Copyright © 2019 Burnham-
Pauls’s demonstration of the use of pewter in woodturning was a first for all the attendees, INCLUDING GEORGE!
The pewter used was Britannia pewter (known as casting pewter), an alloy of predominately tin with copper and antimony costing about £25 /Kg.
Pewter melts at 230C and to maintain the pewter at its melting point Paul uses and electric heater with thermostat control rather than, say, a camping stove. (Heaters available from Henry Krank)
Top Tip 1 -
The objective of the first demo was to form a pewter rim to a bowl. Firstly, using a bowl blank of purple heart wood, Paul shaped the outside of the bowl in order to get the dimensions for the casting of the pewter ring. This is made by cutting a slot (according to the required depth of rim) in a thin blank of suitable close grained wood taking the diameter from the earlier formed bowl blank.
Now carefully pour pewter into the slot and then don’t move it until the pewter is fully set otherwise some crystallisation can take place.
The thin blank is then mounted on the lathe and the front face of the pewter flattened off before cutting a 2mm slot. The pewter ring is then released by carefully cutting the wood on the inside of the ring.
The original bowl blank was remounted using the spigot and the front face flattened off, and then the inside and outside diameter of the pewter ring marked. Using a homemade parting tool with a 2mm slot a tenon was cut to ensure that the top of the tenon was level in order to sit accurately into the slot in the pewter ring. The pewter ring was then glued to the bowl blank using thin superglue and allowed to set.
The inside of the bowl was turned in the conventional way -
Top Tip 2 -
Top Tip 3 -
Top Tip 4 -
The second part of the demonstration showed the casting of threaded pewter inserts in order to connect the two halves of a box. Previously made waxed box wood templates were used to create moulds using a silicon moulding compound called Silcotin HB available from www.greatart.co.uk (other products are available! e.g. www.tiranti.co.uk).
Top Tip 5 -
When the pewter has set, the insert can be removed from the mould and cleaned up in the lathe before inserting into the box ends and the threads formed using a matched pair of thread chasers in the normal way.
Top Tip 6 -
Many thanks to Paul for an excellent demonstration which I am sure will have fired up a number of the audience into experimenting with this interesting and attractive addition to the art of woodturning.