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[rfurzer]

I am experimenting with boiler firing before finalizing my boiler design.
I have a $10 Chinese camping stove and $4 adapter from eb.

The stove is actually rather nice with a brass body, flexible pipe, needle valve and folding legs.
The round burner unscrews from the mixing tube- it has an odd thread, 10.7mm dia- presumably truncated 7/17 and 24 tpi- not the UNEF 28.

The rated performance is 3500w but I have yet to do a fuel consumption test.

The jet- I've not measured it yet either- is undersized for the valve- max flame size at about 75% open. The flame is very nicely adjustable.

The adapter allows use of the really cheap butane cylinders rather than the more exxy screw on camping bottles. It is not a superbly secure device- can be wrung off the can without releasing the mechanism. A screw bottle would be much better.

Note for the uninitiated, the cheap bottles have an internal feed tube that delivers liquid butane unless the can is upright on its base or on the side with the notch in the rim upwards. The burner spectacularly flares if the can tips - doesn't happen with screw bottles.

The plan is to modify the mixing tube to make a poker burner. I will post progress.

[rfurzer]

Argh- so hard to load pics. The computer keeps saying no!

[rfurzer]

And some more

[rfurzer]

Note the notch- at 9o'clock

[rfurzer]

Either can on the side with notch UP or can upright or else....

Ps for the eagle-eyed the can is back upright- I tipped it for the flare and the stood it back up.

[rfurzer]

Nice brass fittings

[rfurzer]

And please forgive "7/17" thread in the first post- a typo not a tasmanian oddity. Obv 7/16!

Also not sure why the pics look squished

[Jerry C]

Yeh, noticed one of my pics appeared squished yesterday. Ok when pic opened though.
Jerry.

[Martin (Admin)]

 
( try http://cubeupload.com/ )

[rfurzer]

The jet is 0.45mm, bigger than I expected.

Fuel consumption 20g in 6 min = 200g per hour. I make that 2.75 kW.

[southsteyne2]

You can buy little camping stoves in Aus for less than 20 dollars and 4 pack butane $4.40 just wondering why the can does not flair as the are horizontal in the stove?
John

[rfurzer]

G'day john,

Those camp fires take the can on its side but with the notch up. If you went so far as to tilt the whole thing- flare. The flexible tube with adapter does not prevent the unsafe can orientation in the same way those Bunnings/ gasmate ones do.

Btw I much admire your manly ferry. I have a future plan for a 'barrenjoey'/north head model- remember her in diesel NH guise as a schoolboy, but want to build a steamer. Where did you find the hull drawings? The Baragoola website shows a schematic with a weird plate- like keel for nearly half the draught at midsection.


Russ

[southsteyne2]

Thanks Russ the south steyne is completely scratch built as I could not find plans for it so I took numerous photos of her in Darling harbour and worked out the hull shape using corel draw as only needed one half being double ended scale at 1/4inch to foot
Cheers
John

[rfurzer]

Here's the schematic of baragoola

[rfurzer]

And a link to s.s (is that you too, john?)
http://www.ferriesofsydney.com/index.php?topic=1489.25

[southsteyne2]

Great link Russ very interesting info you may notice the lines on the S Steyne are quit different  to the north head and dee why having no  straight lines making the south steyne a very difficult model to build especially the numerous windows most with a slant forward or to the stern,many people who have seen the model have commented on the memories she brings back also some that worked on her so she is always a good talking point
John

[rfurzer]

I have been experimenting with my burner.
I had a 1/2 inch bit of K+S brass tube, made 20 slits halfway 1/4" apart with a junior hacksaw.
Made up a plug for the far end and bored out the stove body to take the tube as a push fit.

Results- burns nicely with no blow back at about half max flow. The far end blows out at full flow.

If turned upside down will burn nicely flat out.

I had a bit of 29mm tube as a mock- up furnace flue but the flame won't go inside the flue.

Back to the drawing board!

[rfurzer]

1 overview
2 half open gas valve- good flame attachment
3 fully open - flame blown away from the slits at right
4 upside down. Fully open

[Synthpunk]

Ooh! Thats pretty neat! Have you tried putting some fine metal gauze in the tube? All rolled up like? I will have an experiment with my monotube boiler burners, they look fairly similar. I got the ones that go on the resealable canisters, they seem pretty robust. Any further progress to report with your burner? ;c)
All the best,
Rich

[rfurzer]

I haven't tried gauze. These would go well with the Victoria Flash Plant, your design of which I watch with interest and envy.
What they don't do is work up a flue- I plan to make a scotch type boiler. The same jet assembly makes a nice blow lamp, which I am fettling presently.

[southsteyne2]

Hi everyone after much playing around with all sorts of designs with none working that well so I opted for the fire tube burner from clevedon steam ,this burner will produce 20 psi in approx 4 minutes for 4 in x 8 in boiler and have had no problems over 4 years not cheap but worth every cent
cheers
John

[Synthpunk]

That does look like a very nice burner!
I have a few water tube boilers that im probably going to just buy burners for when i get round to sorting them out. Unfortunately they are mostly odd flue sizes. I was going to get them made by maccsteam, as he does custom sizes and very reasonably priced.
I have a K N Harris style scotch return boiler that is nothing short of amazing, but i have no idea what to fire it with. I have a suspicion it might have been built for coal! The flue is very large, and rivetted around the inside lip, so a push on gas burner wont fit.


That and the fact that it holds several litres and was designed with a 120 psi working pressure means its going to be a pain to fire, never mind get tested and certified, i can tell... Its all flanged connectors, very attractive, but a pain to dismantle and blank off for hydrostatic testing.


My attentions have now turned to flash boilers, with a totally different layout to standard boilers, so a standard boiler burner isnt going to work as well. Hence my excitement about russ's experiments- gotta love the interwebz. Allowing geographically distant strangers to geek out about obscure technical details since 1993. Hooray! :)


Cheers!


All the best
Rich

[rfurzer]

Finally! Some tinkering time.
I have made a fire tube mockup with bits from the scrap bin- specifically a 29mm furnace and 19mm return flues with a sheet metal combustion chamber. The idea is to see if the burner works up a tube. I had imagined 3/8 or 1/2 return flues (more of them) and a 32mm furnace ( biggest easily used in the AMBSC rules).

The burner is a 1/2 brass tube going into a 1" bit with a drilled nozzle .

It looks a beaut but there is a bit of flame at the end of the flues no matter what I do with primary and secondary air.

I conclude that it isn't possible to use a 0.45mm jet (no16??) up a 29 mm tube.

Plan b will be 2x 25mm flues and smaller burners

[Synthpunk]

I've now got my take on your idea for a poker burner working in an enclosed flue. The trick is to balance the flow of gas with the flow of air into the combustion inlets on the burner tube with the surface area of the jet holes in the burner tube, along with the gauge of stainless mesh inside the tube. And the shape and dispersion characteristics of the 'disturbulators' I came up with that go in the burner tube to mix it all up properly and help regulate gas flow. Basically, I'd bet that you don't have enough burner hole surface area for the O2 and gas flow provided, and the gas flow in the burner tube isn't mixed enough. That's what I've worked out at any rate. I've now got my latest burner design kicking out a phenomenal amount of heat in an enclosed flue ( the burner space of my new, fully enclosed, kinda sorta terrifying mark 3 flash boiler.) The amount of heat available is actually scary, it's such a step up from before. It now sucks all it's combustion oxygen in through the inlet holes on the burner pipe without blowing it's own flame out, which again, I'll bet is actually what was happening before. I'll post a pic. Once you get a handle of the gas flows and what's balancing what it should all make sense.

Cheers!

Rich.

[Synthpunk]

Btw when I say ' balance the flow of gas' etc I don't mean manually turn it up and down. The holes simply have to be the right size to begin with. Again, I'll send you a picture.