Rsf Opel 2 secondary air modification

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Crocks

Burning Hunk
Nov 5, 2018
114
Camptonville CA
I finally broke down and purchased required the stainless steel I had been putting off to do this project. I figured I would start a new thread because my old thread was gettinglong https://www.hearth.com/talk/threads/my-experiences-with-the-rsf-opel-2-kind-of-long.46754/

Always looking to improve a design so here's my go at it. The burner I constructed out of 1.25 and 9/16 tubing(please view attached photos) I also added a ceramic baffle plate pressed up against the factory roof/baffle for main fire box. ( The angle iron stands are temporary) . I drilled 4x 9/16 holes in the 1.25 pipe. I also dirllled the burners with a 5/32 bit with 5/8 spacing between each hole . About a total of 15 holes in each segment. The two outer pipes only have holes pointing in . And the two center tubes I dirllled two rows of holes 180 off on each pipe. View drawing for pressure points/ flow arrows). I inserted 4x 10" 9/16 outer diameter burner tubes into holes . Capped the ends of the burner tubes and Welded it all together .

Anyways so second fire so far with the modification . Video is 45 minutes after full damper (crack more then I typically closed it down before) and the top is hovering about 550. Moderate size loaf of Black oak/ madrone mix.
What do you guys think of the modification? What about the burn rate in general? It puts out alot more heat as of now. Wood consumption to be determined . True test will be when it actually cold. Tonight it's 42 degrees and my house is way hot already .

Enjoy the video please please leave comments here or there . Hope you guys like it
 

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It's definitely achieving some secondary burn. I am wondering why the burn is all on the right side. Is there air coming in on that side?
 
It's definitely achieving some secondary burn. I am wondering why the burn is all on the right side. Is there air coming in on that side?

No the box is sealed as far as I know. But my primary comes down the front glass,and when I have the stove modified to damper down this low the primary flame will favor one side or the other but switches through the burn . Sometimes it even starts on the left side instead . I feel it's so little flow through a big intake it doesn't come out even
 
Maybe it could use an airwash deflector ahead of the tube assembly?
 
Hmm not picturing it exactly. But right now it simply has a screen to help even the flow. Which is bent with some cracking. ( One is on order. But back ordered atm
 
That looks great. I've debated adding additional burn tubes to mine just to help extend catalyst life and possibly extend burn times. I like way it turned out.
 
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That looks great. I've debated adding additional burn tubes to mine just to help extend catalyst life and possibly extend burn times. I like way it turned out.

Hey thanks !!! I'm thinking about adding a catalyst. I cannot seem to find the kit catalyst for my stove so me and a fellow hearth member are debating a way to build our own adapter plate / bypass assembly for the a combustor.

I had loaded the stove at about 630 pm lasts night. Let it burn full throttle for 30 mins then closed her down . At 6 am this morning I had a small amount of coals left ( enoght to put some kindling in for refire) but the box was still a little warmer than ushual. (Maybe just from it running hotter than usual) . I feel it increased my burntime a little. Still a work in progress looking to gain even more efficiency!!!!!
 
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My stove is a whole different stove now. Burns way hotter and slower . Because of how much hotter it burns I was able to put. A very small shim in my primary air. Probably about .015

I do have to spend a little more time making sure the fire is well established before I can damper down and let the secondarys take over

I loaded 4 small peices at 10.30 last night. Shut it down at 10 45. I have this much coals this morning @7 am . Fireplace still tossing off tons of heat , And my house is 75 (too hot for me ) it's been cold and rainy outside it's currently 38 degrees

Another photo yesterday I was just messing around and I pulled the shim completely. All my primary flamed died and secondarys took over . I let it burn for about 30 mins like this. Heat output was ok but a little low and my glass started to brown on one side. This is when I went and ground my air shim paper thin ...... Make a long story short I'm stoked !!!!!!

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Could you explain a little more to help me understand. ? Thanks
An airwash deflector will force the cooler room air to flow down like a curtain over the glass in the firebox. It's a guess that this might even our the airflow. But first check and see if there isn't one already there.
 
Thanks begreen, it does have an airwash deflector installed above the glass.
The lopsided burn could be because the secondary pipe holes are pointed to the right? Can they be turned to point straight down?
 
The lopsided burn could be because the secondary pipe holes are pointed to the right? Can they be turned to point straight down?
I doesn't always burnt that way . There is no rhyme or reason to which way it burns.

It started being like this last season when I modified the primary air to close down alot further than factory. Before it would burn even . But to o fast imo
 
Yes, it looks like secondary air is blowing the fire toward the right.
 
Yeh it will help push it . Either direction . But even with the stock secondary air pipe that points only up. Not into into the main box at all,,, the fire still burnt one side to the other
 
Early in the reload? Looks like its burning rather vigorously for being set for a overnight burn? Or have you not shut down the primary air to the low burn point yet? Secondary's look like they are firing well.
 
Early in the reload? Looks like its burning rather vigorously for being set for a overnight burn? Or have you not shut down the primary air to the low burn point yet? Secondary's look like they are firing well.

Yes early I'm the reload. But you have a good eye sir. I went out 20 mins later to check o. It and it was still burning pretty vigorously. I got the stove so hot that the face warped again compromising my seal. I have had this issue before. I have some 11/16 flat window gasket with tape adhesive. I think today I will add it to the face where it bows in a little and go from there .
 
10 hrs later stove is still putting out lots of heat with plenty of coals to just toss some smaller peices on and crack the door for a minute
 
Maybe this will do the trick. If not I will design a clamp for the to left corner of the right door. I noticed that the door itself is not rigid enough to hold a tight seal. I can adjust the hinges to where the top left of the right door touches the face first. But as I tighten the clamp I can see the door just bends and doesn't give the top of the stove the ultimate seal I need.

I may design something similar to a metal cabinet . Where u have a bar off the main clamp up to a hidnge point for a second clamp. Either that maybe just beef up the door so it doesn't flex so easy. What do you guys think?? Well Im guessing you think I'm crazy
 

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Guessing your secondary burn output may be outperforming the original stove design limitations:eek: If that's the case you may need to tame the beast in some fashion. Possibly reduce the effective secondary action somehow? Dunno.
Rather uncharted territory. Be safe either way!
 
Guessing your secondary burn output may be outperforming the original stove design limitations:eek: If that's the case you may need to tame the beast in some fashion. Possibly reduce the effective secondary action somehow? Dunno.
Rather uncharted territory. Be safe either way!
I had this problem long before I put the secondary tubes in it.

Back before I modified the primary intake to shut the stove down much further than factory set, with only 3 peices of wood the face would warp. 5 peices was out of the question
 
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