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    • January 20, 2019 11:03 AM EST
    • Does anyone know the status of Pacific Western G?  Their website  appears to be no longer active.  

       

      I had purchased one of their structures and am thinking of adding another one or two.

       

      Thank you for any information you can provide.

    • January 19, 2019 8:49 PM EST
    • I actually new that one. But didnt know what you were asking because I didn't know the locomotive. 

    • January 19, 2019 12:43 PM EST
    • " Rooster " said:

      Now if someone can explain to "me" how Utility's drivers were not quartered I would understand better myself

      I believe they were quartered from left side to right side. Actually, quartering refers to the wheel pin position, for the drive rods, on one side of the locomotive relative to the other side.

      Due to the way the front drivers and the rear driver, on each side, are linked together, they too are "timed" and will always rotate in the same positions relative to each other.

      I think

       

      Adam

    • January 19, 2019 10:43 AM EST
    • " Rooster " said:
      Devon Sinsley said:

      Gary,

       

      That really helped me understand it

      Now if someone can explain to "me" how Utility's drivers were not quartered I would understand better myself

      That is a somewhat obscure question.  Who's 'Utility' - do I have to go back 4 pages to figure it out?  Why were the drivers not quartered?  And why is "me" in quotes?

    • January 18, 2019 7:55 PM EST
    • Devon Sinsley said:

      Gary,

       

      That really helped me understand it

      Now if someone can explain to "me" how Utility's drivers were not quartered I would understand better myself

    • January 18, 2019 7:47 PM EST
    • Gary,

       

      That really helped me understand it

    • January 18, 2019 5:57 PM EST
    • If you visit the Baltimore & Ohio RR Museum in Baltimore, you can climb all over Old #1, a 4-6-0, and move the reversing lever.  You can then go around the side and have someone else move it so you can see what it does.

    • January 18, 2019 2:16 PM EST
    • David,

      Even more difficult in a 1/8th scale steam engine :). Many in the ride-on hobby have changed this valve gear on ten wheelers from Stephenson to Baker gear. In Baker valve gear, everything is done with linkage and links. No cams involved.

       

      I have a few more photos of my old engine (I sold this engine back in January 2017 to a corporate executive pilot). He says he will have it under steam in about three months. These photos make it a little clearer on what actually "moves" to make the engine run in forward or reverse.

      This view shows the three drivers on the engineer side of my steamer. Note the main rod and crank. This is the center of all the Stephenson valve gear. The eccentric cams are attached to this axle. If you look between the main center driver and the front driver, you can see where the rod for the reverse quadrant is attached. When you throw the quadrant handle forward in the cab, it moves the lifting link and this moves the eccentric links (the crescent shaped links with the precise slot where the die blocks are located) up and down.

       

      This photo shows a little more detail of the reverse rod link and the lifting link inside the frame. The small link between the reverse link and the front driver is the link that moves the valve stem and slide valve (in this engine) or a piston valve in the steam chest above the cylinder block.

       

      I hope thjis shows a little more detail of the reverse link, lifting link and the eccentric links in the background inside the frame between the drivers. The main rod has been removed.

       

      A much better photo of the valve gear components between the drivers and all inside the frame. Pretty complicated mechanism in its. State of the art for steam engines from the 1830's right up to the early 1900's. Just very difficult to maintain.

    • January 18, 2019 6:37 AM EST
    • Just oiling the links and such during a routine water stop was difficult.

    • January 17, 2019 8:51 PM EST
    • Devon and all,

      I took this photo of my 1/8th scale, 1-1/2 inch per foot, Gene Allen ten-wheeler a few years ago. I had just finished some design changes to the eccentric rods going from the eccentric cams on the main axle to the eccentric link. You can see the four "cams" (mounted on the axle, 2 left and 2 right). The eccentric "cam straps" wrap around the cams causing the "wobble motion" Devon talked about. The extreme left hand cam and strap is the "forward strap" for the left hand cylinder and piston. The strap next to this is the "reverse strap" for the left hand cylinder and piston. On the extreme right is the "forward strap" for the right side cylinder and piston. The strap immediately to it's left id the "reverse strap" for the right side cylinder and piston. Just forward of the cams and straps, you can see the four eccentric rods that attach to the valve gear "links". One link for each cylinder. There is a "die block" which slides in a precisely machine arc in each link. the position of the die block in the slot in the link provides the amount of motion that the slide valve or piston makes inside the steam chest above the cylinder block and pistons. As you can see, when the boiler is in place over all this mechanism, it is extremely difficult to access for adjustment and maintenance. This is the main reason that Stephenson valve gear was eventually replaced by other valve gear mounted on the outside of the frame.

    • January 19, 2019 4:00 PM EST
    • *entered in error

       

    • January 18, 2019 5:45 PM EST
    • Actually, the 'haystack' firebox had less to do with heat location and more to do with metallurgy and making as few holes in the boiler's plates as possible.

       EDIT, also termed Haycock firebox.

      Read this if you can buy or borrow a copy, very much worth it.

      [img]https://farm5.staticflickr.com/4409/35956485320_f37ff096bb_z.jpg[/img]

    • January 17, 2019 7:01 PM EST
    • Mick Benton said:

      This might provide some idea

      https://himedo.net/TheHopkinThomasProject/TimeLine/IndustrialRevAmerica/SteamEngines/JohnWhite.htm

      That looks like a great read. Will need to dig into that.

       

    • January 17, 2019 7:00 PM EST
    • Randy Lehrian Jr. said:

      I agree with David that the hottest area is going to be around and above the firebox, but I believe that most steam domes were in the middle of their boilers for a different reason.  The reason would be so that when a loco would travel up or down a grade the water would not try to pile up at either end of the boiler and then get sucked up in the steam pipe causing hydro lock in the pistons.   With the dome centered the water will just rush past underneath to which ever end of the boiler is lower.  If the steam needed to be more hot or dry, then a super heater was employed.  This would be where the steam pipe would be routed though a fire tube/flue there by heating and drying it further while it traveled through.  Looking forward to your first live steam build Devon!

      That is exactly what I was thinking when I saw this design. I agree with David as well that it was likely experimental and didn't work well and that is why we didn't see it used. My guess was the thought process was to put the steam dome where the heat would be greatest and that would be above the fire box. And this was likely before they realized the idea of a super heater. But as you mention on an up hill this design would prove to be pretty ugly for the very reason you mention.

       

      As for my first live steam. I actually have little more than a passing interest in it. I am not saying never, but not anytime soon 

    • January 17, 2019 6:52 PM EST
    • This might provide some idea

      https://himedo.net/TheHopkinThomasProject/TimeLine/IndustrialRevAmerica/SteamEngines/JohnWhite.htm

    • January 17, 2019 6:50 PM EST
    • I agree with David that the hottest area is going to be around and above the firebox, but I believe that most steam domes were in the middle of their boilers for a different reason.  The reason would be so that when a loco would travel up or down a grade the water would not try to pile up at either end of the boiler and then get sucked up in the steam pipe causing hydro lock in the pistons.   With the dome centered the water will just rush past underneath to which ever end of the boiler is lower.  If the steam needed to be more hot or dry, then a super heater was employed.  This would be where the steam pipe would be routed though a fire tube/flue there by heating and drying it further while it traveled through.  Looking forward to your first live steam build Devon!

    • January 18, 2019 6:42 AM EST
    • Gee, my license says "Doubles and triples" but it doesn't mention quadruples.

    • January 17, 2019 9:31 PM EST
    • That IS what it says on the front bumper, DOH!

    • January 17, 2019 7:50 PM EST
    • Don't they call them 'Road Trains'?