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I've been very busy recently which has meant that my turning and this journal has suffered. Hopefully I will find the time to fill in the missing months as I have numerous pictures and notes. As a quick update on what I was doing in those months I spent them preparing my competition piece for the Woodturning Magazine annual competition. After completing that mammoth task, which was due for October 31st, I must admit to feeling less than enthusiastic about stepping back up to the lathe. I also felt temporarily drained of ideas for things to make. I have been finding that a lack of decent wood is really limiting my turning and I have vowed to purchase wood in the new year.
If you have been reading this journal before you probably know that I have an entire sweet chestnut tree to turn my way though. The problem is that I have no way of obtaining reasonable sized pieces of wood from the logs and many of the logs are split as they haven't been correctly dried. I also have a good supply of pine which I will say more about later.
I didn't do much turning at the start of the month as I really was too busy and lacked motivation. Fortunately, one of Hazels colleagues required some small knobs for her kitchen cabinets. She had seen the competition piece and a saucepan knob I had made and wondered if I could make the knobs she required. I said I would see what I could do. I turned out a sample which she loved and so she asked me to make some more. The initial request was for eleven, I think, which by the end of the job had risen to twenty.
I must admit that they weren't my best work but they were fairly good. Getting the curve on the knobs the same was difficult but I think this will be hard to spot as they are well below eye level. I turned the knobs from pine and did the work for free. I won't be making a habit of doing turning for free but in this case it was something to do and the pine only cost about ã1.
It's always good to try and learn something when doing a job and I learnt quite a bit while making the knobs. Firstly I learnt that it is very hard to replicate a curve by eye. I had callipers and dividers set for the size but I didn't make a template for the curve. With practice I think I could do a lot better but even so a template would be useful. Secondly I learnt that knots can be very dangerous as I had not one but two pieces of wood leave the lathe.
The first piece of wood to leave the lathe was far and away the worst accident I have had and made me rethink my turning. I admit that I was starting to become a little cavalier in my turning, spurred on by my success with the competition piece. The difference, however, was that the sweet chestnut was essentially defect free whereas the pine I was making the knobs from has knots every few centimetres. I gripped a square length of pine in the chuck and began to rough it to round. It was only a short length and I had done this before (although I now believe this to be a fairly dangerous practice in general). The problem was that this time I wasn't paying attention and I placed a large knot at the end of the piece of wood.
I had roughed the piece to almost round when disaster struck. The gouge caught on the knot at the end and the piece came free from the lathe and shot straight up. It took a chip out of the ceiling before hitting the tool rest and then coming to rest on the floor. It didn't hit me but I am confident it would have hurt considerably if it had. The piece hit the tool rest with sufficient force to put a substantial dent in it so it was still travelling fairly quickly even after one rebound. At that point I gave up turning for the evening to have a good think. I decided to never rough down in this manner without tail stock support.
Stupidly, the second piece to come off the lathe was almost the same mistake. I roughed the piece round between centres and cut a spigot for the chuck (the first piece didn't have a spigot). I mounted the piece in the chuck and started sizing it in. All was going well until a small but very dense knot caught the roughing gouge. Since the piece was held by a spigot it came off the lathe far more sedately and, although it hit me, did no damage. As this had happened twice in quick succession I decided to examine why it had happened.
I had burnt the first piece of wood in disgust at my lack of common sense and skill but I had a quick look at it before burning it. I noticed that the dig in appeared to have happened after the tool had passed over the knot. Examining the second piece showed the same pattern - the dig in appeared to be after the tool had passed the knot. Closer examination showed that the small knot had fractured on the dig in side. After thinking about it I suspect what happens is that the knot causes the tool to rise or bounce up as it passes over as it is substantially harder than the surrounding wood. The tool then sinks back in on the far side of the knot but deeper than intended creating a dip. Over a number of passes this bounce gets worse and worse until eventually the drop on the far side is enough to cause a dig in. An alternative theory is that the knot is brittle and shatters when it is being cut. The tool drops down into the shattered knot and tries to take a massively deep cut. The send piece was probably a combination of these two failure modes.
I have tried to think of ways to avoid this problem but have come up with few sure fire solutions. Having very sharp tools helps greatly. This would make sense if the problem is caused by the first theory above as a sharp tool would be able to cut through the knot and be less inclined to rise up over it or bounce off it. I also find that the cutting angle is important. As a relative newcomer still it is easy to drift away from the optimal bevel rubbing cutting position. Taking more care to maintain full bevel rubbing really helps.
Some good came from these accidents though. It has, as I said, made me re-examine my turning. I sharpened all my tools to the highest level taking care to make sure all the angles and edges were good and I slowed my turning down. I roughed down a piece of practice pine and, thinking about what I was doing the whole time, turned beads along it's length. I was amazed at the quality of the beads produced and was doubly amazed because they were turned with the short point of a small skew. In fact the beads were of sufficient quality that if the piece were being painted they wouldn't require sanding. I chose beads as I feel they are about the hardest shape to produce.
I also visited the D & M Tools Show at Kempton Park this month. It's the first woodworking specific tool show that I have visited and I am really pleased that I went. I will write a full review of the show in the near future but I have to praise Record Power for excellent customer service. While making the competition piece my roughing gouge snapped at the tang. I have been meaning to contact D & M to try and get a replacement as the tool actually broke when I wasn't even using it. I didn't think my chance of getting a replacement was great but it was worth a try.
I didn't take the tool along to the show but I was interested to know why it had broken and if this was a common occurrence. The salesman at the show told me I should have brought it along as he would have replaced it there and then. He then described why it broke - the steel is hardened all the way up which can sometimes make the tang brittle. He then asked where we were from and when I told him Southampton there was a sucking of teeth and a muttering that they don't have anyone near there. At which point he grabbed a roughing gouge off the shelf, stuck it in a bag and handed it to me asking me to send the broken one back or hand it in to a (fairly) local company they have dealings with. I have never had such great service off a company before and I hope as that as Record Power grow they continue to trust their customers as much.
Woodturning Journal - November 2006 Part 2