Larger Moya???

Discussion in 'Burners and their construction' started by HT1, Jun 14, 2019.

  1. HT1

    HT1 Gold Banner Member

    Has anyone seen or heard tale of a Moya Burner larger then One Inch? I saw several people going smaller??? has anyone seen larger

    Thanks in advance
    V/r
    HT1
     
  2. Tobho Mott

    Tobho Mott Administrator Staff Member Banner Member

    That would be a lot like a Brute, no? In the same way a 1" Moya is a lot like a Hot Shot.

    Jeff
     
  3. What do you consider a Moya?
     
  4. Tobho Mott

    Tobho Mott Administrator Staff Member Banner Member

  5. DavidF

    DavidF Administrator Staff Member Banner Member

    Speaking of Moya, I need to see when he is coming to get his milling machine out of my garage....
     
  6. He says he patterned it after a Brute.

    My air comes straight in the back with a 90 on the oil line. Does that make it not a Moya?
     
  7. Tobho Mott

    Tobho Mott Administrator Staff Member Banner Member

    Like this?

    [​IMG]

    To me it's the air coming in from a tee that makes a Moya not a Hot Shot.

    Jeff
     
  8. Rasper

    Rasper Silver

    I extended the oil feed tube down to almost the end of the one inch pipe. Lionel said he had some problems with the pipe sooting up the way it is drawn.

    This is absolutely the best burner I have seen for a furnace.

    Richard
     
    Chazza likes this.
  9. I extended my oil feed just past the end of the tube. It's got a lot of hours on it.

    IMG_6079.JPG

    So the Moya is what somebody calls a sidearm burner?

    Is mine a modified Hot Shot?

    IMG_6080.JPG

    Pipe is 1-1/4" inside diameter so it's not a Moya over 1".:(
     
    Chazza likes this.
  10. Rasper

    Rasper Silver

    Looks like what you have is a Hot Shot Senior, or maybe a Brute Junior.

    These Lionel type drip burners just work, time after time after time. No clogged nozzles, no filters, no expensive air compressors to wear out. Just a 25 dollar shop vac, with another in reserve. The only problem I have ever had in six or seven years was when rainwater got in my oil tank. I just turned the propane feed back on and melted my bronze.

    Richard
     
    Chazza likes this.
  11. I'm using an $18 leaf blower with two speeds. But I had to make an adapter to get to vacuum hose.

    I have had to rod out my brake line a couple of times, but I melt several times per week. I couldn't be happier with an Uber Hot Shot. It was just the size pipe I had handy.

    They put oil and air into the furnace. That is what it takes.
     
    Chazza likes this.
  12. HT1

    HT1 Gold Banner Member

    well Lots of Talk about burners, No answer to My question though, so Let me tell you what is going on, Im going to build a new furnace and burner in the near future, I have been running a Moya on Propane only for three years now , I would like to trim My melt time down to Mifco's mystical 35 Minutes on natural gas or Propane, I think a larger burner would be advantageous, but would still like the Capability to Switch to oil in case the world ends and I need to do Cast Fe, But if no one has done a LARGE Moya, I may just go to a straight Propane and Blower rig, and if I have to do oil i'll have to make some sort of adapter for my Furnace inlet

    http://www.alloyavenue.com/vb/showthread.php?12550-HT1-s-Moya-Burner/page4&highlight=HT1+burner


    V/r HT1
     
  13. Tobho Mott

    Tobho Mott Administrator Staff Member Banner Member

    I still say anyone who uses a Brute is basically using a larger Moya (or Hot Shot).

    [​IMG]

    Jeff
     
  14. And I don't claim my burner is a Moyer, but it runs fine on propane. You don't need a good burner design once you add forced air. Naturally induced burners need to be designed properly because you can only turn the air down with a damper. With a leaf blower or vacuum or other high pressure blower all you need is a long tube to let the propane mix with the air before it enters the furnace. My propane just tees into the burner tube with no nozzle of any kind. A needle valve controls the propane flow. Run a 1/4" propane pipe and forget sizing a nozzle if you're going to force air into it anyway.

    To start you need to almost shut off the air, then crack the propane (I use a burning wad of newspaper for a pilot). Once the propane is lit, up the propane, pour the air to it and shut the lid. I do have an advantage in that with my burner pointing down I can light the propane without turning on the blower. If the tube were level you could get propane backflow. I don't rely on gravity though because a sudden gut of wind could surprise me.
     
    Petee716 likes this.
  15. DavidF

    DavidF Administrator Staff Member Banner Member

    HT1, I'm not sure if your really need to size one up or not. I'm thinking the bigger issue will be having enough furnace volume to allow the waste oil to fully combust inside the furnace and not as it is exiting the furnace. This is not a problem with NG or propane as they enter the furnace in a gaseous state.
    So what crucible size are you planning on for this new furnace anyway??
     
  16. HT1

    HT1 Gold Banner Member

    I'm Sizing for 20-30 , I suspect I will settle on a 25 , I think that is the Biggest Crucible I can Handle with a safe Melt size, I currently run 16 s and fill them to the Brim.
    thinking Propane, not so Much about Oil I "believe" a larger burner running the same amount of air (the air will be moving slower), will allow the furnace to get hotter faster ( be more efficient) I still think we are blowing too much heat right out of the top of our furnaces without it having time to transfer to the melt
     
    Billy Elmore and joe yard like this.
  17. HT1

    HT1 Gold Banner Member

    [​IMG]

    I have not read up on this burner alot but it seems (having trouble with vocabulary) not right? I'll explain:

    1) but really if you need the taper at the end, why not just use a smaller pipe. oil and Propane should both burn outside the burner so about the only thing the taper might do is make the air turbulent , and there are other ways to do that especially in a 2 inch pipe

    2) why is that pipe 17 inches long ??? really is that critical? why ??? or is that just how long the Piece of scrap that was laying about was?

    3) the Moya does all of this Much more gracefully and if you made a Moya with an angled tee fitting it would be even more graceful ( BUT The 90 Tee would make for some seriously turbulent air that might be helpful)

    Visit here and take a look at this Propane Burner Note how he talks about a Flame holder, in a forge this might be an issue, but in a furnace where the tuyere is built into the furnace wall (cast ) in most cases, a flame holder should be unneccessary, but look down the end of a Moya look there is that Flame holder by design, that is why i'm wondering if a Moya can be scaled up and still burn propane well... yes I know I'm probably the only one using a Moya that way . But it works well, I would Just like to improve it
    http://gaijinto.blogspot.com/2011/02/propane-burners-old-and-new.html

    Here is a useful and necessary detail, a flame holder made out of a 0.75 inch tube held inside the bigger tube by radially arranged screws. Some people go without it, but I could not keep a steady flame without one.
    The flame of this one is massive, and by controlling the blower speed one can easily switch between an oxidizing and a reducing flame.
    [​IMG]
    [​IMG]
    [​IMG]
     
  18. Tobho Mott

    Tobho Mott Administrator Staff Member Banner Member

    I think some Brute users have done away with the taper at the end (J. Vibert IIRC, where's he been anyhow?), and I'm pretty sure the length is not crucial, I got the impression that diagram was just based on measurements Lio took off his Brute after he built it.

    I am not sure if the oil tube in my regular 1" tube Moya acts as a flame holder, as it won't run on propane in open air like the one in the pic. Been thinking about building one in a bigger tube too, for the big furnace. The 1" Moya was easy to build cheap using plumbing fittings for the tee etc., bit I've got leftover 2-1/2" and 2-1/4" exhaust tubing that already fits my furnace tuyere, maybe I'll start welding something up later when I get home.

    Jeff
     
  19. HT1

    HT1 Gold Banner Member

    UMM I'm being a little Posterior retentive, because I would kind of like to know how much of what we see is required and how much is "well Earl did it that way so we all did"
    Moya is probably the easiest burner to Build, it can be done with no welding and Powered with a Bucket Vacuum so $25

    I would like to seriously trim my Melt times not so Much because I need to but as it would be convenient.

    I wish we could do some real scientific experimentation I mean someone was talking about Ursutz burners, and Leonard dropped those 10 years ago after serious experimentation, and no I dont mind anyone else revisiting something but we need some scientific method...

    For example how much Propane will my burner use??? well I could throw the tank it on a scale when I start and when I'm done with a heat or just run it an hour the way I like to and we would get a Gal/hour which is easily converted to BTU/Hr, but there is no on the fly measurement.
    combustion air is more complicated , and really I have no idea how we could measure that , I'm really unclear about all the issues involved in air flow CFI and CFM etc. I think more air moving slower would be better, that is why i'm thinking larger burner old iron Farmer suggested a larger furnace, then we have more heat loss as an Issue .

    I originally was going to just move to an insulated furnace with my same burner to see how that improves things, but if I do just that i'm locked in at a 1 inch burner size, if I go to a Much larger burner I can go Back down with nothing more complicated then some cast refractory and Kaowool or even Just Kaowool and satanite

    I'm also worried about the Jet if you read my Build thread http://www.alloyavenue.com/vb/showthread.php?12550-HT1-s-Moya-Burner/page3
    I drilled a 1/16 jet for my propane to come in through... and I run My furnace at 25 PSI what will happen if I use a larger jet , probably nothing as I will get the same Propane with less Pressure ...

    well enough agonizing I'm going to go carve a pattern

    V/r HT1
     
  20. If you can weld, a Moya is more expensive given the cost of fittings these days.
    You could buy a flow meter, but it's really not necessary. Weighing the tank is pretty easy and is very accurate. With a 0.0625 diameter nozzle and 25 psi propane you would be burning about 10 lbs/hour if you don't have a needle valve slowing it down. That would be about 220,000 BTU/hour. MIFCO is burning a lot more.
    Combustion air is difficult to measure. If you can borrow an anemometer you can estimate the flow rate by determining the velocity.

    A larger furnace is not more heat loss if it is insulated better than a small furnace. Regardless, more fuel means more heat so long as the fuel is burned in the furnace. How well is your current furnace insulated?
    Unless your regulator is maxed out you're going to move a lot more propane with a little larger nozzle. The regulator will open up to give you more flow.

    If you don't want to change, don't change, but since you have forced air you can eliminate the nozzle and just use a needle valve to limit propane flow. You don't need to know combustion flow rate if you can adjust your propane flow and determine how much you can add with the air you have. Do you have a damper to limit air flow? If you're using the open distance from air nozzle to burner intake you already have an idea whether you can use more propane with your current blower. You might want to invest in a leaf blower ($20) and drill out your nozzle then use a needle valve to tune the burner. The vacuum I tried didn't put out enough air for me but the leaf blower does good. I think you can cut your melt times with more propane and more air. It's really cheap to try to push more air through your current burner and it might surprise you.
     

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