Clay Render Thickness

Hi all
I'm just designing a straw bale home with clay render and would like to know what the current thoughts are on the finished thickness the render? I'm thinking of applying it with a Render Sprayer www.rendersprayer.com.au/

we are currently building an infill Strawbale residence with clay plaster to both interior and exterior. Client wanted the plaster quick thick ( 90mm). after applying the first slip coat - by hand, we then tried to achieve most of the thickness with the next coat -
Naa at 70mm the stuff just slumped off the wall after a couple hours. -
So we then resolved doing more thinner coats - all up about 4 coats , with the final coat quite thin, so we can float then scorch the surface nicely - our walls are now pretty flat.

what actually take most of the time and determines the speed , is the sieving and mixing of the earth to create the desired plaster. - you don't really want any rocks stone or clumps of clay in the mix.