3” boiler project.

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Just while I am on... Does anyone have a 6" diameter vertical boiler in need of a burner? I made one because I saw the 135mm diameter ceramic on E&@y - and couldn't resist the challenge, but it is a 1/4" too large for a mate's boiler. So I'm selling, now I have made it work. Jetted for Butane, or propane regulated at 20psi, or Butane Propane mix if I change to a smaller jet (for the 25~30psi of the B-P mix). I shall put it on E&@y soon, anyway. It just needs a good home...
K2
 
I am looking forward to running the boiler once I finish the viewport. The burner was certainly one of the more interesting parts of the project. There are some really frightening videos of homemade burners so I thought I’d better get some advice. I meant to ask you what you what adhesive you used. After I get the wood installed I will spin decorative caps to cover the edges. Should give it a clean look. I also spun another burner base to build the second version you posted. I have a horizontal engine to build and I suppose I will need a horizontal boiler.
 
Hi Doug, Yeah... I can see never ending lists and plans at my end as well! I think you'll manage OK to make the longer rectangular burner for the horizontal boiler.
When you ask about adhesive, I assume you mean for the wood cladding?
But if your question is for the ceramic to can, I first seal at the lower (cooler) edge with silicon seal, then protect that from flames with car exhaust sealer - it doesn't crack as much as fireclay. But fireclay will do.
For cladding the boiler: my Multi-layer system is really held together with brass bands as much as anything. But here goes!
  1. A sheet of good paper, then Aluminium foil to boiler, I use paper "stick" glue - like a white lip-stick type of thing - or aerosol spray gum. You can use Celotape (Celophane sticky tape) or parcel tape as it is just to hold it for assembly. - Then more of the same to apply the corrugated cardboard and a top layer of Aluminium foil. A final sheet of paper around that makes it tidy.
  2. Now here's something I haven't tried, but should help prevent the wood cladding from sticking to everything beneath. I'll explain in a bit. If you wrap as single layer of cling-film, or polythene around the outer layer of paper, any glue from assembling the wood strips to the boiler won't stick.
  3. I have made some cladding as a "solid" tube, that will have to be cut-off if ever I need to remove it, but I have also made some cladding into 2 or 3 pieces of "shell" so when I remove the brass banding, the shells come away cleanly leaving just a paper wrapped insulation beneath. It makes it serviceable.
  4. So having built-up paper-aluminium-corrugated cardboard, paper - aluminium - paper and then the "non-stick" layer of plastic film, you can assemble the wood strips on top - held temporarily using rubber bands or string. I glue each strip in place when I am happy, by only glueing to the adjacent strip. The first strip tends to be the one adjacent to the water gauge. The second onwards working away from that side. At any other external part I make a break so the shell ends there. I continue from the other side of the obstruction with a new "shell". When I have all the shells made, I then add the odd bits to fill the gaps - e.g. behind the water gauge - but only stick one side to one shell, then when finished shells can be removed for any finishing etc. off the boiler, or for future maintenance. I use ordinary modellers sand-able PVA to assemble the strips into shells. I assemble and glue in situ when I have made all the strips. A bit of a messy fiddle with sliding them beneath rubber bands, when I have glue on the one already in place. This way you can check and adjust "by eye" in case you start to develop a twist in the vertical lines of the joints.Before the glue sets, I run a knife point up each joint to clean the excess glue away, and make a slight indentation in the "de-burred" wood strips. Because I always forget to chamfer them slightly beforehand! Of course, you can work-out a better process!
  5. When the glue has dried/cured, you can remove the "shells - and the plastic film beneath - and fettle them to your satisfaction. I re-fit them for sanding level, as the boiler provides suitable support while sanding. But then I have to clean the sawdust off the boiler.
  6. I stain and varnish in situ, then realise that all the splashes on the boiler are messy and take longer to clean off than is sensible. So maybe you want to stain and varnish the shells off the boiler?
  7. After finally fitting and fiddling with the shells, I make 2 brass strip clamps to hold the cladding in place.
  8. Finish lagging.
  9. After assembly and main lagging, all the odd short bit of copper and brass that I can sensibly lag get covered in carefully wrapped cotton string . Ends of the string can be held with a dab of glue, unless you can do proper whipped hidden tails.... Sailors know lots of ways of making "blind" ends that are neat, so you can't see the ends of the string! Paint the string with household white emulsion paint, and the finish will be representative of "asbestos lagged" industrial pipework. And it will reduce heat losses, especially on pipework to engines. It's a nice therapeutic job I think?
  10. The one pipe you do not lag is the pressure gauge siphon tube. This is designed to condense some steam into a water-trap so steam does not enter the gauge and affect it with excessive heat. This is the only bit of brass left for polishing on my boilers. (I don't polish much if I can help it! - It tarnishes quickly when I raise steam.).
Hope this helps?
K2
 
This will certainty do the job. After test running the boiler, I can appreciate the idea of not burning my fingers with the added benefit of heat conservation. I’ve seen several examples of people planking their boilers, but this is the first time I’ve seen it done with efficiency as a primary design feature. The tiny rivets just showed up so I’m off the races building the viewport and cutting mahogany strips. I’m using wood from a 3x4’ section I replaced from the bottom of the Tollycraft runabout. I find that the grain in the old wood had a unique pattern once you cut through the rot. Thanks K2
 
Need to do some clean up and polishing. The viewport is threaded and will,screw into the boiler to light and monitor the flame. I need to add a latch.
 

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Seems to work fine. Did not need a latch. The hinge is tilted so the door falls closed. I need to find a less clunky looking regulator and a model sized propane tank.
 
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I did a run up to see how the burner performed and if I liked the viewport before cladding. The boiler built up steam quickly and flame appears nice and even across the ceramic surface. The insulation layer is now complete and today I add the planking. The bull’s-eye lens worked out nicely and the port threads in perfectly. I’ll will post the completed boiler once I finish the woodwork.
 
Planks are installed and I am checking the fit before doing a final clean and polish. The plank end covers were spun using brass shim stock. It needs the planking extended through the base. I’m worried about scorching in the firebox area and was thinking a base layer of cylinder head gasket material might be an option.
 

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Hi, I use a black paint, or "silver" paint (for tarting-up car wheels).
Has the copper tarnished with heat?
Check how hot it gets... e.g. wipe a line with a candle - to check a "Wax melting" temperature - when enamel paint bakes hard - then soap - as this turns black at "Aluminium annealing" temperature, when paint burns-off. If you "tin" a couple of dots with solder you can exactly determine if you reach >165C. - or whatever melting point of your solder. Or wipe with a bit of polythene, or PVC - if you know the melting points of those. Everything from Ice upwards is useful for checking temperatures.... even thermometers... If the base has a space where the ceramic fits, then it will get HOT! But if only space below the ceramic where gas and air mix, then it won't need heat resistant gasket paper - in my experience. Really, Matt Black paint is best to keep it cool below the ceramic plate. - Try just blackening it with charcoal? or Blackboard paint? (If it is politically correct to still buy it? - In the UK we should now call it "chalk-board" paint - but that is now green (and therefore environmentally OK?) in many instances! - Sorry, I am going a bit "mental" with "political correctness"!).
A great looking boiler! - Well done!
K2
 
Hi Again Doug.
Just an observation... In case you are going to take it somewhere for certification.... I understand that it is NOT normal practice to situate the SAFETY valve on the steam outlet. So the Tester may no
I shall explain:
  • The SAFETY valve is to prevent the boiler from excessive pressure.
  • The steam take-off shall normally be situated at a different point, in case of a partially blocked or limiting steam collection point.If there is such a partial blockage, then the steam take-off line can realise a pressure drop from "boiler space" to where the SAFETY valve is located, depending upon how much steam is flowing in the steam take-off pipe. In this case, The boiler can realise pressures in excess of the CONTROL pressure that the SAFETY valve is designed to manage.
  • The SAFETY valve shall be tested at each steaming (once a day at light-up is normal practice).
  • The SAFETY valve should be kept away from extraneous heat, dirt or other factors that can affect its operation. (I.E. NOT in the smoke-box!).
I have highlighted certain words in capitals, as the meaning is paramount within the regulations.
  • Additionally: The steam-line from take-off point at the boiler may pass through a temperature raising zone, either for drying the steam, of super-heating the steam. This will change the pressure as seen by the SAFETY valve, when compared to the actual boiler pressure, that should be managed by the SAFETY valve.
  • Now there is a situation where a SAFETY valve can be in a line: e.g. where there is a high pressure feed and a pressure reducing valve to a sub-line, that must be prevented from some over-pressure. (In factories, I have experienced this where the main AIR-line is at a higher pressure, but certain equipment uses lower pressure air and as such need a pressure regulator to manage the sub-line. In this case, a SAFETY valve can be fitted to prevent equipment dames, of the line and equipment below the pressure regulator. BUT THIS IS NOT MEANT FOR BOILER SAFETY VALVES.
  • On one of my boilers, I have a "dome" for collecting the flue gases above the boiler proper. Within this dome there is a coil of pipe so the flue gases dry the steam that is passing to the engine. The SAFETY valve is set into a separate tapped take-off in the top plate of the boiler. The SAFETY valve passes through a tube that is fitted into the dome, so it is shielded and separated from the flue gases, and can relieve pressure directly from the boiler space to atmosphere. I'll try and get some photos for you. This is to comply with normal practice where the SAFETY valve shall be separately located from the steam take-off (for use of the steam) and unaffected by the boiler heating gases. Someone once told me that on his boat he had the safety valve inside the smoke-box, so if it blew-off the back-pressure of steam would extinguish the fire! - Then he filled the boat with gas... with the ensuing explosion risk! He changed it when I suggested that latter risk...
Sorry to put a bit of a "damper" on an otherwise excellent boiler. I didn't see that glitch when I was blinded by the brightly polished copper... It isn't obvious from the pics how the steam take-off and SAFETY valve mounting have been managed in the early pictures. But "somehow", you go from these bits to a pipe sticking out of the side of the boiler with the steam control valve on it. Please can you show us the boiler top beneath the "trumpet-bell" smoke-stack?
Thanks,
K2
1619425753987.png
 
Hmmm... With 13 tubes, there is no space to put a blowoff valve. I have the whistle on it’s own outlet. It makes since that the relief valve would see a pressure drop in line with the accessories it powers. My original thought was to place the relief valve on it’s own dedicated port where the whistle sits. I did not catch this in the reading. Time for some more reading.
 
Hi, I use a black paint, or "silver" paint (for tarting-up car wheels).
Has the copper tarnished with heat?
Check how hot it gets... e.g. wipe a line with a candle - to check a "Wax melting" temperature - when enamel paint bakes hard - then soap - as this turns black at "Aluminium annealing" temperature, when paint burns-off. If you "tin" a couple of dots with solder you can exactly determine if you reach >165C. - or whatever melting point of your solder. Or wipe with a bit of polythene, or PVC - if you know the melting points of those. Everything from Ice upwards is useful for checking temperatures.... even thermometers... If the base has a space where the ceramic fits, then it will get HOT! But if only space below the ceramic where gas and air mix, then it won't need heat resistant gasket paper - in my experience. Really, Matt Black paint is best to keep it cool below the ceramic plate. - Try just blackening it with charcoal? or Blackboard paint? (If it is politically correct to still buy it? - In the UK we should now call it "chalk-board" paint - but that is now green (and therefore environmentally OK?) in many instances! - Sorry, I am going a bit "mental" with "political correctness"!).
A great looking boiler! - Well done!
K2
It does tarnish, but I wipe it down after use then use a polishing cloths do it cleans up nicely. This is just cosmetics and artistic balance.
 
Hi Doug. I don't know the size of ports for the various fittings. But using the port for the whistle would be quite alright as far as I can tell from here.... Then put the whistle where the Safety valve was situated? - I assume the right-angle fitting opposite to the pressure gauge is the "whistle" point? I am guessing it will be big enough for the Safety valve.
1619451957235.png

Maybe you can give me the length and ID of the 13 flue tubes (I know the boiler is 3inches diameter but only have your pictures to estimate sizes) and can you confirm that it is essentially a flat bottomed water tank with the flue tubes in it? (not a water-jacketed skirt around the burner).
What size is the clear bore of the hole where the whistle fits?
What is your Normal Working pressure?
Incidentally, do you have calculations for the strength of the boiler - needed for certification if not a "proven" standard design? (I.E. if someone has published the design somewhere - like in a book - and it is known to be certified and OK).
I am currently doing some calculations for another boiler maker - and want to check on "other calculations" - if available - to see where I am right and where I am wrong! (I call it "the Einstein principle" - he did it all the time!).
My initial guess is that you have 13 tubes, 1/2" bore, 9" long with the base plate heated - makes 184 + 4.5 ~190sq.in. heating surface = at 50 psi you should have a safety valve connection bore of 1/4" - or whatever. This could result in something like 500psi stress of the flue tubes, which is less than the 837psi stress permitted for copper in compression - according to some calculations I have seen. But I'll be glad to "see yours"?
Ta,
K2
 
Will do after I get home. I find myself making a list of things not to do for the next project. I need to retire. Work gets in the way.
 
I did another measurement of the materials used against my initial measurements.
Water area: 2.945”id X 6.5”
Boiler shell: 0.0895” thick
Boiler caps: 0.0453” thick
Tubes: .5”od wall thickness 0.0452”
Nominal working pressure 35psi. (My engines run on lung power)
Blowoff valve pressure 50psi.
Port1 id- 3/16” where blowoff is currently located
Port2 id- 1/8” where whistle is located and is the id of the engine inlet.
 
Hi Doug.
I have only been retired for a couple of years - but work seems a lifetime away.
I suggest to all "approaching retirees".. like yourself.
Make sure you have 3 things that you have been enjoying (within the limits of what can be done in life).
  1. Companionship: The dozen or more people you spoke to from leaving for work to returning won't be there every day... So develop some more contacts in your hobbies and expected retirement occupation(s) so you don't feel "alone" when you retire. (My sister collects her newspaper - and her neighbours', every day instead of getting it delivered. That gets her out, and she meets the people daily, in all weathers, if only for a few words. She couldn't do that when rushing off to work every day! Little things make a significant difference.)
  2. Rewards: Salary becomes Pension. But costs change as well. Commuting costs disappear, Heating costs go up... (not using "the workplace hot air" to heat your body!). Etc. But the rewards of completing whatever it is now each day will disappear... so you will need a new something to fulfil your ambition each day, even if the rewards take a new form. My new "rewards" come from finding a solution to "mechanical" problems, as in this chat line, amongst other things.
  3. Occupation: Having taken "work" away, you need something new to fill a big chunk of that time, as decorating and "following the Missus to the shops" will get tiresome. - And she will probably leave you! - She needs her life to retain her freedom, personal space, or whatever.
  4. Talk to your Missus about what she wants to do when you retire. - I didn't, and possibly things were a bit rougher than I expected for a few months, until we worked out how to be retired together. This stress is normal, but almost all relationships, built with half a lifetime's history, work it out.
Retirement is what most of us work for half our lives, and our bodies need it. But our minds need plenty of "brain challenges" to keep good, and happy. Maybe a bit slower, or need a bit more sleep, but still need the exercise.

Nuff said there.
I'll do some check calculations on the boiler later today (probably). Can the "whistle" take-off be opened out a few thou? - or a 1/32"? Check it and see how it performs "on full fire" with the steam take-off valve shut? 1/8" may be OK, as the fire and boiler geometry make a difference. Maybe use a stainless steel connector rather than brass, if that allows a larger hole? Can you set the Safety valve directly into the boiler hole? - It does not need to be vertical, but does need to be above where the water is frothing on the surface when boiling. It is designed to eject steam, not water. You can always fit a shroud to point the steam in a direction away from the operator. I have seen boilers that blast steam sideways, or vertically into the face of the fireman! = Not good! I sometimes add a large tube over a safety valve so any discharge goes to the top of the tent away from Joe Public (and my face) when I am steaming. My head is usually higher than the table where the boiler sits, and a blast of steam under the chin always makes me jump!
Regards,
K2
 
Hi Doug.
I have only been retired for a couple of years - but work seems a lifetime away.
I suggest to all "approaching retirees".. like yourself.
Make sure you have 3 things that you have been enjoying (within the limits of what can be done in life).
  1. Companionship: The dozen or more people you spoke to from leaving for work to returning won't be there every day... So develop some more contacts in your hobbies and expected retirement occupation(s) so you don't feel "alone" when you retire. (My sister collects her newspaper - and her neighbours', every day instead of getting it delivered. That gets her out, and she meets the people daily, in all weathers, if only for a few words. She couldn't do that when rushing off to work every day! Little things make a significant difference.)
  2. Rewards: Salary becomes Pension. But costs change as well. Commuting costs disappear, Heating costs go up... (not using "the workplace hot air" to heat your body!). Etc. But the rewards of completing whatever it is now each day will disappear... so you will need a new something to fulfil your ambition each day, even if the rewards take a new form. My new "rewards" come from finding a solution to "mechanical" problems, as in this chat line, amongst other things.
  3. Occupation: Having taken "work" away, you need something new to fill a big chunk of that time, as decorating and "following the Missus to the shops" will get tiresome. - And she will probably leave you! - She needs her life to retain her freedom, personal space, or whatever.
  4. Talk to your Missus about what she wants to do when you retire. - I didn't, and possibly things were a bit rougher than I expected for a few months, until we worked out how to be retired together. This stress is normal, but almost all relationships, built with half a lifetime's history, work it out.
Retirement is what most of us work for half our lives, and our bodies need it. But our minds need plenty of "brain challenges" to keep good, and happy. Maybe a bit slower, or need a bit more sleep, but still need the exercise.

Nuff said there.
I'll do some check calculations on the boiler later today (probably). Can the "whistle" take-off be opened out a few thou? - or a 1/32"? Check it and see how it performs "on full fire" with the steam take-off valve shut? 1/8" may be OK, as the fire and boiler geometry make a difference. Maybe use a stainless steel connector rather than brass, if that allows a larger hole? Can you set the Safety valve directly into the boiler hole? - It does not need to be vertical, but does need to be above where the water is frothing on the surface when boiling. It is designed to eject steam, not water. You can always fit a shroud to point the steam in a direction away from the operator. I have seen boilers that blast steam sideways, or vertically into the face of the fireman! = Not good! I sometimes add a large tube over a safety valve so any discharge goes to the top of the tent away from Joe Public (and my face) when I am steaming. My head is usually higher than the table where the boiler sits, and a blast of steam under the chin always makes me jump!
Regards,
K2
I am basically becoming a reformed software and electrical engineer. I started working in 1982 with side businesses doing textbooks and running a clock and instrument repair home business. I am ready to retire.
 
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