I have just bought a new Wren single wall pipe and the latest diagram has dimensions for an outer pipe. The diagram suggests to make this out of lithoplate and I was told that it could be simply bolted together to make a pipe.

Has anyone made an outer pipe with a Wren inner? How did you do it?

If I use lithoplate what thickness do I need and where do I get it in the UK? Would I be better off getting an outer pipe made professionally?