The Unofficial Mamod and Other Steam Forum

mogogear · Posted: Tue Nov 03, 2009 6:47 pm Post subject:

Great sketch to boot!
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Lagniappe readily offered and accepted,

Mo

This week I are His Most Noble Lord Mo, the Apocalyptic of Old Tonbridge Wafers

Caprice · Posted: Tue Nov 03, 2009 8:40 pm Post subject:

STEAMPROPULSION, thanks

, I'm feel kind of honored, Shall be interesting... I will try to help out if there's any problem when you build it...not that I'm any expert though.

I have also a boiler with a clean center flu(no cross tubes). Soldered two 4mm tubes across the opening in the bottom. Seems to absorb a little more heat from the fire..or if it's my imagination?
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Thanks, mogogear.

STEAMPROPULSION · Posted: Wed Nov 04, 2009 7:19 am Post subject:

THIS TYPE OF BOILER IS THE LEAST EFFICIENT AMONGS THE VERTICAL ONES. AN IMPROVEMENT WOULD HAVE BEEN A SERIES OF SLIGHTLY INCLINED CROSS TUBES SOLDERED THROUGH THE CIMNEY.
BUT THIS MODIFICATION CAN BE CARRIED OUT ONLY FROM THE BEGINNING OF THE CONSTRUCTION.
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GIOVANNI
SKIPE name: ark.gsorrentino

Caprice · Posted: Wed Nov 04, 2009 9:04 am Post subject:

You are right, that's a more efficient way after what (little) I understand. I think though that you can modify a boiler that way, even after it's finished, but it's more work of course. I didn't want do go that far, so I did a "quick fix":

(It doesn't show in the picture but the tubes are a little inclined "horizontally".)

I should have taken some measurements how long it takes to boil water before/after modification. Now I can only guess if it improved the time...I think so though.

logoman · Posted: Wed Nov 04, 2009 2:29 pm Post subject:

My small Hemmens has the same problem, the burner flame forming a point up through the chimney. I heard a tip (havent tried it) that some wire from the heating element of a hair drier, formed into a ball and lodged in the chimney would convect more energy to the water.

STEAMPROPULSION · Posted: Wed Nov 04, 2009 2:44 pm Post subject:

Miles,
I was thinking about placing over the flame one of those heat diffusing round elements (steel crossed net) used on gas stoves.
I don't know if we are talking about the same thing: maybe italian hair driers are different...
Cheers.
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GIOVANNI
SKIPE name: ark.gsorrentino

logoman · Posted: Wed Nov 04, 2009 2:59 pm Post subject:

STEAMPROPULSION · Posted: Wed Nov 04, 2009 3:03 pm Post subject:

TO CAPRICE:
I EXAMINED THE PICTURE OF YOUR MODIFIED BOILER.
THIS IS WHAT I THINK:
I THINK THAT YOU HAVE ADDED A BIT MORE OF HEATING SURFACE TO YOUR BOILER, BUT YOU HAVE NOT INCREASED WATER CIRCULATION SPEED UNLESS YOUR TWO TUBES ARE ASYMMETRIC.
(SEE SKETCH).
TO INCREASE EFFICIENCY, WATER TUBES MUST BE PLACED AT DIFFERENT LEVELS.

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GIOVANNI
SKIPE name: ark.gsorrentino

Caprice · Posted: Wed Nov 04, 2009 9:06 pm Post subject:

STEAMPROPULSION, the ends are at different levels but maybe not as much as in your picture, ~1-1.5cm and not asymmetric I'm afraid. I'm happy with it though even if it probably could be better.

Here's a video of it working(~15psi)with this threads burner(Posted also in the "More Whistle" thread):

(Warning, four minutes of whistle blowing.)

mogogear · Posted: Wed Nov 04, 2009 9:27 pm Post subject:

logoman · Posted: Thu Nov 05, 2009 9:15 am Post subject:

Thanks Greg, that's a good idea and will save me experimenting with burners.

Giovanni, could you show me how far into a Stuart Babcock boiler the tubes go?

STEAMPROPULSION · Posted: Thu Nov 05, 2009 12:04 pm Post subject:

Miles,
this is something you should not have asked to me!
I have already packed all the steam books and documents I had in my office in four huge boxes.
As you know I'm moving from my office and this has been the first sacrifice.
In these boxes there an original STUART "blueprint" of the Babcock boiler, coming directly from Stuart Technical department.
I don't know if I can retrive it anymore.
My sketch follows exactly A. Raymond's layout of his famous boiler intended to be coupled with a STUART BB HIGH SPEED engine.
The ends of the water tubes must be at different levels working as a syphon.
But don't loose your hopes.
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GIOVANNI
SKIPE name: ark.gsorrentino

STEAMPROPULSION · Posted: Thu Nov 05, 2009 12:19 pm Post subject:

CAPRICE,
I think that you must be satisfied with your boiler output, which seems to be more than adequate for a whistle.
How does it go with a steam engine?
This reminds of the chapter of a french steam book named: "Le secret c'est la temperature"
This means that one of the most important factores involved in the production of steam is the FIRE.
I HAVE SERIOUS GAS TANK FREEZING PROBLEMS ON MY ANTON PLANT.
THIS IS A CHALLENGE FOR STARTING A NEW SERIOUS THREAD ON THIS TOPIC:

"GAS TANK CHILLING PROBLEMS: HOW I GOT RID OF IT"
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GIOVANNI
SKIPE name: ark.gsorrentino

Caprice · Posted: Thu Nov 05, 2009 2:10 pm Post subject:

Thanks STEAM PROPULSION!

It can drive a VR1A(Graham Industries) OK I think, but that engine probably need a bigger boiler. It's the only one I have at the moment though, just started with steam, so I have nothing to compared to.

STEAMPROPULSION · Posted: Thu Nov 05, 2009 2:13 pm Post subject:

GREAT DRAWING.
THAT'S WHAT I MEANT.
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GIOVANNI
SKIPE name: ark.gsorrentino