I have a question about how the burner/vaporiser works on an Optimus 111B. There are only two tubes, one seems to connect directly from the top to the spirits cup for filling the spirits cup I would assume. The other seems to be the vaporiser that rises from the fuel tube and connects to the flame adjustment valve. My question is how does this work? With just one tube connecting the fuel line to the burner head, which seems to have three branches that dead end there, how does the fuel flow? Anyone have a diagram or cut burner that would illustrate this?
I guess I was under the impression that the tubes are there just to hold the flame spreader up and fuel flows straight to the jet and never rises up above there, similar to an 8R stove. sam
Others are definitely more knowledgeable, I'm > IFFY on 111's. "Safety first" and you may already be aware but > IF not search 111B NRV. Ok re your question you may have read this but > IF not it may shed some light on it. https://classiccampstoves.com/posts/155346
Hi CJ1, Well observed. The vaporiser tubes are not actually used for fuel vaporisation/transfer on the 2-tube burner of the Op.111B. Fuel exits the jet, mixes with air and impacts the vaporiser chamber, which only acts as a flame plate. The two "vaporiser" tubes form the support to hold this "flame-plate" in position, and locate the flame ring. One of these tubes is also used to direct priming alcohol into the spirit cup before start-up. Have a look at this old thread: https://classiccampstoves.com/posts/87293 Best Regards, Kerophile.
Hi "OldManColeman", Yes I did read that post before. The old 111B without the hole and all four connectors may circulate the fuel but as for the common "T" top with the spirit hole clearly there is no path. I replace all the NRV rubber PIPs with new ones from "The Fettle Box" along with the cap gasket and the SRV (Safety Release Valve) PIP whenever I get a used or old stove. I also check my SRV BEFORE every use just to be sure it moves. Safety doesn't come from neglect.
Hi "Kerophile", Thanks for that thread, it was a good read. I would like to see a cutout down the middle of both pipes (or an actual engineering diagram) to really see what is going on. If the other tube is hollow as well, is there some kind of thermal circulation going on (any thermodynamic engineers out there). If it really is just a flame spreader like the 8R, shouldn't we be able to drill out the centre and put a "silent cap" on it? Ideas anyone? Chris of the North.
Hi Chris , why not provide a contribution to stove knowledge by providing photos of a sectioned Optimus 111B burner? I am sure the CCS members would appreciate the effort. On the subject of converting an Op. 111B to take a silent burner, I guess it could be done. However, why reinvent the wheel, when silent Op 111s already exist? Have a look at this thread about an Enders gasoline fuelled stove to see how a simple basket type burner can operate in either roarer or silent mode: https://classiccampstoves.com/threads/8075 Best Regards, Kerophile.
If I had extra or broken 111B burner I would. As for re-inventing a quiet 111 its just a question of cost. A 111T (or 111C) are in shorter supply and command a very high price when compared to the 111B. Also I have a few 111B that I'd like to tame and finally BernieDawg threw down the gauntlet when I asked him about a cap to tame the 111B when I purchased on for my 8R. Can I convert a 111B in to a 111T just by swapping the burners? Hey I've just been infected with the stove bug and I have a lot to learn.
Hi Chris, Welcome to CCS. I was only teasing! The answer to your question about the conversion is; YES, https://classiccampstoves.com/posts/275284 Best Regards, Kerophile.
CJ1 said: Huh? (Honestly, I don't own nearly as many gloves as people seem to be crediting me for.) Anyway, that's not quite how I remember our exchange in PT a month or so ago, Chris. You asked me about BD caps. You asked, did I have a design for both the 8R and the 111B. I said I did for the 8R, but that the 111B is a completely different burner design from the 8R. I explained that I designed for burners that have burner bells. The 111B and similar burners have an overhead vapo chamber. It's heated by direct application of the flame. I told you I didn't know how to make a burner for that overhead vapo chamber burner design. You seemed somewhat dissatisfied with my answer and went on to explain to me how both the 8R and the 111B operated on the all the same principles, etc, etc. I suggested to you that if you saw a way to make a silent cap for the 111B, you should try to design one because it would make you a million bucks. It could be used on all the other burners of that physical design which number in the thousands (millions?). I haven't figured out a way to do it myself or I would have done just that (made a million bucks). If you were able to come up with a working silencer for the 111B burner design that required no modification of the burner I would be the first to buy one from you. Maybe you could try Kickstarter to get funded. In the meantime, I'll stick with the 111T as Kerophile has graciously suggested to you. I have a few of these excellent 111T stoves and they really aren't that hard to find. They also aren't getting cheaper, so grab one now and sell it for more later. Try eBay and other auction websites, or, as Doc Mark would likely say, get out to flea markets and garage sales and you'll be sure to find one for under $20 in no time at all. Good luck! Cheers, Gary
Hi Gary, BernieDawg said To me that's a challenge and I love a challenge! But really I could clearly see that I need to lean how these stoves work and with the way they are constructed I can't take it apart to see how it works. The way the 111B burner is designed I just couldn't figure out how it was working, two tubes only one connected to the fuel and that "T" at the top, what is that for? An 8R is simple, easy to see how it all works, and with your BD Cap my 8R is great , thanks for that. I did finally find a 111T but it was more than a 111B. It is in need of some TLC to bring it back to life. BernieDawg said: Sorry Gary, it wasn't that I was dissatisfied with your answer, I just have trouble understanding how it works and not understanding is dissatisfying for me.
Hi Chris. The Op. 111 came before the Op.111B Some people ran the Op.111 with gasoline fuel, quite successfully. Optimus decided to make and sell the Op.111B, designed to run on Coleman fuel and probably aimed at the US market. I have always considered that they decided to do this with minimum change to the design and appearance relative to the Op. 111 model. The Op. 111B was built from the Op 111 parts bin and at first glance the burners look the same, however the Op.111B has only two tubes, and as you now know, is essentially a flame-plate design, with the former vaporiser tubes acting as support members for the flame-plate and flame-ring One tube is isolated and used to feed meths to the spirit-cup. The other is connected to the tube built into the vaporiser top but it has a blind end. The former vaporiser tubes probably do conduct some useful heat to the fuel feed but certainly one of them could work equally well as a brass rod. It would of course be more expensive and wouldn't meet the "minimum change" criteria, which I suspect Optimus specified for the Op 111B design. If Optimus had wanted to they could have fitted an enlarged version of the basket-type burner used on the Op.8R. However I think they wanted to maintain a consistent appearance for the Op 111 stable. If they had fitted a basket-style burner it would, of course, be much easier to adapt to a silent version! That's my reading of the situation, but I could be wrong. Best Regards, Kerophile.
Wow! Nicely done, Master Kerophile. That is in essence what I was trying to convey to Chris in PT, but, apparently, failed to do properly. No worries Chris, and no apologies needed. I tried my best to impart to you what the differences were between the 8R and the 111B, but apparently couldn't explain it as well as Kerophile now has accomplished.
Morning, George, I think your interpretation of how and why all this came about makes plenty of sense, and is very probably as close as we'll ever come to knowing the actually situation when the 111B was designed and offered. And, yes, I absolutely believe that the 111B was designed for the US market, and had it been actually pushed and better marketed by Optimus, I think it would have been far more popular than it actually was. However, the "B" did get some strong attention from certain types of campers, like expedition leaders, and canoeists. And, it was in those venues that the 111B seemed to find a home here in America. Thanks for sharing your thoughts on all this, and as usual, I do believe that you have thought it out very well, indeed. Take care, and God Bless! Every Good Wish, Mark
Thank you George, that does make a lot of sense. One thing I have found to be certain, the 111 breeds when it gets home. Like the old Lay's Potato Chips advertisement. "Bet you can't eat just one". Try to limit yourself to one 111. Ken in NC
I only wish Optimus had used a Coleman style NRV on the 111B. Much safer than a bit of cork, or whatever!
I wonder how hard it is to convert the pump to a screw down type safety valve or if its practical to make a tube that attaches to the bottom of the pump to take the pump outlet to above the fuel.
Fantastic! You guys are a wealth of information. I've been looking at the photo gallery for 111s and I see some 111s with a hole and others with a full X (in comparison to the T and a hole). On the 111 were there four tubes, one for the meths and three for the fuel? On the 111T I see all four connect to the same (hollow?) ring which looks like the fuel is heated directly. The explanation from "Master Kerophile" seems to answer the odd twin tube design. The design seems susceptible to losing the skirt and/or flame ring which would render the stove unusable. On the 8R, 99, etc. the flame spreader can be clamped down on the bowl where it can't fall off and get lost.
