Would the clay you are using be unsuitable for these raku glazes?
Havent lookwd at your images If pots.
Could be "Absolutely naked raku " technique:-)))
Couple of areas where clay can be sensitive to fast heating, also slow at start, or even candling if you not sure of moisture content and clay thickness. Some folk hold somewhere around 700-800 °C to drive off xhemically bound water but if you havent had to up until now, I wouldn't start.
Let's know how you go,centainly save on energy and time.
Run it up as you would for your normal bisque i.e.the same ramps until I'd say
600°C then proceed as for your normal glaze firing ramps to goal temp/ cone.
Are those whits spots holes in the drum?
Looks too far gone for me to touch. The metal us really pitted. Have you seen it with the auger turning? Can't see this pugmill lasting or even working for long.
Some if the crazed old pots you see are stained over time whilst the ones stained by the potter are distinct in their depth of colour and size of craze pattern.
Yes a hood with flue will, but hoods generally to suck up fumes on inside firing, not needed outside firing, can't remember the physics behind it. Why chimneys have a specific design.
Seconary and primary air intakes .
Looks like an abused item if only 4yrs old.
The bottom element is stuffed, the other ekement is sagging, bricks/ kiln have been cracked or??
That corroded stain on controller and electric box mesh is a concern, what would the inside of that box look like I wonder. So price 2 elements and pyrometer as minimum outlay of $
Ask for a photo of inside of control box....
Havent really studied closely but these things are glaring and signalling avoid imo