Old roarer burner heads

Discussion in 'Fettlers Master Class' started by shagratork, Oct 23, 2007.

  1. shagratork

    shagratork United Kingdom Moderator, R.I.P. Subscriber

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    Gary
    Sounds exactly what is needed - I will keep a look out.

    Keith
    You are right about not needing a perfect seal. I was thinking of some sort of Chieftain seal held in place by jubilee clips.
    I need to buy Gary's compressor first to see what extra bits I need.
     
  2. fyldefox

    fyldefox R.I.P.

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    Sounds good to me Trevor . . . . :D
     
  3. Kenh157

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    People

    As has been previously mentioned, be safety conscious on a project
    such as this.

    We are considering to

    1. Heat a soldered burner head with a torch.

    2. Apply air pressure.

    3. Burn out carbon under pressure.

    Supposing a soldered joint gives way under heat and the whole works comes
    apart in your face ?

    I am not saying do not use this method -- JUST BE CAUTIOUS.

    Thanks for my rant,
    Ken H.
     
  4. barrabruce

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    After the head glows red I mean red the silver solder /brass brazing will melt. In the case for brazing it will be very close to the melting point of the brass anyway.

    I think the worst bit is when you cool it rapidly. I think the stresses can be relieved this way and twist a bit but worse is the shock to the jiont and different shrinkage of the metals causing cracking of the joint.

    Be hard pressed to blow off a burner head from its tubes.

    With any metal heating one should wear a good set of safety galsses but I suppose a shield be even better blowing red hot carbon bits around and such.

    Apparently they can't do much with stuffed eyes yet.


    Barra
     
  5. spudz

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    Do you have any knackered donor stoves ?
    Could the complete riser tube be taken from the tank, would that be 4 - 5 inches high, with the burner then attached and the air hose connected to the other end ?
    Would that provide enough 'safety' to not melt the air hose ?
    Riser tube could be held in a vice or similar, which might act as a pseudo heat sink ? :-k
     
  6. kerophile

    kerophile United Kingdom SotM Winner Subscriber

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    Hi, If you take Spudz' suggestion to its natural conclusion you would utilise the whole "donor" stove;

    1. Wash out the tank, as you are going to use this as an air-reservoir.

    2. Fit the filler cap with a Schrader valve or similar, as you are going to connect the bicycle pump to this.

    3. Fit the partially blocked burner to the stove in the conventional location.

    4. Pressurize the tank with air.... but don't over-do it!

    5. Heat the blocked burner (from which you have removed the jet) with a blowlamp or torch. Allow the air from the resevoir to flow through it. You will need to keep pumping, either manually or with an electrically-powered air compressor.

    6. The modified donor stove should be well able to handle the heat without modifications. Once the carbon inside the burner starts burning it should be possible to reduce the heat input from the torch or blowlamp.

    What do you think?

    Regards,
    Kerophile.
     
  7. oops56

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    To much heat and the tank will come un soldered put tank under water just leave valve stick up
     
  8. kerophile

    kerophile United Kingdom SotM Winner Subscriber

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    Hi Robert. I don't think the heat will be a major problem but it could be treated using a traditional radiation shield, or pie tin with a cut-out, located on the spirit cup ot on top of the tank. That would be a lot less messy than working with a water bath or puting a wet towel on top of the tank.
    Best Regards,
    George.
     
  9. fyldefox

    fyldefox R.I.P.

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    Interesting thoughts Spudz and George

    I reckon it comes down to how many hands you have available. Could be tricky applying heat with one hand holding a blowie, and pumping with the other, even with a track pump that you hold down with your feet.

    I have also found a pair of tile cutters in the garage which are like a pair of scissors but with flat pieces at the end. I reckon you could connect the air input to them permanently and use them also to hold the burner, so one hand holds the work and the other the blow lamp.
    Still working on how to make it reasonably air tight and to take a range of burner sizes . . . . some sort of taper fit ?
     
  10. sefaudi

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    Hi All,

    I see very interesting discussions are being made here.
    Instead of applying heat to burner may I suggest you something different?

    My proposal is simple. Put the burner into a reasonably large cap filled by a vinager. And get a dedicated aquarium pump to feed vinager into the burner. If the burner is not fully blocked then we should get a cycling.

    I did not tried this method yet but have been thinking on it for a long while. To this end I had also bought a little pump driven by drill. But I do not know why I have not put this setup into operation yet :shock: .


    Regards,
    Sefa
     
  11. kerophile

    kerophile United Kingdom SotM Winner Subscriber

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    Hi , There are three basically different methods of un-blocking burners being discussed in this thread:

    1, Heating the burner to a high temperature and quenching into water or other solution.

    I am not in favour of this approach, although it has been widely used, because of the danger of melting the braze which holds the parts of the burner together, and because you lock stresses into the metal structure and possibly cause distortion.


    2. Heating the burner( after the jet has been removed), to a high temperature and then passing pressurised air through. The principle is that the carbon crust inside the burner tubes is ignited and burns away to give clear tubes.

    Again with this method you need to be careful not to melt the braze. Once the carbon ignites the reaction should produce lots of heat so you can perhaps remove the torch or blowlamp being used for heating the burner. However, unlike the quenching method , there should be less stresses in the burner structure.

    3. "Pickling" the burner in vinegar, citric acid, or other corrosive solution.

    The principle here is that the acid penetrates between the carbon coating and the metal of the burner tubes, loosening the carbon and allowing it to be removed. The acid does not dissolve the carbon coke, which is relatively inert to these solutions. This is a cool treatment and does not introduce stresses. However, as with all pickling you need to be careful not to leave the metal in the solutions for too long, because you are corroding the metal. In the case of brass you may selectively remove zinc from the metal alloy.

    All three methods can be made to work. The choice has to be down to the collector.

    It is interesting however that the stove manufacturers chose the "burning" method for cleaning out choked burners.

    Best Regards,
    Kerophile.
     
  12. redspeedster

    redspeedster United Kingdom Subscriber

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    Hi
    I was thinking of a low tech approach. clamp burner in a lab stand, heat with blow torch until fairly hot, shove blow off gun up its rear end and let rip with the compressed air (always wear your P.P.E.). You could form a kind of tapered bung on the neck of the blow off gun to seal better. I thought of fiberglass stove pipe packing wound round or just a bored bung made of cork (might last a couple of goes). I'm not sure a perfect seal is required. Can't do a test of this set up coz all my burners are clear :roll: :roll: .
     
  13. David Shouksmith

    David Shouksmith Subscriber

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    Yes, which is why heating the burner whilst blowing air through it clears the deposits within - the carbon oxidises to carbon dioxide...

    Trevor, I've a compressor which you can use - it came from one of my favourite German supermarkets for a very reasonable price. It will also carry out many DIY / car-related jobs, too... 8)
     
  14. shagratork

    shagratork United Kingdom Moderator, R.I.P. Subscriber

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    Hi David

    Your offer of the use of your compressor sounds great to me - it is all the connecting bits and pieces that need sorting out. I will have a look at your compressor next time I visit Chez David.

    As for which method to use for cleaning the carbon out of the burner tubes, Kerophile has stated them clearly and eloquently.

    I described what I used on an 84 year old roarer-burner which was totally blocked.
    The citric acid soaking did nothing but block the burner even more.
    I tried to force air through the burner and nothing came through.
    I tried poking a wire down the tubes but I did not get anywhere with that.

    That is the main reason I resorted to the heat-and-quench method.
    I am aware of the caution which friends are saying about melting burner joints, but I don't heat the burner up to very high temperatures.
    You must also remember that burners operate at high temperatures in normal use, as illustrated below:

    1400868660-Primus_2.JPG

    1400868670-BigBurner.JPG

    Anyway, in the future, for non-blocked burners, I am hoping to use the method favoured by the Swedish stove manufacturers, which is to force air (containing oxygen) through the burner head while heating the burner with a blow-torch.
     
    Last edited by a moderator: Jun 26, 2015
  15. barrabruce

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    You don't need to seal the end. But you will get a bit of back flow which is heated by
    the end A wet rag wrapped around the nozzle did it for me but my air gun is mostly metal thou.

    How a bout a spare type and a line feed off that...I used to have a very small model srpay gun which I used to run off a car tyre..Think I got 15 minutes at least out of it before the pressure got to low.

    Just a thought

    Barra
     
  16. nagant

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    I'm really new at this but how about carburetor cleaner? either add some to fuel or spray can when disassembled. on old electric fans with brass parts i use some pretty wicked chemicals to clean. as long as you don't leave them on to long and rinse well I've had no problems. Great pictures Trevor! :)
     
  17. Diesel

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    Shagratork , I think your way was effective and ideal. I used a compressed air hose blow gun and a propane torch to do the same thing on my Burmos . With the jet removed. That Primus setup looks like the museum piece. It is a great photo of what goes on inside a burner. Thanks.
     
  18. shagratork

    shagratork United Kingdom Moderator, R.I.P. Subscriber

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    Hi Diesel

    I am pleased that you have been successful.
    If you do another burner, is there any chance of some photos??
     
  19. exeter_yak

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    Nice thread,
    I had totally missed this one until it was linked for me to see in a much later post by Kerophile. Nice work Trevor, (and all other contributors).

    I like the model #2 stoves, not only are they brutally big, but they work well for outdoor cookouts.
    Regards,
    Doug
     
  20. DocDenzler

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    Thanks, Thanks, Thanks,

    after several trials with different chemicals i finally used your "heat and quench method" exactly as you decribed for my Juwel #1 burner. It was totally blocked.

    And it worked perfectly ! :clap: :clap:

    Now my wonderfull Juwel #1 is equipped again with its own Juwel marked #1 burner.

    Thanks for this perfect tip !

    Regards

    DocDenzler