How much Hawthorn fireclay should I order for 42" homebrew

[Mongo]

I went through 1.5 50# bags for a 42" oven. Fire clay from a masonry/brickie supply store is relatively cheap.

Funny what we sometimes put ourselves through. Just got off my but and made the drive to buy another sack of clay for $13.
I pretty much hate the firebrick dust based mortar.

[Padraig]

Thanks for the replies UtahBeehiver and Mongo . I appreciate it.

[UtahBeehiver]

I went through 1.5 50# bags for a 42" oven. Fire clay from a masonry/brickie supply store is relatively cheap.

[Mongo]

I'm building a 42 inch dome with an oversized flu gallery and have just now reached the end of a 50lb bag of clay with my gallery and flu about 85 percent complete. Had it been normal size 50lbs would have been fine. I'm now using brick dust harvested from my tile saw and saved during my build.
Beveled dome bricks and a normal amount of waste.

[Padraig]

I intend to do beveled/angled bricks. Will I need more than 1 50lbs bag of fireclay?

The forno bravo plans say I think "150-200lbs" mortar - I presume they mean dry mix of high heat mortar.

With 3:1:1:1
200lbs dry mix contains 1/6 fireclay as a proportion = 33.33lbs.