbon steel tools were the norm, and modern grinding jigs were not available. I learned to grind them freehand on a high-speed grinder with long-lasting hard grey wheels. Almost all turning tools now sold are high-speed steel. This is very resistant to heat, and will not lose its temper in grinding.

So it seems to me that the principle feature of the Tormek is not really essential, for turning tools at least. The water does carry away the grinding dust. Without water, the dust would cling to the cutting edge, because steel tools often become magnetised. The water keeps the grinding wheel clean too. Using water could be a problem if it freezes.

Jigs

I normally use only the gouge jig, keeping it set for my spindle gouges. It is easy to make setting blocks for it, with different angles to suit different gouges. Then you just have to slacken the screw, lay the jig on the block, and re-tighten. I also use this jig and the platform jig on my high speed grinder which I have set up with a Tormek tool rest bar.

You can also make a stop block to get the gouge projection the same each time, one to set the tool rest bar position, and another to set the position of the height adjustment clamp (though I never change this). These setting jigs (or simply not changing the settings at all) are the key to getting a quick result from any grinder. The one below for setting the gouge jig has two different angles, one side for bowl gouges and the other for spindle gouges.

Tormek setting block
Tormek setting block

Sharpening woodturning tools

The Tormek puts an extremely good edge on turning tools, and being slow running, it is easy to use for a beginner – you’re less likely to accidentally grind away too much metal in the wrong spot, though even with the jigs it is still possible to end up with the wrong shape. With setting blocks, it is quick to set up, and quick to use for sharpening. It will not burn the tool edges. Tools become really sharp, a pleasure to use.

However, it is very expensive. Grinding is painfully slow if re-shaping a tool. You have to maintain the wheel and the drive. And you have to top up the water bath often, and clean it.

Dry grinding

It is perfectly possible to sharpen turning tools, including spindle gouges, with just an ordinary high-speed dry grinder. You can do it freehand or with simple jigs that can be homemade if necessary. The tools will not have as good an edge as the Tormek gives. But they will be sharp enough for good work.

Both machines are useful and I like having both. But if I had to choose between my Tormek and my high speed grinder, I would keep the latter. If you want to do more than just sharpening, the high speed machine is more versatile. And you can always use a diamond stone to hone the edges after grinding. And you can strop them with polishing compound on a bit of leather glued to a strip of wood. This can give an edge as good as the Tormek. Here is a post on using Tormek jigs with a high speed grinder

There – perhaps this Tormek review has just saved you some money!

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Graduate lathe, a great machine for bowls, though not without faults.

The Graduate lathe was designed in consultation with Frank Pain, one of the first turners to write for the amateur. He was a professional of very long experience and knew a thing or two about lathes and woodturning.

I bought my Graduate lathe many years ago. At the time it had little competition. It was perhaps the most solidly built machine available for non-industrial use, and the lathe you bought if you wanted the best. It was intended primarily for use in schools, back when schools taught woodwork, although my own first turning experience at school was on a Myford. Ray Key, another well known turner, described the Graduate as being ‘head and shoulders above the rest’.

This lathe comes in a long bed and a short bed format. Mine is a short bed, better for bowls and boxes because it takes a larger diameter and you can stand in front of the work without bending. It can be used for spindle turning, though not very convenient for this, and the maximum workpiece length is short. I have now bought a larger machine, but happily used this lathe for bowls and any larger work. It was a great improvement over the small spindle lathe that I owned at the time.

One problem with the Graduate lathe is that its centre height is low. Most people would want to raise the height. I had a welded triangular platform standing on steel pillars made for mine. This brought the centres up to elbow height, which is the normal standard. It also increased the footprint a little, making it more stable. I have not found it necessary to bolt the machine to the floor.

It came with a 3/4 horsepower motor and 4 pulley speeds with a range from 425 to 2250 rpm. This was not suitable for the large discs that I later began making for globe stands, which needed more power and a lower speed. I therefore upgraded with a bigger motor and a Variturn variable speed drive and had a special large steel faceplate made for these jobs. This goes on the left hand end of the spindle and allowed me to turn discs of over a metre in diameter. I installed the Variturn kit myself. It’s a great addition, quiet and smooth, but the lathe still lacks power for very large work. It copes with large bowls, but I prefer a 2 or 3 HP motor to let me work faster.

Although the Graduate lathe was a great machine in its day, and performed very well for most of my work, it has some weaknesses. The shortbed version seems to have been a design afterthought. For all its good points, its design leads to some problems.

The strange tailstock causes some problems. It is not used on the long bed machine. I didn’t often use the tailstock, so the problems I describe below rarely caused much inconvenience in practice.

The curve of the tailstock casting increases the distance between the centres. It is partly hollow, being open at the back. This causes lack of rigidity, and you can sometimes see it flexing as the work turns. The tailstock position sometimes falls where the two bed slots join at right angles to each other. In this position it is not properly supported. Both the foot of the casting and the locking plate below the bed are too small to bridge the slots at this point – an obvious flaw. You can see this in the photo below. I used an extra-large washer below the bed to help bridge the gap.

Graduate shortbed lathe
Graduate shortbed lathe showing unusual tailstock and crossed slots in bed.

The curved casting has its foot closer to the headstock casting than its centre point. This means that when you want the point close to the headstock the locking lever below the bed will not turn. The headstock casting obstructs it. This means that you can’t always give a shallow bowl blank on a faceplate tailstock support. You can’t pin a disc against a faceplate with the tailstock.

The tailstock ram is just a screw (hollow, to take a No. 2 Morse taper) with a cross hole for a tommy bar to advance and retract. I made a winding handle to use instead of a tommy bar. The alignment of the screw on my lathe is not good. The upper part of the tailstock twists in the casting. A pin locks it, and there is enough play to throw the centre slightly out of true.

The toolrest holder casting is also curved and hollow, as shown in the photo. You can mount it in either of the two slots in the bed, with the same problem at the point where the slots meet. I find however that it is normally set in the cross slot clear of the junction. When the tailstock is in place, the feet of the two castings and their locking levers below the bed can sometimes get in each other’s way.

The tool rest holder also lacks rigidity to some extent. The foot of the casting is not directly under the tool rest stem, which allows slight flexing. The holder can slide along the bed slots and swivel, which ought to give free movement of the rest. But as it swivels, there are times when you cannot put the rest in the right position. and the toolrest locking handle, which is another tommy bar, can foul a large workpiece. With the tailstock removed, which is how I usually have it, the toolrest holder has more freedom of movement and there is rarely a problem in practice. The rests themselves are excellent for faceplate work – rigid, and with a good slope and narrow top. They are not so good for spindle work if you like an underhand grip with a finger behind the rest.

The headstock consists of a single iron casting from floor level up. The shell is heavy and robust, with a thin wall. Bolts attach the cantilevered beds to it.

The lathe came with an outboard bowl turning bed on the left of the headstock. But the inner and outer beds are the same height, so there is no more capacity when using the left hand bed on the short bed model. You cannot use the tailstock outboard. The spindle rotation originally was fixed (now reversible with the Variturn), so the threads are different and accessories aren’t interchangeable. Turning on the outboard side is in the reverse direction to the normal anticlockwise. Left-handed turners might like this. It can make some cuts easier, for example when hollowing bowls.

The outboard spindle thread is the opposite hand to the inner side. Because of this, if you reverse the rotation, the chuck is likely to unscrew. But the outboard bed is at least a convenient handle when moving the lathe. It would be useful for large diameter work when attached to the long bed lathe.

With the inboard bed removed, you can turn large pieces inboard. The limiting factor is when the headstock casting gets in the way. It bulges out half way down to accommodate the motor. Without the bed, a free-standing toolrest is essential.

With the left hand bed removed, you can turn even larger pieces outboard. I have used my Graduate lathe to turn built-up oak discs of 60 x 1100 mm. The lack of power was a problem though.

Both beds come off easily by removing the fixing bolts. There are dowels to align the beds accurately when replacing them. One person can do this with the help of a temporary wooden prop to help support the weight during this process. Some people set up a disc sander on the outboard side. The bed is then useful to carry the sanding table.

Conclusion

No lathe is perfect. The Graduate lathe in its short bed version is in some ways a poorly designed and under-powered machine. But because of its mostly great build quality the lathe performs very well and can do excellent work. Any of these bowls could have been made on the Graduate. You may sometimes come up against its eccentricities. But it is usually a delight to use and a Graduate lathe is still a good buy. It’s far superior to most of the cheap lathes on sale now. I used mine for many years and was always able to find a way to overcome its limitations. I have never used the long bed version, which has a more traditional toolrest support and tailstock. It should be excellent for spindle work, though limited for bowl turning.

 

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CBN grinding wheel for sharpening woodturning tools

CBN (cubic boron nitride) grinding wheels have advantages for grinding woodturning tools. They are the latest must-have kit. Unlike conventional wheels, they don’t require dressing to clean and true them, so make less dust, and they don’t wear down to a smaller diameter. They are said to be very long-lasting. This means that any jigs used with them never need adjusting after initial set-up. They have a thin layer of grit on a heavy steel or aluminium wheel. They can be made with very fine grit (though these seem to be harder to find in the UK) and produce an excellent sharp edge on the tools. They are suitable for high speed steel and hardened carbon steel, but unhardened steel may clog them.

I recently invested in a 180 grit 200 x 40 mm CBN wheel from Optigrind and installed it on my VEM grinder, which though old is a reasonably good quality machine. Some small burrs from the old wheel flanges made them too tight for the new wheel. Holding the flanges in my woodturning chuck, I skimmed the bushing parts very lightly with a graver. They would have gone in as they were, but perhaps never come out again!

Update – I have now fitted a new wheel from Axminster. It runs true enough. But not all grinders are suitable for CBN wheels. Mine has large machined wheel flanges with keys in the shaft and labyrinths to keep dust out. The flanges don’t fit the wheels properly, and replacements of the right size and shape and with a slot for the key would be hard to find.

Wheel shroud

I was able to keep the wheel shroud in place. People say that CBN wheels are inherently safe. They say you don’t need to guard them because, being metal, they cannot burst. But this ignores the possibility of entanglement in the spinning wheel. It could catch long hair or loose clothing. Of course, those are dangerous around the lathe too. An unenclosed wheel seems likely to disperse grinding dust more widely, and because they take a long time to stop, they may come into contact with something while still spinning. So it’s best to keep them enclosed.

The wheel runs fairly true, but not as true as I hoped. There is some vibration. I don’t know if the problem is in the wheel or my grinder. The abrasive layer is very thin, so you can’t true it up with a diamond dressing tool. I found also that the grinding surface has some visible ridges and grooves. Not enough to significantly affect the grinding, but a little disappointing.

CBN wheels are aggressive when new

In use, the new wheel is fierce. I understand this is normal, and am expecting it to settle down as the grit begins to wear, but when sharpening a gouge I could see it shrinking before my eyes. It quickly re-ground a heavy scraper. The tools were sharp after this, but I can’t say they were sharper than the old ruby wheel achieved. Some people recommend a coarser 80 grit wheel, but I think that would be too aggressive for sharpening. I would rather take it slower when reshaping a tool and have a more gentle and controllable grind when sharpening. The wheel creates fewer sparks than the old wheel, which might make it a little harder to judge when the grinding is complete. But as the jigs are accurate, a single pass over the wheel is normally enough.

Wide wheels

The CBN wheel is wider than the old one. This makes grinding easier as there is less tendency for careless use to allow a gouge held in a grinding jig to fall off the side. But it does make the wheel heavier, so slower to wind up to speed and slower to stop. In one way, this is helpful as I can sharpen small tools as the grinder is slowing down. It’s then the equivalent of a slow-speed machine (my grinder runs at high speed).

It’s nice not to have to dress the wheel to keep it clean. I hope that when the wheel is ‘run in’ and becomes less aggressive, it will be easier to use. UPDATE: The wheel has indeed become less aggressive and now I wish it worked quicker. But for sharpening, it’s fine. I still don’t notice that it gives a better edge than the stone wheel. I have a blue wheel on the other end of the machine and use that for gouges. I do think a CBN wheel needs to go on a good quality grinder, because it’s hard to eliminate any runout there may be.

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Alan Lacer skew

I am always looking for something new, and recently bought a pair of Alan Lacer skews, the large and the small, and have been trying them out. This is a review of the tools.

I taught myself to use a skew chisel very early in my turning career and have worked with various styles of chisel, wide and narrow, thick and thin, carbon steel and high speed steel, manufactured and homemade, curved and straight edged. All have worked well, but though my favourite has changed from time to time, the one I keep picking up for smaller spindles, and also for scraping details of faceplate work, is converted from a beading and parting tool, with a square section of about 10 mm. Sometimes I have favoured a Richard Raffan-style curved edge, other times a straight edge, which is easier to hone.

In the beginning I would cut beads by planing with the edge of the chisel. Later I changed to using the short point, and finally, on softer wood, to the long point. I think you can get used to any tool with practice. The key requirements of a skew chisel are reasonable rigidity, well-ground bevels and a sharp edge and points.

My first impression of the Lacer skews was that a bit more blade and a bit less handle would have been nice. But the steel is generously thick and heavy, which is important for larger spindles, helping to avoid blade flutter and vibration. This is why I like my square section chisel. The Lacer bevels are long, which I like, and that makes honing easier. The cutting edges were not ready to use as supplied, but a little honing soon sharpened them up. The handles supplied are very substantial, too fat for my hands, though of course yours may be different. I removed the handles and turned them a bit thinner. In any case, it is only laziness that made me buy the tools with handles, I could have made my own.

The tools have one long side rounded nicely and the other left square. The arrises on the square side are rounded over a little with the intention to help them slide on the tool rest. This is very important, and if your chisels don’t slide freely, soften the arrises yourself before trying to use them again. The Lacer chisel arrises were not very well rounded and did not slide properly. A few minutes with a coarse and a fine diamond hone improved things. Wax on the tool rest helps too. I wish lathe makers could find a durable low friction material for toolrests.

The Lacer cutting edge has a very pronounced curve in the middle, almost a hump really. The edge at the long point starts at 90 degrees to the blade. By the time it gets to the short point it is nearly parallel to the side of the blade. The long point and the adjacent cutting edge have no skew angle at all. The short point is very obtuse, and the cutting edge close to it acts more like a knife than a chisel. The ‘hump’ in the middle projects a lot, though of course it is just part of the curve, not separate. With the chisel flat on the rest and the handle down, the hump can be used very effectively to rough down a spindle from the square. I’ve never been a great fan of skew chisel roughing though, as the tool must be kept very sharp for its other functions and roughing can put a lot of wear on the edge.

For me, the shape of the edge is going to take some getting used to. Before buying, I half intended to re-grind the tools to a more traditional shape. I wanted a couple of heavy-section wide bladed tools and thought that these would do even if they had to be reshaped. But they suit Mr Lacer, so I shall give them a fair trial before changing them.

I am finding that the short point is too obtuse for cutting on the point, making for poor visibility. This limits the tool somewhat. The short end of the curved edge is OK for planing a cylinder or rounding over a bead, but I’m not yet convinced that it’s better than the traditional. A ‘knife’-like edge does help avoid dig-ins though.

The non-skewed part of the edge can be used like a straight chisel, which works nicely for simple planing of cylinders or tapers. Long point down helps prevent digging in.

The long point cuts nicely round a curve. The weight of the tool helps stabilize it, though it will take a bit of time before I get used to the weight. Some might find it too heavy, and the tool might be a bit too big for use on a smaller lathe. The thickness of the blade also means that the bevel is very long and this means more time at the grinder. Visibility using the long point is good. It leaves a nice polished surface as you would expect. But the lack of any skewing at the point means the blade needs to be twisted away from the wood when squaring off end grain. Normally with a skew chisel, if it is held upright on its long edge, the skew angle automatically gives clearance to stop the edge touching the end grain.

So I conclude that these are excellent tools, heavy and workmanlike, needing a little tuning up (but that could apply to others on the market too). The Alan Lacer grind is not essential to the use of a skew chisel. Other well-known turners have their own preferred signature tools. Any heavy-section blade can be ground to the Lacer profile, and that profile can be changed if necessary.

Here is another post about Alan Lacer skews.