Bell Roof repair

Hi All ;  
After almost a foot of snow & single digit temperatures  last week ... this week it is practically summer!
Sunny with highs in the low 60's and lows in the 40's !  In November!!!
I've been collecting pieces and planning to replace the roof on my shop stove
With temps like these its time to do this.
Without constant full support the hardy board want's to crack... with a warm stove you don't notice... with a cold stove it leaked like a sieve!
Good thing there are 10' shop doors to air the place out.
I'll be adding angle iron supports every 8" . A new sheet of 1/2" hardy board will go on that.
And then the whole thing will get a cob layer and an all brick topping.

While I'm going that far, I may as well make some high performance improvements.
I have exposed my fire box. I'm building a new wider support from the floor up.  
This will allow me to use  Skamal insulated fire bricks  around the core and then red clay to surround the Skamal's.
By better insulating my core, more heat will go into my bell.
The 6 minute riser is still perfect.  I'll use a new piece of 1" cf board for the firebox roof.

By next weekend they are predicting below freezing temps during the day and teens at night.
I'll be glad to have this done before then!

Chuck a metal plate on top of the firebox!



You won't regret it!

Today I got all the angle iron cut and installed .
Almost finished the lower brick surround.
Next will be the skamal insulated firebricks and then a clay brick covering.
Install the barrels and then the roof can be fit into place.
After that let it get cold again!

Wow,  very cool!
I'm surprised hardy board works at all,  to be honest.
I have always heard that Portland based products couldn't survive at the top of the bell.

Hi William;
Thank You!
The only reason I can get away with it (sort of) is because I am using double barrel's over the riser.
The metal barrels shed so much heat that when it comes down into the bell it is significantly cooler.
I'm hoping, that with complete support and a cob and brick roof over top that it ill last several seasons or more... (I hope)

Thomas, reading this, it hit my little brain.

Are you sure about the angle iron? I would be afraid that it might warp. I always say T bar for ceiling support.

Have you made expansion pocket at the ends, so these don't push your walls?


HTH.

Hi Max;
Its 3/16 th so its pretty thick angle.
I did allow them room to expand, so no problems there.

I expect that even supported this cement board has a limited life, so I'll be seeing these angles again in a few years.
I can always double them up then if they are warping.

Ok Thomas.  It's just that it hit my little brain.

You know the two "legs" of the angle being heated differently, one being in contact with the cement board, a sort of heatsink;  and the other one fully in the hot gases. I thought that it could cause twisting.

Hi All;
As usual things are taking longer than I would like.
Its sat night and I'm still not up and running... but its getting close.
My high performance insulating upgrade to the firebox is 98% done.
I need to seat the lower barrel so I can cut the new roof to size.
Then I can put the second barrel in place.
At that point I should be able to light it off.
Let it burn while finishing putting the brick over the roof and the firebox.

Hi All;
It took until just before dark, but the shop dragon is burning!
I ran out of clay so the roof bricks are just sitting there for now.
Lots to clean up & put away but its burning!

Few more pictures, showing how easy ceramic blanket seals between metal and masonry.

After 2 hrs this morning it quit smoking inside and started drafting.  2 hrs later it was over 140 F and rising.
She is throwing quite the steam contrail but there are quite a few water soaked bricks that need to dry out.
New roof is nice & flat with no leaks!

She is drafting like crazy now. Fire is roaring... Shop is warming for the first time in a week!  Good thing as it was 15 F this morning!