Hope you excuse me for asking so many questions, but am very curious about me.
When I tried to find the fault last time, I saw a build-up of something around the nozzles, I have not seen it on the old unit, what is it and should it be so?
Shouldn’t it make the volume in the fire pipe to be smaller, so if I screw in the nozzles I will use more coal for gas production?
Looks like baked tar to me… l culd be wrong! Anyway, if it is baked tar thats probably a good thing. Means the firetube is cool enaugh to condense tar. It just needs time for enaugh tar and ash to acumulate behind the nozzles to a point where its hot enaugh so no more can escame behind nozzles. When acumulated tar bakes it foams up and makes a exelent heat insulator!
No, the space behind the nozzles is supposed to fill with charcoal fines and ash. Seal it so that tar cant escape behind and mostly insulate and contain the heat in the center. Screwing nozzles in will make the gasifier biger but you will start loseing heat outwards.
Here is a picture of the grate and bottom of my firetube. There is about 1 1/4" to 3/4" of spacing between, because the grate has warped a little. It is made of stainless steel and it has Lots of holes punch in the plate. They are a 5 pointed star shape. I can stick my small finger into the star. It slips a little charcoal into the ash dumps. I like that, it keeps it from plugging up in the grate. And the charcoal will still slip out to the sides of the grate if I forget to clean out my ashes and it gets to full of charcoal and ash. Yes, I have done that a few times. Plugging things up and having to clean it out is no fun.
Bob
Yes Jan, that can be like not dumping out that ash area but it is on top of your grate. The grate works best when the small pieces of charcoal can pass through the grate with the ash. My charcoal is about popcorn size and smaller that makes it through the grate or go out the side between the grate and firetube. I can screen all the ash out and small pieces. The larger charcoal can go back into my gasifer to be used again. By doing this I just made some rocket fuel from my gasifer by cleaning the ammo box ash dumps out and cleaned under my grate area. I am careful not clean on top of the grate just leave it alone. This is important, I do not want to disturb or move the charcoal bed above the grate.
Bob
Thanks Robert for the picture, nicely done.
So the hole is about 5 / 8- 3/4 "approximately?
I put the angle irons apart yesterday, to see what it looks like today.
The star shape was to try and keep rounded char bits from plugging a hole by gas passing through the points. No idea if it worked. Next one I make will be slots.
Did you mention somewhere that grate warped on you? EDIT: Oh, I see you posted that a few posts back on this thread.
Yes Chris it did have a little wrap in the grate. If it would of had cross bracing weld in it might not of had any warping. I recall just hammering it flat again. It did warp again but does not have any effect on the gasifer. The edge is lower then the center, this works good for slipping a little charcoal no ash building on this grate. The star shape works good. I think slots or × shapes would work good and a lot easier to make.
Bob
I have tested vacuum gauge a bit, and get these values, I think.
Can they sue? I think it’s pretty tight in the grate, (the gasifier) do not know if I have to open up a little more in the grate.
I have a sensor between motor and filter, a sensor after the filter and a sensor in the hopper lid.
At between 50-55 mph I get about 3 “in the jumper, 15” after the filter and 20 " between engine and filter.
If I did not count completely wrong.
