For the lining I used
1" ceramic fire wool. It cuts with a bread knife and bends and
conforms easily. I wear nitrite gloves and a mask to avoid
breathing any fibers.
I fit it and mark where the hole is with a Sharpie.
Stab a hole through
where you marked.
Bend two thin 1" wide
steel strips. I cut these from an old steel washing
machine back to make two stands bent so the tin rests on them.
I may bolt these in place when tested.
Fire bricks form a
surrounding wall and I added a thin ceramic shelf
to put the steel on, just so I can get it out easily.
I will also be washing
the blanket with kiln wash mix to prevent
fibers escaping in use. Thanks to Neil Blythin for pointing this