Incomplete burning

Hi Everyone,

I just finished my rocket stove and it's not completely burning the fuel.

System is 5.5 inch diameter square made with clay chimney with a layer of cast-o-light inside. (the inside dimension is 5.5)
burn chamber is 16 inch (to the back, not the center point)
Heat raiser is 24 (to the bottom, not the center point)
3 inches space at the top.
The barrel has another barrel on top of it with stone dust in it containing a cooper pipe ( like a boiler or with stone) On top of that is insulated sand.
The whole thing is bricked in, with a 6 inch stove pipe chimney.
I have gray smoke coming out of my chimney which is clearly an incomplete burn.

What did i do wrong?

Without a picture or diagram it is difficult to say but all new fires will contain high levels of moisture and no fire will perform until it  is completely dry!
I have no idea what cast o light is but stone dust and sand will both be an insulators.

Sorry. Cast-o-lite is a refractory. I took an old clay chimney and insulted the inside of it. I knew the riser was a bit short but I tried it anyways. It's burning correctly sideways and fairly rocket-y but it's not completely burning. Short of undoing soooo much work. Is there any danger in running a rocket stove that doesn't completely burn the fuel. The exhaust looks similar to my regular wood stove.
Not to be over dramatic but I am filling a large enclosed brick structure with barrel of wood gas. Someone asked about these things exploding and then answer you guys gave was "no way, all the wood gas gets burned up" Well, what if it doesn't because you built a small raiser for reasons you can't remember and bricked it in and can't change it now.

It is still not completely clear to me how you have built your stove but you say you used a clay chimney and lined it with refractory called Cast o Lite. I would be interested to know how you did that and I am guessing that cast o lite is an insulating refractory?
What did you use to make the fire box and tunnel and how is that insulated?
What about the area where the flow goes up the chimney, how high up from the bottom is the chimney flue?

So some possible issues…. No, or not enough insulation around the fire box, tunnel and heat riser…..
To short a riser and or, to short a chimney, materials are still damp, bad transition  from barrel to chimney pipe.

I made a square mold. (should have used a cylinder) put in down into the clay chimney and then poured and packed tight the insulting refractory cement. burn tunnel was made the same way with added fire brick. I don't know how hot it gets but it's pretty hot. wood ignites as i move it close to the bottom of the feed.
I can't remember why I made the riser so short, the project has taken a long time to build and now i'm depressed and going to undo it. remove the barrel which i don't need anyhow. lengthen the riser and add a secondary air injection. Because at this point, why not? It looks like it won't be done for this winter either.