Author Topic: Help needed on 4-4-0 Baldwin  (Read 769 times)

Offline Grant Jones

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Help needed on 4-4-0 Baldwin
« on: August 07, 2018, 05:24:11 PM »
I am constructing a 4-4-0 Baldwin, 1872 vintage. Drawings are not available for the model I am building, however I have a couple of plans that are very close. The one big difference with my model is, it has three domes...the one closest the cab being the steam dome, the middle the sand dome, and the front one closest to the smoke box contains the throttle. The throttle valve is the slide valve type. Can someone provide me with the sketch or drawing of the general arrangement that would illustrate how I pipe the steam line from the steam dome to the throttle dome. I am building in 1" scale.

Offline Dan Rowe

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Re: Help needed on 4-4-0 Baldwin
« Reply #1 on: August 07, 2018, 05:55:59 PM »
Grant, attached is a drawing sectional drawing of a 1871 Baldwin 4-4-0 with 3 domes, the forward dome is simply another steam dome. The throttle gets steam from the forward dome and sends it through the forward tube sheet to the cylinders.

It looks like the rear steam dome is simply a fancy mount for the safety valve and whistle.

Dan
ShaylocoDan

Offline crueby

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Re: Help needed on 4-4-0 Baldwin
« Reply #2 on: August 07, 2018, 06:00:25 PM »
Hi Dan,


What are those two fittings coming up above the firebox into the rear steam dome? Blower intakes? Gauge pickups?


Chris

Offline Dan Rowe

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Re: Help needed on 4-4-0 Baldwin
« Reply #3 on: August 07, 2018, 06:07:54 PM »
Chris, I think that they are stay rods riveted to the dome shell.

Dan
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Offline Grant Jones

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Re: Help needed on 4-4-0 Baldwin
« Reply #4 on: August 08, 2018, 04:07:52 PM »
Thanks Dan that section you posted really clarifies what I needed to know.

Offline kvom

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Re: Help needed on 4-4-0 Baldwin
« Reply #5 on: August 09, 2018, 11:50:55 AM »
You could always move the throttle to the dome closest to the cab if that makes it easier.

Offline Grant Jones

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Re: Help needed on 4-4-0 Baldwin
« Reply #6 on: August 09, 2018, 09:52:10 PM »
I guess I could move the throttle to the other dome, and no one would ever know, in fact, if I did this, the steam discharge line, running longer thru the boiler would likely give me more superheat. The only real saving would be in the length of the throttle rod. I am trying to do as exact a build as possible to the original, which means I will be putting the three domes on, so I will do it as that old drawing shows. Thanks kvom.

Offline Grant Jones

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Re: Help needed on 4-4-0 Baldwin
« Reply #7 on: December 06, 2018, 08:26:28 PM »
As I progress with my build, an elderly guy who has since passed on told me "make sure the driving wheel centre is on a straight line with the cylinder centre line.
I sourced cylinder castings that look like this will not be possible, with the result being the wheel centre line will be about 1/2" lower than the centre line of the cylinders.
It appears that the driving link length will be different, but I cannot see any other reason for concern. Can anyone tell me more about this.

Offline crueby

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Re: Help needed on 4-4-0 Baldwin
« Reply #8 on: December 06, 2018, 09:12:03 PM »
It seems to me that if the center of the cylinder is not in line with the axle, you will wind up with a slight speedup on one half of the stroke compared to the other, which would conflict with the other sides motion, and make the overall turn jerky? I looked at a plan book I have for a narrow gauge Baldwin, and the centers are all in a line.

Offline Stuart

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Re: Help needed on 4-4-0 Baldwin
« Reply #9 on: December 07, 2018, 09:33:07 AM »
Grant

Are you sure he did not mean the axle must be at right angles to the center line of the cylinders when looked at from above or below the frames/chassis

There are a lot of loco’s that the cylinder is inclined in the horizontal plane when viewed from the side

Think about it the cylinder and cross head guides are fixed to the frame but the wheel will articulate with the suspension so it can not be always in line

Think about Stevenson’s rocket loco that has them inclined to the extreme but it worked fine


One tip do not make the axle blocks to good a fit in the horns they need some slop else the axle will bind up

Stuart
My aim is for a accurate part with a good finish

Offline Grant Jones

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Re: Help needed on 4-4-0 Baldwin
« Reply #10 on: December 08, 2018, 03:28:00 PM »
Thanks Stuart for your reply. With the drivers “sprung” I have to think that when the loco is finished the weight distribution will bring this into line.