Hi Ken !
I wondered which direction you were going and I see you did well !
Opening an air wash to the atmosphere is going to prevent a lot of air from entering through the tubes. The path of least resistance would be directly into the front over glass, so with so many tubes you are going to loose the velocity coming in through the holes.
Also keep in mind the size of the holes determines the velocity of the air entering. If you open them up, thinking you can close the secondary intake, you are slowing the incoming air through larger ports. You want them small to make jets of air with higher velocity, not slow moving air through larger holes. Larger holes could require more chimney, plus your altitude has lower pressure to start with, so if it works with that size hole you better leave well enough alone.
Directing flame from holes pointed downward across the glass keeps the glass hot preventing condensing of vapor and clean. Normally the tubes are lengthwise with the glass and the front tube is close enough to direct heat over the glass. It should stay clean at least from the top down half way or more and only build up an accumulation at the bottom. Your burn tubes are very high and far from the glass where they need to be to direct flame toward it.
You need 6 inch clearance on the bottom unless going on a non-combustible floor or hearth.
What was your altitude again, so other commenters can take that into consideration?
I believe you could only get something like a 5 inch pipe and flue ?
Until tested with the chimney that will be used and cold temps, you're not getting a good indication of what kind of ignition you will have this winter. A sluggish burn or not lighting off much at all now may be great below freezing temps and really rip at 10* f. If you routinely see temps below -10 f, take that into consideration before trying to make it perfect now.
I did a calculation years ago of the hole size compared to square inch opening of intake of manufactured stoves at Lowe's. They all came up with quite a bit more square inch opening of holes compared to the area of intake opening.
Thanks Coaly, you helped with a lot of information, I wish I could have read this post prior to installing this weekend We have no internet at the cabin, so I just got this data Monday AM my time at work.
So I installed it with the help of several young backs and hooked it up to my existing stack, (which I think is undersized but we will test) I am a firm believer in empirical testing on all things so this should be fun. I had earlier tested it in the shop using single walled 4" pipes that I ran up 16 feet.
prior to moving it to the house I drilled 6 1/4" holes in the secondary air tube to redirect air to the glass as an airwash as the tube is directly above the glass. This had the effect of (as Coaly suggested above) of killing velocity on the secondary air.
In the house the flue pipe is a double walled 4" stainless with a total of 20 feet length. Our elevation is 1100 meters (3500 ft) on the northern side of Mt. Fuji
The first load in the house was a batch of Oak, all properly seasoned but small splits, small length 14" (it was originally cut to match the old stove). I filled the stove in a NS orientation and lit it off and it burned from 2000 to 0700. on the slowest setting i could maintain a slow reburn at. Heat output was too high for this time of year and we had to open windows to adjust temp. I ended up closing the primaries almost completely and the air wash fed the fire (whoops!) but the glass was kept clean reburn was weak though, so I will plug two of the air wash holes and I need to close off some of the reburn holes and try again next week.
the stack temp was a little lower than I prefer, (IR gun at the only elbow in the system) only read 260 but when I went outside with a flashlight saturday night to check it the stove was burning really clean could not see any smoke at all so maybe its OK. I will monitor and check as I play and fine tune it. my old stove ran much higher stack temps, 350~450 at the same location, and same IR gun, but it had no reburn nor was it air tight.
so take aways from this experiment are Coaly's baffle ideas two thumbs up. My reburn circuit is too big, and I will end up welding shut about 1/4 of the holes, and I need to weld shut two of the air wash holes. once the above are done next week i can fire it up and test it out again.
the lower stove top plates average temp with reburn was 600 prior to going to bed. The upper plate was cruising along at 500ish when I woke up in the AM we still had fuel and it would have kept generating heat but I closed off all of the air inlets and the damper and killed it. It is hard to maintain reburn on such low settings, and that might be due to me drilling the airwash and losing signal on the reburn, or it might be too many holes in the reburn itself (260 1/8" holes)
for the guys asking about the glass, I ordered robax custom cut from the states, so no worries there. the space to my wall is only 16 inches, but I have a layer of 5/8" fire board that has a 1" air gap between itself and the wall, this is the same as I had last year with no issues. the base where the stove sits is a layer of 2.5 inch firebrick as the actual floor (?) it is the same as the firebrick in the stove itself. below that is a reinforced section of 4x4's to support he extra weight of the stove and whatnot.