Top plates are made from thick 3/16” steel plate which provides an evenly heated cooking surface on top. On each stove they overhang about an inch and the corners get rounded over.
Stoves with dampers installed have a 5” flue collar to allow for full movement of the damper plate when stovepipe is slid inside.
The air wash intake works by allowing air in over the glass which draws flames towards it to keep it hot and prevent creosote build up.
Ideal air wash position tends to depend on a few factors including stovepipe size and how much draft your stove has. Its recommended to find the proper position by starting with it wide open, and gradually closing its position to where your glass still stays clean while a minimal amount of air enters the stove. This may take a few burns in the stove to find the best position.
Primary air intake on stoves allow for a wide range of settings. They function using a sliding plate with a pin welded underneath to prevent the plate from sliding out. To let air in the plate gets slid back and to close air off the plate gets pushed in.
The more air let into the stove, the fire will burn hotter and burn your wood/briquettes faster. A stovepipe thermometer placed 18” above the stove top plate on the stovepipe will tell you proper stovepipe temperature which is maintained by the primary air intake plate.