Union Pacific Big Boy 4012 in 1.5"

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DanSmo
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Location: Melbourne, Australia

Re: Union Pacific Big Boy 4012 in 1.5"

Post by DanSmo » Sat Jan 16, 2016 2:33 am

Somewhere in a book I have it states that Big Boys hauled one or two troop trains west over Sherman Hill during the peak of WWII. I'll try to find it again.

Kvom I think the rowdy passengers Benjamin Maggi was referring to were the non-scale kind haha.

Thanks Harlock. Tom Millers is one impressive machine, I've collected plenty of photos of it while I've been researching and that video of it on youtube is constant inspiration! What a privilege to have driven it, lucky man!

In other news I picked up my frames from the water jetters yesterday. I had them cut from 20mm hot rolled plate, 3/4" plate is non existent in Australia so I'm adapting the design to use metric size stock. I did look into having them Blanchard ground to size but I can't afford to spare any arms or legs. The Big Boy book by William Kratville is an incredible publication, so many detailed and unique photos that have never been published elsewhere. The picture shown of the one piece cast fames at GSC is a great visual reveal of what connects what bit to what. The mind boggles at the size of the furnace it must have taken to melt all that material, the number of cores, calculations, the cooling time and machines that performed the finishing work.
Attachments
2016-01-16 17.58.36s.jpg
Water jet cut frames
2016-01-16 18.18.31s.jpg
Cast Frames
I just don't understand pronouncing solder as "sodder"... where did the L go?

RET
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Location: Toronto, Canada

Re: Union Pacific Big Boy 4012 in 1.5"

Post by RET » Sat Jan 16, 2016 11:02 am

Hi,

Building a Big Boy is a VERY ambitious project, but your work is impressive to say the least. Don & I acquired our part built 3 1/2" gauge Big Boy in September of 2005 and it still isn't finished, but I'm working on it (you can see our record if you look up "Union Pacific Big Boy in 3 1/2" gauge" in the Live steam section of Chaski). Once in a while we post something on that thread to show our progress. I'm also working on other projects so updates don't happen too often. When you get to it, one of the things you should consider is the internal piping in the boiler for the turret connection. Without it, any hill you encounter is going to give you water, not steam in the turret.

If you don't already have it, the Union Pacific Historical Society sells a CD of the full size Big Boy drawings for both the engine and tender (all 2900 of them) for $35.00 US + postage. That is a real bargain. Believe me, when you want to make a part for Big Boy, there is no substitute for being able to pull up the drawing of the real thing to see how it was done!

As I've said in our Big Boy record, I would never start a project of this magnitude because I know I would never finish it. My hat's off to those who can.

Richard Trounce.
Last edited by RET on Sat Jan 16, 2016 3:38 pm, edited 1 time in total.

Mike Walsh
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Re: Union Pacific Big Boy 4012 in 1.5"

Post by Mike Walsh » Sat Jan 16, 2016 1:42 pm

RET wrote:Hi,

Building a Big Boy is a VERY ambitious project, but your work is impressive to say the least. Don & I acquired our part built 3 1/2" gauge Big Boy in 2006 and it still isn't finished, but I'm working on it (you can see our record if you look up "Union Pacific Big Boy in 3 1/2" gauge" in the Live steam section of Chaski). .
This is the one that was at CF right?

I passed up only because I didn't have a vehicle large enough to get it home. I still kick myself for not picking that up. Glad to see you've got it and are making progress.

Mike

RET
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Re: Union Pacific Big Boy 4012 in 1.5"

Post by RET » Sat Jan 16, 2016 3:36 pm

Hi Mike,

I don't know about Cabin Fever (I assume that's what CF means) but Don & I first saw the Big Boy in the spring of 2005 at Gunther Kundt's home in Sarnia where we had gone to see a 3 1/2" gauge Coventry Pacific that Gunther's father Gerhardt had also built. Needless to say, we were VERY impressed with the Big Boy! Gerhardt had died before he could complete work on it.

Don bought the Pacific, but we were told that the Big Boy had already been sold to Mike Albaitis of Michigan (another Mike!). We thought that was the end of the Big Boy story, but in September of 2005 Gunther called us and said that Mike Albaitis wanted to sell the Big boy and were we interested? It took us about ten minutes to decide that yes we were, so we told Gunther yes, but Mike had to bring it back across the border. We brought it home to my place and its been there ever since. If you want to see the long list of what we did to it, just look at the Chaski thread "Union Pacific Big Boy in 3/4" scale" in the Live Steam section. Work on Big Boy is slow because I have other projects, Dart, CNC mill, etc. on the go, but I would definitely like to see the locomotive run under its own steam.

From this you might be able to decide if ours is the one you are thinking of. It could very well be, because Big Boys aren't too common.

Richard Trounce.

Asteamhead
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Re: Union Pacific Big Boy 4012 in 1.5"

Post by Asteamhead » Sat Jan 16, 2016 6:47 pm

DanSmo wrote:Beginning to tackle the pilot truck, figured I'd start with the centring device. I had a local company CNC the ramps to ensure accuracy and the gears were done by wire EDM. All went together with no troubles. I'm getting about 3/8" of horizontal travel and 1/8" of lift either side of the centreline.

3/8" either side of centre doesn't seem like a lot of travel for a pilot truck, perhaps someone with experience can chime in?
Dan,

First to say you did an awesome job!
Maybe you didn't calculate the necessary side motion in favour of just using the prototype dimensions?
Look, there is a pretty simple method to calculate the needed side (lateral) motions of all axles depending on typical curvature (radius) of your RR.
First decide the optimal vertical center of motion of the total frame - maybe the center of the driver base for example.
Then multiply any (distance from that center) ² and devide this result by (2 x radius) of your typical curvature - all in the same dimensions [ mm ] f.e.
The final result will show the needed side motion or lateral motion (to either side!) of that particular point. This maybe an axle or the center of your boogie or else.
Four your 4000 projekt I did this for the given dimensions at scale 1.5 " and an estimated radius of 50 feet - about 15.000 mm or 15 m. In case your curvature at your RR layout is different, you can recalculate the results by yourself.
(1) Choosing drivers no. 1 and 4 beeing fixed in the frame will allow to just making flanges of drivers no. 2 and 3 smaller (by about 1/8 ") to negotiate that radius of 50 feet. Any added width of the standard gauge will help passing the curve!
But the 3 / 8 " lateral motion of your boogie won't pass that 50 feet radius, believe me.

(2) A different layout - drivers no. 1 , 2 and 3 lateraly fixed in the frame would help to reduce needed lateral movement of the boogie to just about 3 / 8 " - by the price of lateral motion of divers no.4!
Increased lateral movement of the connecting pin to the back frame when starting into a curve or leaving, is an issue too.

The vertical movement of 1 / 8 " at maximum lateral motion of just 3 / 8 " results in a lateral force of 1 / 3 of the (vertical) load on your boogie. General safety rules ask for a max. of 1 / 2 of the load on a wheel ( = 1/ 4 of the load on the boogie )to avoid derailments due to exess forces on the flanges.

Thus I recommend to increase the lateral motion to a minimum of 1 / 2 " to meet all the problems.
For my N&W A 1239 in scale 1 : 10 there are + / - 13 mm to negotiate (quite narrow!) 10 m radius.
A bit more than just 2 cents, sorry about that!

Looking forward to your progress

Asteamhead
Attachments
4000 in 1.5 scale _20160115 red.jpg
Lateral motion needed to run a 50 feet radius
A Rocker side motion red.jpg
Rocker unit for boogie
Lateral motion 13 mm
Vertical motion (lift) 13 / 5 mm

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DanSmo
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Re: Union Pacific Big Boy 4012 in 1.5"

Post by DanSmo » Sat Jan 16, 2016 7:27 pm

Richard, I'll be sure to head over and check out your thread, thanks for the link. I do have the UPHS CD, yet another invaluable tool.

Asteamhead, 2 cents? that's more like $1 and very much appreciated!! I've run your formula a few times and so far I'm inclined to agree with you, I will be increasing the lateral movement. Just after posting I noticed a note on the UP drawing that says the full size locos had a lateral movement of 6" either side of centre which equates to 5/8" on the model. I doubt I'll get that much but I'll try, there is a fair bit of material I can remove from either side of the pivot plate. So far the whole assembly has been made exactly as Rogers drawings show.
I just don't understand pronouncing solder as "sodder"... where did the L go?

RET
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Re: Union Pacific Big Boy 4012 in 1.5"

Post by RET » Sat Jan 16, 2016 9:38 pm

Hi Dan,

I also have William Kratville's book (it came with the Big Boy together with the appropriate issues of Modeltec that covered both the Roy Johnson Four Aces model and also the ones that covered Big boy). The book is a good source of information but the drawing CD is really the prize. The Four Aces Modeltec issues were included because Gerhardt used the throttle design from that model in his version of Big Boy. I also have 3 Big Boy DVD's from Pentrex and they too are a big help to see all twentyfive locomotives in action. When you are doing a project like this, there is no such thing as too much information.

By the way, all those pictures you see of steam locomotives throwing big clouds of black smoke up in the sky are totally misleading. It supposedly gives a better picture to the uninitiated, but I don't like it because it is completely artificial. In practice, if a fireman and engineer actually ran a locomotive that way they would be fired for allowing so much unburned fuel to go to waste. A properly run locomotive would be notched up as much as practical and the exhaust would be grey-white in colour.

Again, as everyone else has said, I too am impressed. Keep up the good work. Looking at our model, you have a long way to go, but the journey itself is rewarding.

Richard Trounce.

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DanSmo
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Re: Union Pacific Big Boy 4012 in 1.5"

Post by DanSmo » Sun Jan 24, 2016 2:57 am

Got plenty of time to myself in the shop this week and made progress on the engine truck. I had to cut some large radii on the centre bolster to allow the side frames to articulate properly. For this I fabricated an angle plate jig for the rotary table that correctly orientated the casting. The side frames were a fairly uneventful process. The only thing I might have done unconventionally was to hold them with the bottom sides facing each other in the vice and mill the journal box openings in both castings at the same time. My theory is that they'll now be a 100% square and matched set. Drilling the holes for the journal box keeps lengthwise necessitated using the T slots on the front face of the bed to clamp the castings, with the mill head extended out and swung to the side it was fairly easy. I didn't take and photos of the set up, the thought didn't cross my mind.

The journal boxes were machined together as a pair, fairly straight forward again. The difficult part of the one piece journal box design is boring for the bearings and seals from either end and having them line up precisely to prevent binding. To achieve this I fabricated a jig from a few steel offcuts. With the jig in the vice I milled an opening that was a close sliding fit with no play for the journal box castings. Without moving the jig in the vice, I then took a cut from the top and finally a cut from the bottom plate so the jig sits perfectly square when clamped down to the bed. Once I had the jig bolted down and dialled in on centre I locked the x,y & z axis on the mill and used the quill feed to do the boring. It worked perfectly, once the bearings and seals were pressed in the axle slid in with no issues and spun freely on the needle rollers.
Attachments
2016-01-14 22.35.46s.jpg
Cutting the large radii on the centre bolster with the fabricated angle plate jig.
2016-01-20 18.54.36s.jpg
Milling the Journal boxes, a good, sharp, long series mill made light work of these.
2016-01-24 14.05.46s.jpg
Boring the journal boxes in the aforementioned jig to keep the opposing bores aligned. This process was repeated 4 times and worked excellently.
2016-01-24 15.55.07s.jpg
Needle rollers and oil seals pressed into the journal boxes.
2016-01-24 15.56.36s.jpg
Assembled engine truck
I just don't understand pronouncing solder as "sodder"... where did the L go?

kvom
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Re: Union Pacific Big Boy 4012 in 1.5"

Post by kvom » Sun Jan 24, 2016 8:08 am

Wayne Godshall is building a Big Boy for a customer. It was not at CF, but the partial FEF was. Wayne stated that the valve gear for the two are the same, so he'll be doing both at the same time.

RET
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Re: Union Pacific Big Boy 4012 in 1.5"

Post by RET » Sun Jan 24, 2016 9:15 pm

Hi Dan,

I see you are at the stage of doing the axleboxes. One thing you might consider is drilling each axle end (both on the main axles and the leading and trailing trucks) and cross drilling in the plane of the needle bearings.

Martin Evans of Model Engineer fame showed this construction for oil lubrication for his 7 1/4" "Dart" locomotive. I thought that was a great idea, but instead of oil, I thought grease would be much better so I made that change for my version of Dart. Once the drilling is done, Drill and tap the ends of the axles for # 10-32 or bigger, and make up a fitting with a grease nipple on one end that you can screw into the axle ends for greasing. When you are finished, just screw a # 10-32 socket hd. cap screw into the threaded hole until you need to grease it again in a year or two.

As you can see, the new grease pushes the old grease and dirt out of the bearing. With this system, you should never have to replace a bearing. I like simple and effective ideas. I also like using Viton "O" rings for sealing.

Hope this helps.

Richard Trounce.

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DanSmo
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Re: Union Pacific Big Boy 4012 in 1.5"

Post by DanSmo » Tue Jan 26, 2016 6:27 pm

Richard, yes i considered doing something similar but I'm using pre-hardened and ground bar stock for my axles which means further machining is not an option. Instead I've drilled a fill hole in the top of the journal box and a drain hole in the bottom, that way i will be able to fill it with oil, then later drain it when it come time for a service... just like in full size. The drain plug will also have a magnet in it to trap metallic particles just as many automotive applications do.
I just don't understand pronouncing solder as "sodder"... where did the L go?

VK2DJ
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Re: Union Pacific Big Boy 4012 in 1.5"

Post by VK2DJ » Fri Jan 29, 2016 2:43 pm

G'day Dan you have taken on quite a build project a Big Boy is quite a challenge & a very long term task but if you treat each part as a project in its self you will eventually see the light at the end of the tunnel ,I started my build of a Victorian R class & thought it was going to be a 5 year project but after just on 5 years so far I still have long way to go ,with all the small detail parts it takes time your work so far is to say the least is impressive & I will be following your build with interest.
There was a fellow in our club that started a Big Boy in 5" about 20 years a go but has since left our club & as far as I know has still not finished it
You may have already seen this chaps build but I will post the link anyway
http://modelengineeringwebsite.com/Big_Boy_build_1.html
Keep up the good work
Gary

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