Copyright © 2019 Burnham-
Whenever a demonstration is performed it is normal that the demonstrator will have tested the demonstration beforehand to ensure that firstly the process works and secondly that appropriate learning points can be passed on to the audience. George admitted that tonights meeting would not be a demonstration but rather a mutual learning experience as he would be attempting “inside out” turning for the first time without any prior experience other than having watched a YouTube video.
The overwhelming majority of the audience were in the same position so first of all George explained the basic principles starting with 4 precisely cut pieces of spindle glued together with a paper inserts. It is vital that the 4 pieces are cut accurately using a planer thickeniser or a band saw with a fine blade as the pieces have to be repositioned and glued into their final positions at a later stage of the process.
Top Tip 1 -
The block was mounted on the lathe using a stebcentre in the headstock to assist keeping the 4 pieces together and a cup centre in the tailstock. The piece was then turned to round whilst leaving of the order of 1 to 2ins of square on the ends to ensure the piece remained intact.
The composite spindle was then shaped ensuring that the cuts were not so deep that they would penetrate the join between the pieces.
After sanding and removing from the lathe, the composite spindle was split and pieces reassembled and glued in order with the cutout shapes now on the inside and set aside for the glue to harden. The end arrows should now all be pointing to the outer corners.
The new composite spindle was now remounted in the lathe and for safety a spiggot was cut on one end and then the piece turned to round …
Top Tip 2 -
… and then the shaping continued to create thin walls to match the inside shape.
Bearing in mind that it was the principles that were being demonstrated, without worrying about the design, we all got a very good appreciation of the techniques involved and I am sure that many of the audience will have been inspired to add inside out turning to their future turnings.
Our thanks to George for a very brave and informative “demonstration”.
To complete the evening George demonstrated turning a bowl out of one half of a bowling pin. The unfinished demonstration piece certainly makes for an interesting design.
Top Tip 3 -