refiting 1960 smoke dragon for secondary burn

[eernest4]

First, hi to all my freinds here at hearth.com

I've been away from the board for a week, trying experiments on my wood stove
because it was eating 1/8 cord per day with coals going dead in 3 -4 hrs, & I could see that my firewood wouldn't last out the winter at that rate of consumption.

The first change I made was to remove the 4 inch high grate that I was building my fires on & build a fire on the 1/4 inch plate steel floor of the stove, after I lay down 2 inches of dead ash as a insulator.

Opps, cooking timer just started beeping, gotta go.
To be continued:

 

[eernest4]

kitchen duty done.
back to part two- of "to be continued".
So, without the grate, there was a lot more room for wood in the firebox & I had to fill er up, just to see what it would do.
I got a 3.5 hour burn to a huge pile of red hot embers, from lite up at 6 pm to red hot embers at 9:30pm & then, embers stayed hot until 4am, for an extra 6.5 hours of heat.

So, counting the ember time, I finally got my first 10 hr "so called" burn.

This in turn, started a dangerous situation, namely, me thinking!! :lol:

My stove has a domestic hot water "coil", not a real coil, but seven- 29 inch long, 3/4 inch black pipes joined front and back by double 90 degree elbows. These could no longer be used for domestic hot water because of a high pressure leak only apparent when the stove was burning. At any rate, the pipes went , zig-zag, up the right side wall of the stove & then across the top of the stove to exit at the left rear of the stove(viewed by) facing the front loading door.

Today , I started drilling a series of 1/8 inch holes in the "ex" water pipe to provide preheated secondary air at the top of the combustion chamber, where all the heat and smoke is susposed to be.

The secondary air has to go through around 8 feet of pipe in order to get to the section of
pipe on the top of the stove where I drilled the holes, so I am sure that if the air ever gets there, it will be well preheated.

I am hoping that the stove , being connected to 8 inch black flue pipe to a 40 foot tall interior chimney, should have enough draft to pull secondary air into the pipe and out of the holes at the top of the combustion chamber. I drilled 1/8th inch holes to start with, but they can be enlarged if required.
I had no idea what size holes to drill, so I went with 1/ 8 th inch as that is my fav piolet drill.

I did take the precaution of putting water valves on the ends of the "ex" hot water pipe
where it enters & exits the stove & they can be closed down to regulate secondary air intake
or opened up or even removed completely, should more secondary air be shown to be required.

The final step for this set up is to line the bottom,sides up to 12 inches and back of stove up to 12 inches with fire brick to retain & concentrate the heat.

To be honest, I don't know how it will turn out, but I will either fire it up sometime tonight or tomorrow, depending on when I end up getting finished with modifications.

At any rate , I can always return it to the way it was before by meerly putting end caps on the inlet & outlet of the ex water pipes.

So, that is what has been going on around here with me lately.

If you have any ideas, comments, sugestions or warnings, please chime in here, as I am
looking forward to your thoughts on the subject.

 

[Corie]

1/8" is on the small side of secondary holes. That doesn't mean it won't work, BUT you'll probably want to use something more like 5/32 or 3/16.

But I digress; you should try to get a piece of ceramic baffle board on top of the tubes. That would be a BIG help.

 

[Jimbob]

Sounds like an interesting project. Keep us posted on your progress. Pics are always welcome, too. :coolsmile:

 

[KWillets]

Darn it, if this works I'll have to try my half-baked ideas. We have an old "Universal" wood/coal range in our cabin that I'm thinking of decommissioning, but I'm trying a few things first. Last trip I managed to line the bottom and sides of the firebox with firebrick and got somewhat more complete burn. I'm thinking of fishing a secondary burn tube across the top, with a baffle.

Once all this is done, I'll have a firebox about 1/3 cu. ft. in size.

 

[eernest4]

Dear K willets,

How big is your fire box now?

1/3 cu. ft seems rather small to me.

Cant get much wood in there, what is that, 9 inch x 8 inch x 8 inch?

I started with a 12 cu. ft fire box, so when I loose 2 cu. ft to 3 inch thick fire bricks, it is no big deal.
I still have 10.0 cu. ft. left.

But the ceramic baffle plate seems to be a problem as I only have 3/8 inch clearance between the pre-existing water pipes that I am converting over to secondary air pipes & the top of the stove, for the first 19 inches back from the door, after that , there is 6 inch clearance because of the step in the stove top, back another 17 inches.

Be aware that this is a serious ongoing modification and not a joke post.

Metal is changing shape, a little each day.

And yes, I expect it to work better,to some degree or another, when i am done & I will repost with results, but Im no scientist guy that measures before and after in degrees celcious.

But I can tell you how much better it seems to be opperating.

I do what is logical & easy, considering I already had the water pipes in the stove; the guy sold me the stove because the pipes leaked , but didnt let on about it.

I thought they were good water pipes & was going to hook them into my hot water radiators, but that never worked out for many reasons, but mostly because my friends wouldn't help
(they shied away big time, can of worms,bite off more that we can chew,& more other warnings)
with the job & it was too much to attempt singlehanded.



now maybe i find a better use for the existing pipes as preheated secondary air pipes.

I figure it better to try and fail, if i must fail, than not to try at all.

And if it dont work out well, I can easily return the stove to how it was before I started in on it.

And so far, I am doing this singlehanded, but with the great help of all the advise anyone is willing to give me about it.

 

[KWillets]

Your idea sounds a lot better than mine, and I'm encouraged by your efforts. In my case everybody wants to keep the stove, so I can't replace it with a modern model. So I'm trying what I can before I have to convince everyone that it won't work. It is a fairly small firebox, made for short cooking sessions, so there's an element of futility in my endeavors.

 

[KWillets]

Thinking about this, will the higher combustion temps affect this type of pipe? I'm aware of the stainless steel tubes that are often used, but will, eg, regular black or galvanized work? Will it corrode or rust out?

 

[eernest4]

Dear Kwillets,

Yes and yes!! OH yea! & yes!!

Regular black pipe will work qiute well for a number of years and will eventually rust out. I'm using it & I'm not worried about it in the least. When it goes, so does the stove,
because by that time, the stove will have paid for itself 4 or 5 times over.

I'm betting I get at least 4 or 5 years out of it.

Galvanized is a bad idea, it will immediatelt begin to corrode & after it has corroded ,it will start to rust & eventually,it will rust through, probably faster than the black pipe does.

Even the strainless steel burns out and rusts & has to be replaced , but manages to last the longest of all.

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

(The resident comedy hour)

Its all just a matter of time, you see, pipes,people,cars, cash,it all wears out or gets used up eventually.

Help, I'm wearing out and my cash is getting used up :lol:

My wood stack is dissappearing!!




POST UPDATE
*****************************************
Had to do the weekly shopping today ,so i didnt get to finish my stove retrofit & i was too beat from shopping when i got back, to start working, so i just take it easy. My pel pro 50,000
btu pellet stove is getting qiute a work out, burned thru nearly 3 bags of pellets in the past 4 days, as it is the only source of heat, besides the money burner emergeny oil back up, while the wood stove is being modified.

Its manfully trying to heat 5 rooms & keep another 900 sq ft warmed a bit & not doing a bad job of it, just 40,000 btu undersized for what I am asking of it to do, so ,I keep some doors shut to cut down on its work load. Some vacant rooms icy ,other occupied rooms toasty.

Last winter,i had days where 5 above & windy outside & I had to run both wood & pellet together, at the same time, to heat the house nicely.


HANG IN THERE, BECAUSE EVENTUALLY EVERY ONE BUT us here, will GO BROKE, PAYING OFF THE OIL MAN, AND WE WILL STILL HAVE, at least some,MONEY LEFT.
And then, we can laugh , all the way to the bank
And, those of us that are really smart, & young enough, will start selling rounds to the rest of us.

 

[North of 60]

YOUR HOUSE INSURANCE BROKER WILL BE STOPPING BY SOMETIME TOMORROW.

 

[eernest4]

north of 60 ,
hi! from north of 59


Good, I'm glad he is comming!
I'm going to cancel the insurance and ask for a refund on my premium, no sense in waiting until the next premium aniversary to cancel.
Big waste of money anyways. I should have done that years ago. Money for nothing, year after year after year, How smart is that??
House is 97 years & never had even 1 fire. Well, I dont know for sure that there were no fires before 1948 , but I do known for sure there were none after 1948.

 

[eernest4]

hey kwillets,

How are you comming along with converting your kitchen baking stove to secondary burn.???

Wont the secondary burn ruin the stove for cooking & baking, or do you intend to use it only for heat.

i took a look today at the old 1930 kitchen baking oven stove that I have in storage in my garage and its firebox is way small, only room in it for three - 2 inx3inx12in
in it, or maybe you could get your hand in sideways if you rolled up your sleves for clearance.

But to get a work light or power tools in there, absolutely impossible.

Maybe you have a model with a bigger firebox.

The stove I am working on, I lay down inside it on my back & let my feet hang out the door. Its 3 feet long & two ft high & 2 ft wide inside the firebox, so i can get in there with a work light,and still room for 3 power tools.

i can't immagine how you are going to have room to work with that tiny firebox unelse you completely tear apart the stove.

Is it cast iron with take apart sections & if it is , can you still get new gaskets when you go to reassemble it???

if you can't get new gaskets or make your own,dont take the stove apart as you will end up ruining it without new gaskets.

And how many frozen bolts will break off when you go to take it apart.

So far, I have had to drill out oversize & retap to the next bolt size, 4 times already
but I am pretty sure I am done with all of that now, as I am on the reassembly phase.

I have preheated primary air completed, secondary burn air almost compteted & next comes relining with fire brick.

 

[KWillets]

So far it's still in the planning stage . It will have to wait until our next trip up there, since it's a vacation cabin. It's a smallish firebox, and I don't think I could improve things significantly. We don't cook on it much, partly because it's never seemed hot enough with just wood. When I put the firebrick in it got quite a bit hotter on the cooktop, and we did some cooking on it. The firebox is about 9" wide and 12" high, and fairly deep, but I think it needs lining which reduces the volume. Right now it has 1 1/4" firebrick across the bottom and sides, just loosely laid in. It seems to help it burn well, and the embers burn all the way down instead of going out. If I get more time I can cope the firebrick to fit across the bottom better, and possibly block the draft which blows in from the ash catcher below.

After all of this armchair stove building, I think I'm ready for the next step -- a bigger armchair.

 

[eernest4]

You may be arm chair stove building, but I have my sleves rolled up & and my tools out of the tool box.

I' m not sure how much time i will have to work on it today because i have to get my snowplow ready, blow up the flat tire ,charge the battery & dump 5 gal of gas in the tank.

As well as the snowblower. We have a winter storn advisery in effect from thur morning until late thur night calling for 6 inch of wintery mix sleet,snow,ice, freezing rain & more snow.

So I'd better go fill up the gas can, blow up the tire, yet again, & put on the battery charger; because tomorrow it looks like I will have to play snow plow/blower man.

You know,winter really sucks when your 60 years old. I remember praying for snow when i was 20 - 40 so i could go skiing at killington on the tripple black diamond mogils.

All that ended in 1994 when I got lymes desease which ruined my joints for me.

It hurt me to snow & water ski after that. I tried to , but no go,too painfull.

The golden years are 18 to 40 , and dont let anyone tell you different. After 40,its all down hill.


With your stove, if i were you,i'd just put some nice fire brick lining in it & let it go at that.

After all, your not trying to heat 2700 sq ft like i do.

 

[eernest4]

Well, I am happy to say that I have finished the refit today and fired up the stove.

I thought I'd give myself a Christmas present. Its nice to have the wood stove back on line as i was getting sick of burning my pellet stove.

Not really sure exactly what I have yet, all i know is that the stove acts totally different from the way it used to, so I guess I could say I have meet with at least partial sucess.

I fired up at 6:30 am this christmas morning & we will see how long my wood load ends up lasting.

As far as secondary burn goes, all i know is that air is getting sucked into the inlet of the secondary air pipes, weather it is enough air or not, I don't know because I have a solid metal door & can't see the flame.

As I mentioned, the stove is burning totally different, so i will have to learn it all over again, & that will take some time. It does seem to be working ok to me ,it gets hot enough & pumps out the btu's , so the length of burn & the amount of wood consumed will be what i will be trying to determine over the next week.

I am also learning to lit top down fires ,for the first time, sowith all these changes, Its no big wonder that I don't know for sure exactly where I am at with all of it, yet.

I suspect that I may need to enlarge the secondary air nozzle holes into the firebox, but, I'm not even sure of that yet.

Hopefully,Time will tell.
Basically, I'm not about to brag until I know, for sure, that I really have something worth bragging about.

i will update in about a week, as I have to try many different settings & fire configurations to find out what works the best & what don't work.

 

[Todd]

What are your stove top temps now compared to before your modifications? With secondary combustion going on, you should see a rise in the stove temp and decrease in the pipe temps. Did you install a baffle?

 

[eernest4]

Unfortunatly,
i was unable to install a baffle because the stove had a domestic hot water coil
strung down from the top about 3/ 8 of a inch under the stove top.
Because the hot water coil leaked when I bought the stove used, & could not be used for hot water, I decided to try converting the hot water coil into secondary preheated air supply, by drilling air jet holes into it at various locations.

I'm not sure what stove top temps were before i did the conversion because I only have one stove pipe mounted magnetic vent pipe therometer & as I said so;id steel door makes seeing flames impossible.

But thank you very much for the info, i will remember it ,as It will more than likely come in usefull sooner or later.

After my first test firing, I am highly pleased to say , I have achieved a 8 hour burn,
from 6:30 am today to 2:30pm & when I when down to refuel I still had a nice hot active bed of coals & a stack temp of 250deg & the stove was still putting out hot air from its two 3 in dia pipes which constitute its primative 1960's style heat exchanger.

i put large splits down on the embers & they ignited in about 90 seconds.

No more 4 & 5 am stove feedings & hello to a good nites sleep, finally!

The overnight burn alone makes the whole thing a big sucess in my book & if I can get secondary burn to function as well ,that will be just an added bonus for me at this point.

But it would be nice if i can get that beast to cut its wood consumption in half.
Because i would only have to scrounge & cut & split 1/2 the wood each yr.

I may still buy a englander 50-30ncp if i cant get my beast to curb its appitite of 3/4 cord a week.
If oil/money burner fuel prices continue to soar, free wood scrounging may become a thing
of the past & should I have to end up paying $160.oo a cord for unsplit rounds, the smoke dragon will soon find its butt on ebay with the 50-30ncp in its place.

it seems likely things will be headed this way, later if not sooner. So i will be keeping my eyes open for end of season clearance sales , if for no other reason than to cut my wood consumption by 66 %.

we will see, as I am not done with my tests & may yet do further modifications,if cost+pita modification factor vs.benifit looks favorable.

At this point, pita mod. factor is the major parameter.

 

[Todd]

Did you ever consider turning that beast into a catalytic stove? Maybe you could take those water pipes out, install your baffle with cat in front of it, then make some kind of bypass in the rear. With a cat and that huge firebox you would probably get a 48hr burn out of her. I just don't see secondary air tubes working up to par without a baffle.

 

[eernest4]

Test run #3.

REFIT SEEMS SUCESSFULL,except for some smoke still comming from chimney, but at a acceptable level.

Something has sure changed with my stove, thats for sure. First night since oct 1st didn't need to use an electric space heater in my bedroom & outside temp is 22*F, bedroom @ 72*.

I sacked out at midnite
but a light chill woke me at 4 am , so I figured the stove must be out, 67 * in my bedroom, but kitchen was 72*. Had to be that the stove was out, I had last refueled
it at 2 pm, 12 /25/07.

So I go down the basement & its still 85* down there, the heat exchanger is still pushing out warm air & the stack temp is still 120*f

I still had live embers in the stove after 14 hours, enought to lite the new fire without matches or newspapers!

That translates into the wood that i used to burn up in 4 hrs & have a dead stove now
can last up to 14 hr & still have some warmth.
Based on that alone, i have cut my wood consumption by at least 50% to maybe 60%, so It was all worth it!.

Now ,I have enough wood to get through the winter with. Before, I was thinking I'd probably run out sometime in feb 08 or mar at the latest.

I seem to be getting some signs of increased stove top temps with decreased stack temps, so some kind of primative secondary burn is occuring.

I regret having a solid steel door because I can't see anything of how the wood is burning.

But, I can see air being pulled into the secondary air piping inlet when I put a cigarette near it, the smoke goes in the pipe, so something is happening but, it is not the same as the flame
show I see thru the viewing window in the pretty pictures on the stove mfg websites.

I am still getting some smoke comming out my chimney, not bad acceptable levels of white smoke but consider that I am now running the stove with the primary air only cracked 1/8 th inch open & the flue damper at 45 degrees or 1/2 to 2/3 closed.

Before I used to run with 3/4 to 1 in open on primary air & wide open flue to stop smoke. It used to stop the smoke but ate up the wood in a 3 hr. burn to the tune of 3/4 - 7/8 th of a cord a week.

Now I can probably get by with under 1/2 a cord a week or less to heat 2700 sq ft on 24/7 burn.

Tomorrow, I am buying another magnetic thermometer to monnitor stove top temps with so I can compair stove top temps to flue pipe temps.

Other changes. I have to close the cellar door because the kitchen gets too hot & I find myself opening doors to cold rooms to cool down the kitchen & living room.

so, more testing forthcomming, but except for the smoke which i was hoping to get rid of, I am very happy with the results.

At the very least, I now have enough wood for the winter with maybe some left over for next winter, due to a reduction in rate of wood consumption.

So I nailed three out of four of my goals.

75 % sucessfull ain't so bad, I could live with that!


1. longer burn time, yes
2. reduced wood consumption, yes
3. more heat, yes
4. less smoke, ??? some reduction, maybe , but I can still see it comming out the chimney so
I'd have to say No.

I know I didn't do everything that could have been done to that stove in a full tilt, no holds barred refit , but I was working singlehanded, that is, by myself with no help, & so I had the
pita factor(pain in the --- factor) to take into account & so i did all the easy fixes & ignored the
one really hard , nearly impossible, one as being too much work.

So, not too shabby! Even if i do say so myself.