Sunday, 25 April 2010

Tapered sliding dovetail joint, tree trail signs

Tree trail signs

I have been commissioned to make signs for a tree trail, so I thought I would make them stand out a bit by not just nailing a plank onto a stick. No metal has been used to hold these signs together, they rely on a dovetail joint.
The wood came from the forest the signs are going into, larch for the posts and Douglas fir for the arrow. I would have liked to have split the wood out of the logs, but in my experience softwood grown in this part of the world does not cleave. A chainsaw was used to rip the logs into quarters.
A dovetail notch was cut an inch or so deep into the post. This was done with an electric chainsaw, with the waste in the middle chiselled out.
The arrow part is just over two inches thick and the joint is chain sawed out, and tidied up with my GB carving axe and a flat chisel. The edges are tidied up with an axe. I did put the face of the arrow onto my jointer (planer) to flatten and smooth it. This is because of the Trend letter template I use to route the letters into the wood.

Fitting the two parts together does not take very long at all, just a bit of shaving with an axe and chisel, and a couple of trial fits. A small hole was bored through the post and arrow from the back and an oak dowel driven through so the sign cannot be taken off.
I wonder how many people will notice how they are made.

This idea came from the European dovetail joint, which I first saw on the Bodgers forum. This is a fantastic joint, which I will be using far more often. Its joy comes from it being self tightening and also it is quick and simple to knock apart, unlike a round mortice and tenon, which can lock tight.

 Above is a photo of my bowl lathe made with the tapered dovetail joint, and below is the leg taken out. All that is needed to make this joint is a chisel and axe, although a saw will speed things up.
I have used an inch-and-something diameter augers to bore holes into my chopping blocks, benches etc.,but sometimes when I need to take them apart for storage or transport, the tenon leg gets stuck in the hole, especially at the end of a show when packing up the van. The round mortice and tenon is great for fixed joints, but not so clever for joints that need quick dismantling.

Monday, 19 April 2010

Rip sawing

Rip Saw

Today I sawed my first plank of wood with a saw I refurbished myself, again bought for a couple of quid and in a rusty condition. This saw is a rip saw, made for cutting along the grain.

The saw blade is 26 inches long and the willow I cut was 9 inches wide, it did take a while to cut. The plank also got a little thin at the bottom end and it is difficult to work out why. Was it my technique or was it because of the how I set and sharpened the saw? I did change the sides I sawed on now and again, and a slight bow across the cut can be seen. For a saw only 26 inches long I think sawing through a 9 inch plank could be a bit too much.

Detail of the rip saw teeth

I have nearly got a full complement of saws, and will never have to buy another plastic handled hard point saw again. There is something very satisfying about being able to set and sharpen my own saws, a self reliance which is empowering.
The old saying goes that the blacksmith is the king of all trades; this is because they are the tool makers. I would love to be able to make my own saw one day, but then again I will have to learn the craft of making files as well.
Here is a video of a craftsman making a saw in Japan. 
If  you have an interest in Japanese tool making do watch the other videos Noko, Kanna and Genno.

This link was posted on the Bodgers forum, by Dave Budd. If you have an interest in green woodwork, you will love this forum.

Thursday, 8 April 2010

Scots pine and fan birds

Scots pine

I now have a year's source of wood for making fan birds - actually, it is probably more than ayears worth - it depends on how many I make and how many workshops I run.
The Forestry Commission at Haldon, Exeter let me have a Scots Pine tree. Ian Parsons (one of the rangers) and I choose the tree, straight grained and slow grown. This particular area was planted with Scots pine, and unfortunately the soil is not good so the trees never grew very fast, and do not have any real commercial value. They were planted in 1926ish, the biggest trees are about 14 inch diameter and the smallest are 5 to 6 inch diameter.

I like Scots pine, a native to this country; and not too resinous, unlike some of the other softwoods. It works very well green or dry and I have made small spoons from it in the past. I will also give it a go on the pole lathe and see if it makes a decent bowl.

The tree was felled at about 9.30am and by 11 am I had made my first fan bird from it. Some woods need to be mellowed or dried out a bit before use, but not this one.

I think this one tree could potentially make around 400 fan birds, and at an average of £20 each - that is good value from a tree that has a commercial value of £0 to £2 a cubic foot. It is interesting that for a maker, one tree might yield so much potential income.
Before you start rushing out booking onto my courses or just learning how to make fan birds, so you can make your fortune, there are a few things to remember. It is fine to make a whole batch of items but then you will need to sell them and that takes time and money. A certain amount of the stock can and will get damaged, especially with fan birds; and some will just fail as you make them - but that can be less with the more experience you have. Then there's all the fixed costs: workshop rent, insurance, van, etc. And the value of the time that it takes.

I would be interested in how other people can add value to trees. Unfortunately it is not the grower who gets much money for the wood as our forestry industry is depressed. The green woodworker is not a great consumer of wood and can make a little go quite a long way. We also can use wood that would be considered fire wood, thereby adding value to it. However, a lot of foresters do not really want to sell odd bits of wood to the occasional green woody: they want to sell it by the lorry load.