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3. Building the Dome
3Q: COURSE 10
Lay Dome Course 10.
This course is made up of Type 3 Bricks only.
Cleaning Tip - see update #2 on Page 7.
3R: THE KEYSTONE
You now have two options – you can cut fire brick keystones using the remaining bricks in your kit, or you
can simply fill the keystone with Refractory Castable
(not Refractory Mortar)
. You have the fiberglass dome
mounted in the oven, so the form will leave a perfect dome shape on the inside of this castable keystone.
We prefer to use the Refractory Castable; it sets just as hard and strong as the fire brick, and it makes the
perfect keystone
because it has complete surface contact with the surrounding ring of bricks.
To make sure the fiberglass dome comes off cleanly, wipe the dome surface with a small amount of vegetable
oil. Add a tiny amount of hydrated lime to the castable if the temp is below 20°C (using the ratio of 1 tsp/25kg
bag). Mix the castable to a thick consistency and pour into the void, vibrating the mix with your trowel to
remove bubbles.
To prevent drying shrinkage cracking in the keystone, cover the wet castable immediately after the pour with
cling wrap. Allow the keystone to set for approximately 12 hours, after which you can remove the fiberglass
dome (it should peel off quite easily, and can then be pulled through the doorway). Check that the castable has
set properly by tapping it with your trowel before you release the fibreglass dome formwork.
Summary of Contents for D95
Page 1: ...D95 Brick Oven D95 PRECUT BRICK OVEN KIT Instruction Booklet ...
Page 44: ...44 Examples ...
Page 45: ...45 Examples ...
