vermiculite/portland question

[skemcis]

I got the final keystone in last night, and am wondering if I should be applying the vermiculite/portland mix right away, or wait until the fire clay is cured? Any help here greatly appreciated.

Ian

[Neil2]

Re: vermiculite/portland question

There are two schools of thought about this.

For mine, I applied the vermiculite/portland (over several layers of heavy tinfoil) right away. I kept this damp for about a week as I proceeded with other tasks to finish the dome.

I didn't start firing and curing until the dome was complete.

Part of the reason I did this was that I built it during December/January and wanted some protection from rain before I started the curing process. (I'm on Vancouver Island)

[Rastys]

Re: vermiculite/portland question

Ian,
don't complicate your build any more than necessary.
As I built mine, I had a tarp over the build area as it was winter and raining regularly, and plastered my dome with the vermiculite cement immediately after dropping in the keystone.
Why wait and then re-wet your dome. I was sensible with my drying but nowhere as careful as other have been. Sure, build up your temperatures slowly over a week or so but dry the whole oven once rather than several times/sessions.

Rastys

[skemcis]

Re: vermiculite/portland question

Thanks for the input folks! That's what I thought, but needed some reassurance.
This forum community is amazing. Answers to questions from close to home to halfway around the world. I can't thank you folks enough.

Ian

[Neil2]

Re: vermiculite/portland question

Be patient with the curing process.

Nothing much seems to be happening with the first 4 or 5 firings, then, as it drys out, the retained temperatures start to go up quickly.