Woodturning Journal June 2006

I didn’t get much turning done in June for one reason or another. At the start of the month I thought the tools were getting a little dull. After turning a spindle I decided that there was no point in continuing without first sharpening the tools. My skill level seemed to be going backwards despite the fact I was getting more practice. I would present a gouge to the wood and rather than nice clean shavings I would get dust and a very hot tool. The roughing gouge was even worse. The left hand side (as one holds the tool) was so blunt it wouldn’t cut at all!

Despite this I did manage to turn the spindle shown below which is one of my favourite pieces so far.
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I wasn’t sure what the best way to sharpen the tools was. At one end there is the oil / wet stone and at the other is a sharpening system such as the Tormek. I read around about sharpening and one thing seemed clear – if the sharpening wasn’t performed well the tool wasn’t nearly as effective. I was pretty sure that hand sharpening on a oil / wet stone was a non-starter. The scope for grinding the tools incorrectly was just too great and I didn’t want to waste my time finding this out and then re-grinding them correctly.

This, as far as I could see, left me with three choices:

  1. Buy a standard grinder and build jigs as described in numerous books.
  2. Buy a standard grinder and jigs.
  3. Buy a complete sharpening system.

The options are listed in price order and, in my opinion, in complexity of use order. The first option is by far the cheapest. A grinder can be picked up for next to nothing these days (although to some extent you will get what you pay for) and the wood and other pieces of equipment necessary to build some simple jigs shouldn’t set you back more than a few pounds. The main cost with this solution is time. It takes time to build the jigs and it takes time to learn how to use them correctly. Even using a rest, sharpening the correct angles on a spindle or bowl gouge is something of an art form.

The second solution is relatively cheap and can be very practical. Jigs can be purchased that will fit, or can be made to fit, most makes and models of grinders. The grinder is mounted on the bench with the jig typically placed in front of it. The user mounts the tool in the jig which then ensures it is ground to the correct angle. There is still some skill involved but it is minimal compared to the skill required when using home made jigs. There are, in fact, only two draw backs to this method of sharpening that I can see.

The first drawback is over heating the tool edge and thus softening it. Most places I have read indicate that if the tool is blued (shows blue streaks around the cutting edge) due to heating the hardness will have been lost and the tool will no longer hold a good edge. I read that the critical temperature for HSS is in the region of 250 deg C which is easily achievable when being a little over zealous on the grinder.

The second problem I can see is that a standard grinder won’t produce a fantastically sharp edge. Most grinders come with a rough and a smooth wheel. The smooth wheel will give a fair edge but it won’t give the razor sharp edge that can be achieved with a whet stone.

The third and final solution is by far and away the most expensive but should also give the best results. A sharpening system will come with a range of well designed and thought out jigs that are designed specifically for the equipment they are being used on. Most sharpening systems use a large vertical water cooled wet stone for primary sharpening and provide a leather wheel for honing. The end result from such as system should be a tool that is razor sharp.

After much thought I decided that I would go for a sharpening system. As I had plumped for a decent lathe I felt it would be silly to try using it with poorly sharpened tools. Back in May I had spoken to a turner at a fare and asked him what he recommended for sharpening tools. Without even having to think about it he said “Tormek”. We got chatting and I pointed out that Tormek systems were quite expensive which he agreed with but indicated that they were worth the money. With that ringing endorsement in mind I went looking for sharpening systems.

After looking around for a fair while it became apparent that Tormek wasn’t the only game in town but they had the market pretty well sewn up. I was apprehensive at spending that much money on something that seemed, to my untrained eye, not to do all that much. After much hand wringing and complaining at the price my partner finally convinced me to buy a Tormek so I started looking around for the best price.

It turned out that D & M Tools actually had the best price as they were running a deal and we could spend the £20 worth of “points” we got when we bought the lathe. At the time they were also selling Tormek systems will sharpening kits which reduced the price further. After pricing up a Tormek 2006 SuperGrind and the nearest competitor there was actually very little price difference which made me feel a little better about splashing that much cash around.

While at the D & M site I decided to have a look at chucks. I pretty much wanted a chuck from day one but I had decided to hold off buying one until I was able to spindle turn at least a little bit. I thought it would be quite a nice present to myself to be freed of the confines of spindle turning.

To cut a long story short D & M were running a special offer on the Record Power RP4000. I had looked at chucks in magazines and adverts and already decided that this was a fairly good chuck. In a moment of unusual decisiveness I added it (and a set of pin jaws) to the shopping basket and checked out.

A couple of days later the kit arrived. As with most stuff from D & M the boxes looked like they had come through a war zone. The box for the sharpener in particular was very badly damaged. It actually looks like the fork of a fork lift truck punctured the box. I checked the machine carefully and it was fine – not so much as a scratch. By shear luck it appears the fork entered a void in the machine and therefore didn’t actually touch it.

I first set up the sharpening system as I couldn’t realistically use the chuck until I had sharp tools. Right from word go I was highly impressed with quality of the Tormek system. The grinding stone is huge and should last for a good length of time. The kit also comes with a DVD to introduce the system and a hard back book telling you exactly how to grind each tool type and which jig to use. Amazingly the book isn’t 100% hard-sell buy Tormek – most of it is quality tool sharpening advice.

The DVD that comes with the system is interesting and well put together. It shows off what the machine can do but it doesn’t teach you how to use the machine – that is left to the book. The first third of the book is sharpening theory, the middle third is on how to sharpen a wide range of tools and the last third is reference material.

I set the sharpener up on the kitchen table (naturally) and grabbed a kitchen knife. I bought the woodturning sharpening kit with the sharpener which doesn’t come with a knife holder so my first bit of sharpening had to be done freehand. In hindsight I am glad I tried freehand sharpening first because it was a real treat to then use one of the jigs. So, I sharpened a knife as well as I could freehand and passed it over to Hazel to do the tomato test on it. A knife is only sharp if it can cut the skin of a tomato without squashing the tomato.

The knife was brought up towards the fresh cherry tomato and the tomato just fell in two through fear – the knife was that sharp. Joking aside it was just like the tomato fell apart. No pressure was needed – the knife was like a scalpel. At that point I couldn’t resist it any more so I grabbed the roughing gouge and started setting up the jig.

Getting the settings right on the sharpener can be fiddly. To set the angle you have to wind the support bar in and out. A tiny change in the position of the support bar causes quite a change in the angle the tool is presented to the stone. Perhaps I was being a little over cautious though as this was my first time. To check that the tool is presented at the correct angle one colours in the bevel of the tool using a permanent marker then rotates the stone a fraction of a turn by hand. If the colour is removed from the whole bevel the angle is set correctly.

The roughing gouge wasn’t very well ground from the factory and was a slightly different angle on each wing. I chose half way and ground the whole tool to that. Steel removal with a wet stone such as this is fairly slow compared to a regular grinder which makes it excellent for keeping tools sharp but poor to reshaping. The book indicates that you can reshape tools on this stone but I’m not convinced – it would take a considerable amount of time.

I then went through and sharpened everything I could lay my hands on. Most of the turning tools were also honed which I initially thought didn’t really do much. I quickly discovered the difference it makes if you get it right – a well honed tool is not only sharper it also holds its edge better.

Now that I had sharp tools again I rushed back to the lathe to try them out. The roughing gouge was the most impressive improvement. It went from being a fight to remove wood to working like a hot knife though butter. The other tools were also a vast improvement even on how they had come from the factory. The only disappointment was one side of the 10mm spindle gouge which still seemed to be blunt even though it looked sharp. I took it back to the sharpener and tried again. Upon re-introducing it to the work it also cut like a knife. I can only assume I missed a patch first time I sharpened it.

I dislike warnings on everyday items as much as the next guy but I think at this point a word of warning is needed. Knives and tools that have been sharpened with this system are very very sharp. That might sound like a really obvious thing to say but both my partner and myself have been caught out by quite how sharp things are how. Most kitchen knives are sharp but if you touch the blade you are unlikely to cut yourself. Knives that come off this system will cut you if you so much as brush against the blade (my thumb is testament to this).

Now that I had sharp tools it was time to try them out. I couldn’t wait to get started so rather than mounting the chuck I stuck a piece of pine between centres and had a crack at it. The piece is shown below. It’s certainly not my best work but the tools were a dream to use.

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It was now time to try out the chuck. I removed the drive centre (hoping it was the last time I’d have to that for a while) and screwed the chuck into place making sure it was on nice and tightly. I cut myself a length of stock and offered it up to the chuck. It didn’t fit. I expanded the jaws out as far as they would go. It still didn’t fit. At this point I was a little disappointed. I wasn’t using large stock and yet it didn’t fit. I decided therefore to try the pin jaws I had bought.

Half an hour later after changing the jaws I found the stock didn’t fit in the pin jaws either. What I did notice though was that the jaws actually opened further than I thought they did. It seems that the mechanism needed a little working in and I was being too careful the first time I opened the jaws. I called it a day not fancying the prospect of changing the jaws back and resolved to do a little research. There is surprisingly little information on-line about woodturning and even less about woodturning using a chuck. Books tend to focus on either the beginner (who often doesn’t use a chuck) or the experienced (who already knows how to use a chuck) woodturner. The chuck itself doesn’t come with an instruction manual either (a little disappointing I think) so the beginner is more than a little stuck unless they get tuition.

I did eventually find one web page that gave me the information I required. Somewhat ironically it was a review for the Record Power RP4000 the exact model I had bought. The important piece of information I picked up was how to grip the wood in the chuck. The first time I had tried not only had I not opened the jaws all the way I had, and I feel stupid admitting it, tried to grip the wood by the corners rather than the flat sides. I don’t know quite what I was thinking and the second I saw the wood clamped by the flat sides it was obvious that was the correct way to do it. I mounted up my bit of wood tightened the chuck and set it spinning.

It was at this point that I learnt a valuable lesson. Make sure the wood is clamped tightly. I wasn’t quite sure how tight I should clamp the wood so I gave it a bit of a squeeze in the jaws and made sure that it didn’t wobble. As I started to rough it down everything seemed fine. The first pass, which is normally the roughest, went without hitch. The second pass was proceeding well until I got to the open end of the wood. Unseen by me was a knot. The first pass must have lifted the knot because as I approached it with the gouge on the second pass it caught and slammed the gouge into the wood. The wood then decided to leave the chuck and lathe behind and make a break for freedom. I ducked and dodged sideways and the wood clattered to the floor behind me. A little shaken I picked up my piece of wood and re-clamped it making sure this time the chuck was done up tight.

I roughed the wood to a cylinder without further incident. Having turned between centres for a few months it felt very strange not to have a tail stock in place but I was pretty sure I would get used to the sensation quickly. What I immediately fell in love with was the simplicity of mounting a work piece. Having to remove the drive centre and bang it into the work piece before every job was becoming tiresome. With a chuck it’s just a matter of turning a key – much simpler and quicker. The only downside of using a chuck and doing spindle turning is that it wastes a little wood each time as you can’t work the wood in the jaws and the jaws are likely to mark the wood that they are clamping.