separating arch from inner dome and floor

[GRAHAM HALL]

Re: separating arch from inner dome and floor

So what was your vericulite concrete mix made up of?have you photos of this gap.
I`m about to install my arch and oven and find this usefull as my materials are obviously going to expand and contract at different rates and was wondering if my arch would crack?

[david s]

Re: separating arch from inner dome and floor

I used a 5:1 vermiculite,cement mix and made the gap that it sits in about 10mm