My first interest in built up turning began by talking to and seeing the work of the late Arthur Carey who was one of our best craftsmen. He produced some really beautiful pieces. The second reason for "having a go" was the article in the Australian Woodworker in the May/June issue in 1992.
I had been looking for something else to do other than the usual run of things (i.e. bowls. Pens, clocks etc.) and when I saw the picture of an urn on the front cover of the magazine, the challenge was on. However, I did not realise at first just how much work was involved or the amount of timber, veneer and glue I would require
The first task was to set out the urn in full size detail
allowing for the maximum swing of the lathe. The next step was to
have pictures of an urn blown up to the full size that I wanted; this
then gave me an elevation view to start with.
Then, taking a pair of compasses, I set out to plan the amount of
pieces required. As Math's was one of my better subjects at school I
decided that with there being 360 degrees in a circle, then 36 was
the number to use with 10 degrees the angle of all my cuts.
Now I was ready to make patterns of the end view of the staves and also the jig required to cut them on the bandsaw. This required a lot of time to make sure that everything was exactly square and parallel. In all, this took me about four hours but the time was well spent as when put to use, it allowed the cuts to be very precise
The timber used was:-
Alder, 15 super feet,
Walnut veneer, 30 square feet,
Meranti, 30 feet of 4" x 3/4"
After machining, there was very little left of what seemed a lot of
material.
I do not believe that a process like this can be achieved with
out a thicknesser. I bought this by selling tools that I no longer
required and had not used since my retirement from boat building and
fitting out. The swap was really well worth while.
The next job was to make a jig to use with the thicknesser. Again,
this work had to be precise to make sure that everything was 10
degrees and all the pieces were the same.
After so much preparation, I was looking forward to putting the urn together. The first stage was to glue veneer to both sides of the mahogany spacers, and then to glue these to one side of the staves. Various jigs were made to cramp them together and reject staves were used as packing to ensure that the glue lines were horizontal. This was to eliminate any chance of pieces sliding out of position. When taken out of the press, they were stacked in pairs and lead weights placed on top to stop them bending, because as we all know, when you glue and fix to one side of a piece of timber, unequal pressures are created and the sections will take the line of least resistance.
The next job was to cut the internal profile. The piece cut out
was then put aside to make the second and third urns.
The assembly of the first urn was a lot easier than the second. This
was because of the square corners still left on the staves which
meant that the staves could stand upright by themselves. I bought two
large circlips from the local plumber supplier; a bit expensive at
$11 each but when put to use, I found that it was the best way to do
the job. They not only exerted a lot of pressure and pulled the
staves into place, they formed a circle with only 1 mm.
tolerances.
After leaving for 24 hours, I dressed one end with the electric
plane. This was to ensure that when reversed and stood on this end,
the sides were vertical all the way around.
I then planed the other end and checked that it was square to the
sides. Two pieces of craftwood were then cut to the size of the
external diameters and the centres were clearly marked for centering
on the lathe. They were then glued to each end and when set up on the
lathe, the barrel (as it now looked like one), was less than 1 mm out
of true. I was very pleased to be as near as this. I was now ready to
begin to turn.
When I was assembling, two of the staves had the outer profile cut nearly through - just leaving sufficient material on the corner to hold while cramping together. This gave a visible depth guide as I turned the outside. Of course, number two and three Urns had the outer profile to start with although this did cause a lot of problems with cramping them together.
The first part to turn was the top end. This was achieved with the use of one tool - a roughing gouge. The shavings came off in a beautiful arch over my shoulder. With the outside profile cut on two of the staves, there was no fear of going too deep. The top end could only be taken just so far as this end had to be fitted with a face plate to allow for reverse centering. The work had to be as precise as possible and took a fair amount of time but was well worth the effort. When I reversed the urn, it was less than .5 mm out of true.
As the base end of the urn was in position next to the tail stock, this was ready to finish off completely. First the outside profile and the piece of craftwood were turned down to give me access to the inside. This was turned out using a long - reach tool made by our member, John Morgan. The tool was excellent for the job.
The inside sanding was done with the handle of a plastic brush which was very flexible and with sanding paper fixed to it with masking tape, it certainly saved me from having to count my fingers!
The base itself was built up with mahogany, white beech and
walnut veneer then turned down to shape and sanded with up to 150
grade sand paper. Final sanding was to be done when the top was
completed.
The next step was to glue a piece of craftwood to the base and then
turn a small recess to allow for the face plate. This was then
screwed in place and the urn reversed in the lathe once more.
A repeat of the base turning was then completed with turning the
inside and sanding.
The neck of the urn was built up in sections, glued into place
one section at a time, and then turned. This was to eliminate any
vibration as I was now working a fair way from the face plate.
The final top section was then turned separately and glued in place.
This left just the outside to finish.
I then proceeded with a final sanding; finishing off by hand sanding
along the grain with 800 wet and dry paper.
The finish that I use is Swedish Oil. At the present moment I have applied eight coats, rubbed down every two or three coats with OOOO steel wool. This is quite a good finish.
The best of luck to any one who undertakes this project, but the end result is well worth the effort.
