Stack size for block arch

[Aaron S]

Hi
Building a 3 by 5 block arch. I realize that the stack should be twice as tall than the length. So at least 10' tall. But should it be 6,7,or 8". My thought would be 8" but some times more is better moto I have isn't always right. Just ask my wife )
Any suggestions ?

[madmapler]

I would think 8" would be better as well. You can always dampen it. The one I had was about the same size and I had 2-6" stacks that got red hot pretty easily.

[maple flats]

With a block arch you are generally going to use the whole arch as a firebox. A factory made arch with a 3x5 firebox will have 14-18" stack. I think 8" might be too small. I'd try to go 12" or even 14".