Vermiculite Cement Dome - Brittle

[Naivaklam]

Hi this is my first post, I wanted to say thanks to this community, all of your messages guided me to build my first wood fired pizza oven.

Now I need your help, I built a dome with Vermiculite and Cement on a 10:1 ratio.

I let the oven for 2 weeks in the sun before I started the curing process.

I started my first 3 small fires and then added the insulation on top with chicken wire and stuccoed it.

Until now I don't see any cracks, but the only thing that worries me is that the dome still feels that it's not "set".
Some parts of the dome are strong and solid others are still brittle and crumbly.

I did today my 4th fire and I am hoping the more fires I do the stronger it gets.

Is this crumbliness still normal in this stage?

Thank you all

[UtahBeehiver]

Unfortunately, the use of a vcrete, as the primary dome material, is not a recommended practice. At a 10-1 ratio, it will not have much structural or abrasive strength. We see the promoting of this type of vcrete use on YouTube quite often (not in the builders best interest). There have been a handful of one-off builders who have posted on the forum but we never hear back from them on the status of their ovens, There is really not much that can be offered to help you solve this issue.

[Oogie]

Thanks Russell! So glad I found this forum, as I wad wondering about the long term outcomes of folks on YouTube that espouse various vcrete approaches, stability ball mouldings, etc.
Oogie