Kozo A3 3/4 scale up and running sort of

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GregE
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Re: Kozo A3 3/4 scale up and running sort of

Post by GregE »

Thanks folks! I think the A3 is about a perfectly proportioned locomotive for its era, and I like the tank engine A3a even better. Al, I did the design changes myself - 'kit bashed Kozo' as a friend says- working from photos and drawings in a locomotive cyclopedia. Credit to Dave Sclavi for recommending the Scalecoat paint he used on his PRR loco- it's still looking good after 6 years of running.
It's a well balanced design technically in my opinion, and running it isn't hard if you're used to small firebox locos and have appropriate fuel. Trouble shooting your water supply can improve performance. It's small enough that it isn't forgiving of leaking checks or poorly performing pumps. It was a revelation to fire with Welsh coal versus the generic eastern coal I started with! Now I mostly use a fast burning western US with success. It likes to keep moving and have a load for stronger draft. Timid lallygagging can lead to a tepid fire and low water.
On this lap in the video I think it was just me, usually I have a flat car with a cinder block or a passenger.
Greg Easter
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Bill Shields
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Re: Kozo A3 3/4 scale up and running sort of

Post by Bill Shields »

Ah...another track with usable 2.5" gauge!
Too many things going on to bother listing them.
GregE
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Joined: Mon Jan 19, 2009 10:53 pm
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Re: Kozo A3 3/4 scale up and running sort of

Post by GregE »

Yes! We would love to have the 2.5" get used. There was a loco in the club- maybe a northern - but it is down with boiler woes and hasn't been seen for 10 years. We have 5" too for the European adjacent! ;)
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Bill Shields
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Re: Kozo A3 3/4 scale up and running sort of

Post by Bill Shields »

Maybe j need to visit that part of the usa when I have time with 3 gauges of locos all packed in my Subaru
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sky
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Re: Kozo A3 3/4 scale up and running sort of

Post by sky »

Hi Bill,
I have been working on other issues and am now back to the axle pump. Where do I find a design for a hand pump that pushes through the axel pump?
sky
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Bill Shields
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Re: Kozo A3 3/4 scale up and running sort of

Post by Bill Shields »

It is not the pump but the piping
Too many things going on to bother listing them.
sky
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Re: Kozo A3 3/4 scale up and running sort of

Post by sky »

any hint on how modify Kozo's design to get it to do that? Kozo has the axle pump feed the boiler on the left and the hand pump on the right.
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Builder01
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Re: Kozo A3 3/4 scale up and running sort of

Post by Builder01 »

Pipe it so the output of the hand pump goes into the input of the axle pump (instead of into the boiler). The output of the axle pump would be left as is. This will allow you to blank off the boiler bushing that would normally come from the hand pump. (Use it for an injector or steam pump!) To use the hand pump, you will have to remember to close the axle pump by-pass valve.

As Bill said, it's the piping, not the pump design.
sky
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Re: Kozo A3 3/4 scale up and running sort of

Post by sky »

Thank you for the help. Much appreciated. Will have to look up what an injector and steam pump are.
sky
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Builder01
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Re: Kozo A3 3/4 scale up and running sort of

Post by Builder01 »

sky wrote: Fri Sep 03, 2021 1:56 pm Thank you for the help. Much appreciated. Will have to look up what an injector and steam pump are.
sky
An injector and steam pump are devices to put water into your boiler. The steam pump, is actually a steam driven water pump. An injector uses boiler pressure steam to put water into the boiler. Both are very different sorts of devices but very handy, much easier to use than a hand pump to top off your boiler when the loco is standing still or, on the go.
piedmontg
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Re: Kozo A3 3/4 scale up and running sort of

Post by piedmontg »

Here is a example of feed water system using hand pump / axle pump / and bypass through the axle pump, swiped from a book someplace do not know where. Lots of plumbing. Also useful for clearing stuck checks or air lock in the axle pump.
Locomotive Boiler Feed.jpg
sky
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Re: Kozo A3 3/4 scale up and running sort of

Post by sky »

Thank you. I have seen this, which prompted the question of an alternate pump design. This pump looks like a double pump, feeding the axle pump and used as an axle pump. sky
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