Need Juliet Help

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Bob D.
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Joined: Thu Jun 21, 2012 10:43 pm
Location: Saco, ME. USA

Re: Need Juliet Help

Post by Bob D. »

Bill,
I have a very nice running Juliet II with Baker gear. If there are any direct measurements I can make to assist you I will. I didn't build it and have no plans. With the 1" cylinders it pulls really well and is a great little steamer.

Bob D.
3/4" Juliet II 0-4-0
3/4" Purinton Mogul "Pogo"
3/4" Hall Class 10 wheeler
3/4" Evans Caribou/Buffalo 2-8-0
3/4" Sweet Violet 0-4-0
3/4" Hunslet 4-6-0
3/4" Kozo A3. Delayed construction project

1 1/2" A5 Camelback 0-4-0
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Bill Shields
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Re: Need Juliet Help

Post by Bill Shields »

thanks for the offer

what I need is the diameter of the circle described by the return crank.

if you don't have plans, it is difficult to determine without putting the wheel set up in a mill or lathe and taking direct measurements.
Too many things going on to bother listing them.
Bob D.
Posts: 381
Joined: Thu Jun 21, 2012 10:43 pm
Location: Saco, ME. USA

Re: Need Juliet Help

Post by Bob D. »

I would think that that described circle is ultimately determined by radial postion the eccentric crank is set to with the valve gear assembled and the valve port postion known. Having the crank clamp on for intial timing and pinning when it is proven right seems prudent. Not sure this crank circle can be determined real world correct before hand. Making the distance of the pin centers of the eccentric crank to print gives the described circle if the crank is orientated properly.
I've been thru Baker setup on 3 locos and never knew what this described circle was beforehand....it is what it is when the timing is correct.
That or I just misunderstand you.

Bob
3/4" Juliet II 0-4-0
3/4" Purinton Mogul "Pogo"
3/4" Hall Class 10 wheeler
3/4" Evans Caribou/Buffalo 2-8-0
3/4" Sweet Violet 0-4-0
3/4" Hunslet 4-6-0
3/4" Kozo A3. Delayed construction project

1 1/2" A5 Camelback 0-4-0
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Bill Shields
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Location: 39.367, -75.765
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Re: Need Juliet Help

Post by Bill Shields »

you understood me correctly.

the designed travel of the valve (which I do not know) is ultimately determined by the diameter of the return crank circle and the length of the crank.

I know the length.

since the valve gear has so much slop in it, it is very difficult to think that I can get the position correct at this point without knowing what the circle should be.
Too many things going on to bother listing them.
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Bill Shields
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Re: Need Juliet Help

Post by Bill Shields »

it I had a half a brain

since the return crank should be 90 degrees ahead of the main crank pin, then if;

crank pin throw is .75 (from drawing)
return crank length is 1.0 (from drawing)
to put the return crank pin 90 degrees to the axle center would work out .621 inches (close enough to 5/8).

This assumes that the baker connecting rod is 'centered' at the same elevation as the axle center...so if the eccentric rod has any inclination, then I will have to account for that difference...

all things considered...a 1-1/4 return crank circle diameter is probably close enough for this loco.

My guess is that at the time the drawings were done, LBSC didn't feel it was necessary to dimension the circle since 'everyone knows how to calculate THAT'!

oh well....guess I am not as smart as a 5th grader in 1925
Too many things going on to bother listing them.
SteveM
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Re: Need Juliet Help

Post by SteveM »

Bill Shields wrote:oh well....guess I am not as smart as a 5th grader in 1925
There's a lot of that going around.

Steve
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Bill Shields
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Re: Need Juliet Help

Post by Bill Shields »

My guess on crank circle (5/8") couldn't have been too bad.

Juliet's made it around the track for better part of 3 hours yesterday before one crank 'slipped'.

Now if we can just get the suspension to clear the frogs and guard rails on the turnouts.....another story of 'take it apart and make it correct instead of making it correct to begin with.'
Too many things going on to bother listing them.
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