Rumford-izing a fireplace

Hello Permie Pyromaniacs!

After some measured success in building a RMH (much thanks to this forum) , I am taking on an old boxy fireplace. It never drew very well, despite having a good flue and smoke chamber, so I am thinking converting it to the Rumford dimensions (following the specs from Rumford.com). But, in typical fasion, I have no idea what I am doing! I know that Erica and Ernie mentioned that it can be done. But, I don't want to do a huge messy rebuid. My idea is to mortar up fire brick using fireclay/sharp sand and hand plastering a "throat" using metal lath and natural plaster.

But has anyone done it?

Any ideas what I should use for plaster for the "throat shape"?

Thanks for any help.

Lorne

Lorne Babb : Membership has its privileges ! You're in luck, Simply Google-ing Videos of Building Rumsford Fireplaces will connect you to a mother load !

It also gets my quick rundown on selecting U-Tube videos. U-Tube Videos should be rated like a poker hand. A full house is a good hand -3 of a kind and a pair kicker !

The three of a kind is The videos with a 1)build, 2)use, and a 3)follow up video sequence -all about the project you are interested in .

Are things clear does the poster keep up on his comments answer questions and have useful communication with visitors ?

Generally a single "Look what I did'' with no follow up is a kiss-of-death!

And a couple or more videos on another subject shows the poster is proud of the work he does and is pretty handy

In all cases ''Cavat Emptore" For the good of the Crafts ! Big AL