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More burner pics, per above discussion.
Close-up of a version of the "roaring" burner from K.N. Harris - uses Petrol, and because the air hole is on one side the flame is biased to the opposite side, not uniform. Actually quite a small burner, the 3" horizontal boiler needs a bigger flame than this can manage.
P8102451.JPG

A Paraffin/Kerosene proprietary blow-lamp converted to blast a flame beneath a 3" horizontal boiler - As good as these get, but a bit small. Good for a marine boiler fire-tube, with cross-tubes.
P8102452.JPG

2 of my 4 Regular blow-lamps, one petrol and one paraffin/kerosene, just sitting on the bench from a recent job.- can be bought for around £10~15 in the UK, and if any bits required for refurbishing pumps, valves, jets, prickers, these can be bought off £&@y easily.
P8102449.JPG

Sorry to be a bore to those who are not interested - but you have managed to read to the end of my thread...
K2
 

sutty

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All knowledge is good to me, especially when it’s free, I feel I should have learnt this 60 yrs ago but two stokes took over.

regards sutty
 
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Sorry to disappoint Sutty, my "knowledge" is just hard experience, & comes from "playing with fire" from being too young to understand the danger, and watching my Dad, Grand-dad, and others with various different types of camping stoves, using spirit, paraffin, Petrol, then being a student and using these stoves when I was camping! I quickly realised that as I carried a few gallons of petrol in the tank of the motorbike, that MUST be the best type of stove to have. And later as a Blow-lamp. Saved carrying other fuels is tins and bottles and running out!
Sadly, I have made a few dozen burners of varying types. My biggest a 10kW Propane gas radiant element 4" diameter and 4" high. Hot stuff!
K2
 

sutty

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Ken, do I need shoulders on the elbows for the superheater where they pass through the flue or will a decent fillet of silver solder suffice ? the elbows will be St/St and TIG welded together and soldered into the flue

Edd's took to the torch like duck to water, his first couple of practice beads were good, what do you use as a pickle bath ?

regards sutty
 

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Hi Sutty,
That's a neat layout, but the weakness in your design is the bush in the centre flue. Almost impossible to repair if not good enough first time. Personally, I would take the steam though a bush in the top plate (Which is the seal between the Steam chamber of the boiler and the Steam outlet, and being in the top plate can be a large bush with a good, accessible, silver-soldered joint) , loop it into the flue (through a hole that is NOT pressurised) down and up and out through the side of the flue away from the steamy bit of the boiler. That's the way I have done mine. Quite a faff getting the loop of pipe into the flue, then poking the ends through 2 holes drilled in the flue, but worth it IMHO. You can even arrange a joint in the flue at that point. Joints to the boiler steam take-off are outside the boiler (better for inspection and if any maintenance is ever needed). The interface between the stainless superheater tube and the connector (right-angle?) to the steam outlet on top of the boiler, can be a simple Nut and olive arrangement:
Vis-a-vis:
P8112463.JPG

(Sorry I don't do CAD - too slow!).
There are various ways of making the fittings to suit, so that can be whatever you choose (nut and olive, flanges and gaskets, etc.). But the principle is to keep the joints OUTSIDE the boiler shell. According to the usual principles I have experienced, superheaters and other fittings, etc. are considered "accessories" to the boiler structure, so if detachable, are not a part of the Regulation certification, although often are included in the hydraulic and steam testing (e.g. the syphon tube and the pressure gauge must be fitted for the steam test). Simply, if it can be removed and another fitted without destroying the integrity of the boiler they can leak! The inspector will just say "fix-it" and not deny the certificate on the boiler itself. (I have seen joints leak and a cracked valve casting fail hydraulic and steam tests - after all was good "on the bench": Conclusion, take the Bench to be tested!).
Glad Edd is taking to Lamp work. I pickle in a solution of "central heating de-scaler" - because I bought a big box of powder dead cheap in a sale. Citric acid (enough to make a full gallon of full strength) is a good cheap starter solution though. Or full strength Vinegar? Organic acids are simply a bit safer (and cheap?) compared to mineral acids.
Cheers.
K2
 

sutty

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Cheers Ken, more mods to come, better now than when it’s all made up. We can see the logic behind your design.
Edd’s away for a couple of weeks now so his brazing tuition is on hold
, his technique with the O/A torch seemed pretty fluent, he seemed to understand the temp adjustment between torch angle and distance adjustment to get the solder to flow where he wanted, going to cost me a bit in gas, metal and solder I think.

once again Ken thank you.

regards sutty
 
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Hi Sutty,
While Edd is away you can collect your thoughts on maybe structuring his education? Rather than just "well, this is the next bit, so how are we going to make it?", into "Right, we know silver soldering is a necessary joining technique, so here's how we design joints and the overall structure for silver soldering"? - now you have handled the tools and have an idea of what the finished job will be like. => This will lead you to designing jobs not just to be functional, but able to be manufactured... - which is what I have been focussing upon when teaching you the design aspects (but you had probably noticed that already! - Just print your designs and watch the evolution?).
All engineering is really a development process, starting with the "problem,", then progressing through ideas, on a lot of small "loops" of thought:
1 - What can fix the problem?
2 - how can I make it?
3 - That isn't good enough, how can I improve it?
4 - What do I need to change/learn in order to make it?
5 - Oh, there's a new problem, so back to 1 - !! - This closes the loop and while you seem to start again, it is like a man rolling a beer barrel up a ramp (pair of planks). The side-bung starts on top of the barrel (lying on its side) when he starts to push it. The bung actually drops lower, as the centre of gravity rises a bit, until it is at the point where it meets the ramp level, then rises until it is at the top again. But as the barrel has travelled up the slope, the bung has travelled up the same height above its original position - even though it dropped down - and is now higher than before. So the barrel is now at a "better height" and the bung has gone around a circle of development to get to a better height. Equally, "design and manufacturing" processes are like the "Bung and barrel". The design goes in a series of loops to get better, as the manufacturing bit gets better little by little on the way.
Maybe not the best illustration, but I am sure you can re-write it for Edd!

You'll quickly realise, that the "simple" boiler you first envisaged, has become a "proper" boiler, and you have learned "WHY" so many parts and features are "what they are", and "why they exist", and "how to make them within the finished design"....
No-one can design something without understanding manufacture, and no-one can just make something from scratch without designing it: - For purpose, for manufacture, for budget.

I am pretty sure that while you are patiently tolerating my long messages, you are enjoying the process of learning "boiler making" and a few other things along the way.
I'm just glad to help - and pass on some of my knowledge to the next generation...
Cheers.
K2
 

sutty

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Hello Ken, you are of course right about boilers, never had anything to do with steam or boilers but it’s an interesting lesson and I'm enjoying it.
After spending my working life as a machine tool fitter in all kinds of industries and manufacturing processes, most of the time solving the problems then building them out, I love the challenge.
my Motto is “ there’s no such thing as problems only solutions”
i’ve also trained lots of apprentices, although the last batch before I packed up are now all managers having left the trade behind, it's quite different having a 12yo apprentice.
I like the idea of the super heater being out side the boiler and am I right in thinking that when we present it for certification we can remove the super heater and plug the steam outlet !
Picked up a bit of 6mm stainless with a 1mm wall from our local metal shop, i knocked up a little bender to see if we could get it tight enough to fit the flue, which were going to split. It bent ok and it fitted like a glove.
On the look out now for ME taps and dies, something else i didn't know about.
Your help is most welcome and I make sure Edd knows that .
Here's a pic of the super heater.

Best regards Sutty
 

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Hi Sutty, Good work!
And Yes, if you feel it is appropriate, you can disconnect the superheater tube and blank it at the boiler steam outlet when you do the Hydraulic test. But I think it should be fitted for the steam test, as I always do that. There is of course a risk, that as the final outlet would be blanked-off, there is no steam flow through the superheater, effectively it is "uncooled" by the steam flow so will rise in temperature to the temperature of the flue gases. In normal use feeding an engine, it would be at a lower temperature than the flue gases, because the steam passing through is extracting that heat, but in both cases it will be in the flue and therefore imparting the normal constraint of the exhaust gases, which may be the limiting factor if the burner. To run without the superheater, has been done by some guys where I have watched steam tests, because they have to remove superheaters on Loco boilers to access the regulator to blank it off. And they don't want to risk overheating the superheater tube. But on your boiler I expect it to manage OK. But you can always prove me wrong! My philosophy is: "if it doesn't fail the steam test then something is right!" - And I like everything I put under steam temperature and pressure to be tested, so I can eliminate such failures before it goes into service.
A good question! Hope my "optional" reply helps you understand what you can do, so you can make a good decision, that works for you.
I like the way you "knocked-up a little bender"! Not everyone can do that and get the results you have in the photo.., Well done!
Also, using "domestic heating tube straight connectors" you may find a connector that makes a pretty joint between the flue in the boiler and the flue to Heaven?
I am looking forward to the next question...
K2
 

sutty

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Cheers Ken all understood. Your idea for routing the heater tube has saved loads of work, one bush in the boiler top instead of the 2 through the flue and the one for the outlet in the top plus I was going to Tig up 2 90 deg elbows

Best regards sutty
 
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No problems Sutty, I am here to help. But don't let me dominate. After all it is Your design and manufacture. Took me about 10 years to gain confidence in my boiler making. Even now I sometimes have doubts, but "teaching" is the best remedy, as when pupils challenge you they will usually find out your weaknesses or shortcomings. Which helps me get better. And I am enjoying your company (and challenges!) with this project.
Thanks,
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Me (again!): I had an idea, a photo speaks volumes... Here are a couple of proprietary connectors used on a flue pipe. First the steam pipe disappearing down the flue to the firebox as a superheater. And the top flue with proprietary connectors:
P8122443.JPG P8122444.JPG
Assembled:
P8122445.JPG

And one extending a flue:
P8122449.JPG
Sorry for the dusty boiler, it hasn't been "in steam" (cleaned and polished) since last year...
And a few posts back we were talking about water gauges: I mentioned that if not directly connected to the boiler side bushes, then the water level can be affected by the small bore glass of the gauge (especially at lower pressures) due to the surface tension dragging the meniscus up the glass, giving a False reading.
The countermeasure is a larger bore by-pass tube: vis-a-vis:
P8122446.JPG

You may also be able to see how the blue diagonal lines indicate water level - or in this case of a blown-down boiler there is a lack of water level - because without water the lines carry-on in the same direction, but if there was water in the gauge the lines would appear to be in the opposite slope to the diagonal as drawn. The hatched lines need to be about the same distance from the glass as the diameter of the glass tube.
Cheers!
K2
 
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Hi Sutty,
I have never worked it out, but possibly it costs more for Silver Solder, gas etc. than for copper in a model boiler...? But Commercially, time is the biggest cost. That's why we make them! To use a bit of time with skills our grandfathers used.
K2
 
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Hi Sprocket, here are some I have... may inspire you?
P8062449.JPG

Top: The bought (Black) bender needed the flat steel strip changing to a stiffer aluminium bock to work successfully.
Bender with a bench screw: A "Junero" 3mm tube "scroll tool": Juneero Patent Scroll Tool
The silvery bender towards the right is just a proprietary brake pipe bender. My favourite. Tools and wheels are roll benders - home made.
K2
 

sutty

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Sprocket, not used to working in miniature, the theory is basically the same just smaller scale.
Steamchick explained about superheaters to me and suggested routing it down the flue to the burner and back again, the bore of the flue is 22.2mm so i had to get a tight bend, the form roller is 16mm dia and the rad is 3mm for the 6mm x 1mm tube, the side stop and slide block is 10mm square with a 3mm rad groove milled along the length, there is a slight flattening on the bends but when i make the propper job i have some really fine silver sand to pack the bore with. here's some pix.
best regards sutty
 

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sutty

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Hello guys , my apprentice is still on holiday so no actual work done, I've redesigned my boiler and had a think about the burner and tank. I've also had a go at pressing out the boiler end caps. The 3mm copper plate still hasn't arrived yet so I used a bit of 3mm aluminium just as a test piece, it worked ok and fitted well.
we're going to make a chicken feeder type of tank and a semi vaporising burner, have a look at it and feel free to pull it apart if you see any errors,

Regards Sutty
 

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Hi Sutty, I sometimes think we are all apprentices in this together?
As you know, I think you have solved the design of the boiler sensibly.
As I have not made this type of burner - but understand the principles - I can only suggest you need to allow a way for the air to get beneath the burner itself, in order to pass up the centre tube. You need a space at least 1/4 as wide as the diameter of the centre tube. A 1 inch tube needs 1/4 in clearance beneath the burner. OK?
On the Chicken feeder tank, I know my name is Chicken, and I like to be fed, but this is a new one on me!
Hope it works!
K2
 

sutty

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Cheers Ken, I was going to draw some little feet on the tank and burner but got side tracked. I put the valve on the feed pipe so we could swap burners.
I drew the feed tank up like that so there was no open fuel except in the burner it self, I'm still trying to think up a way of making the feed pipe between the top half of the tank and bottom half adjustable so that the level in the burner can be altered.
Another question for you Ken, can you use Silicon bronze rods on the boiler ? I've got a Kilo of 1.6 BOC rods.
We're making the tank first so we'll be able to see if it works like we want.

Best regards sutty
 
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