Hi Geoff,
Of course, they were pieces of eight. Just using a little poetic
licence relative to the correct lapping method you described.
Question:- If I start getting 1/8 size red hot coals being thrown out
of the chimney, of the Duchess, does this mean the blower draught is a
little
Tony,
Any discussion of coal, blowers and exhaust nozzles is always worth
discussion. Firstly, I would hazard a guess that cinders (in pieces of
eight?) from the chimney would be more likely be a problem with the
smaller scales. You write blower, do you mean the exhaust nozzle too, or
just the
The screening on a full size locomotive was not below the petticoat. That
is just a bad place for it and would hinder draft way too much. In the
smoke box there are screens and baffles that catch the cinders which gives
more surface area for the screening. Check the Locomotive Dictionary for a
Hi Geoff,
Yes, you are correct. I did mean the exhaust nozzles. They both have in
fact already been reduced once by Mike, to reduce the fierceness of the
blast, which had caused the previous high temps, and blistered paint!. This
weekend, with the red coals flying, the casing temperature was
Hi JR,
I agree, I did not really want to have to put a screen inside the
petticoat, unless a last resort, and already feared it may affect the path
of the nozzle blast. So I just will have to back off on the blower a
little, and just enjoy the sparks as opposed to the 1/8+ size cinders.
Perhaps these are the screens you refer too?. I have thought
of trying a temporary fireplate to my 10mm coal engines though.
Regards,
Tony D.
Tony,
The screens J.R is refering to are located in the smoke box, and right
in front of the tube sheet. It is a heavy coarse wire cloth,
Tony,
Interesting, JR May had some very good comments, J R?? is that James
Robert, John Richard, Jack Roger or what??
Anyway, a friend and I often thought of a control valve to modulate the
amount of steam that is admitted to the exhaust nozzle from the cyls, just
as the blower can be
Interesting... I thought I had read that you should increase the nozzle
size to decrease the blast? Larger nozzle means slower jet speed and
therefore less draught, not to mention less restriction on the exhaust
taking up power.
Guys? What's up with that?
Trot, the somewhat confused,
Trot Fox,
A nozzle orifice can be too small or it can be too large! If it's too small
there may be the velocity to create some pressure drop in the smoke box
but not enought volume to be effective. Example, a 1mm orifice in a 1
scale loco wouldn't work very well!! The nozzle has to be just
