Raising cement block walls. Dry-fit blocks, without mortar in between (similarly as with building dams for instance – it’s strong), then these cinder blocks are filled with concrete. But of course these blocks can also be mortared first, it is just up to a personal preference for how to go about that. Masterly Tail oven design (3G MTo) – 3G MTo Main Page

1. Even though this is great slick ash drop design, the ash slot isn’t necessary for the oven to perform well. It can be simply completely left out from the construction as ash can be cleaned out by removing it on a paddle, very easily. The function of this ash shoot is only to drop the ash and embers comfortably down when it is being raked out. Ash volume from 200+ firings can be accumulated in the ash storage area. While we are at it; heat up 4 or 5 times before cleaning the oven. (please don’t throw the ash to waste, instead spread it in a garden!)
2. Post here (below) exact dimensions of your common cement blocks. Full size, half size and quarter size blocks – the large size that I used and 1/3 thin. In inches or millimeters units. This is to workout exact slab dimension for the ground slab for oven builders in USA, Europe, Australia, Canada, New Zealand, Asia, Africa, South America, you name it where else.
3. Otherwise, the slab extends on each side 1″ – 25mm from the walls.

2. Raising block walls (and the slickest ash-drop design!)

Image #0185 - cutting down one small left over wire mesh piece. These off-cuts will be used to strengthen concrete poured into the slim blocks.

Image #0209 - Because the gap in them is narrower, to strengthen the concrete joints, inside these thin blocks you can see metal pieces from cut down wire mesh. Image #0185 above shows the mesh being cut.

Image #0240 - for filling of all the slim blocks with concrete – because the opening in them is narrower; when I only have a concrete blend with large stones in it (sand with stones mix) to make my days easier first I sieve the larger stones out. Because only a small volume of concrete will be necessary for filling of these thin blocks, one bucket prepared ahead will last a long way – a photo describing the sieving is in the finishing-walls section.

Part 2 “how to raise cement block walls” contains 90/181 photos.
Total images 0141 – 0321 (out of 2,785 all up)

3G MTo main page.

There are also the Swishy oven and Original MTo designs to consider and to look at.