Full Version: VGN 2-10-10-2 - my 2014 challenge
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In last days a have done last small changes at my recent car projects and now I must wait for help or next steps which should done by friends, painting or help for construction for 3D-printing. So I can change to my long time planed rebuilding project - the Virginian 2-10-10-2 class AE. I know I have postet a few pictures of my model already and now it must get a reworking! So far, the model is a bad runner that I want to change necessarily.

[Image: vgn-ae_001kk.jpg]

[Image: vgn-ae_002kk.jpg]

[Image: vgn-ae_003kk.jpg]

[Image: Virginian_Railway_AE.jpg]

Here yet a picture of one of originals - a free usable picture after rules of Wikimedia Commons.

Again a few highlights because I love this engine.
The AE was built in 1918 by ALCO and it was at this time and also until to end of this loco type in 1952 an absolute giant!
- Pulling power 147,200 lbs (working as compound engine) and 176,600 lbs (as simple working engine with high pressure steam to all four cylinders).
- The biggest cylinders ever used to a steam engine (30” high power and 48” low power, both 32” stroke) – for readers in metric dimensions: dia 762 mm and 1219 mm by 813 mm way.
- The biggest ever used boiler diameter 118” (outer dia.) or 2997 mm.
- Biggest wide at front cylinders 144” or 3658 mm.
- Weight on drivers in working orders 617,000 lbs.
The engines were so large that the must moved from the erecting shops to the VGN with removed front cylinders and without the cab.
What for an engine and built in 1918 already. See also the long living time – until 1952.
Their only problem was the extreme slow max. speed, only 15 mph or 25 km/h because the small driver diameter, the big piston stroke and the extreme high masses of pistons, crossheads and rods – however it was good enough for pulling extreme heavy coal trains over steep grades while 35 years of life! Can you discover my enthusiasm for this engine?

Now I will start to give the model a new life and I would like to add a few better features as that what mass produced models have.

[Image: vgn-ae_013kk.jpg]

[Image: vgn-ae_015kk.jpg]

In last year already I repaired a missing knee at one of steam exhaust pipes, but this was only a beauty repair without many work.
What I mus do these are these very bad realized solutions.

[Image: vgn-ae_022kk.jpg]

The picture shows an extreme bad working power transfer from motor to rear driver group by a hard and heavily bent hose ...

[Image: vgn-ae_023kk.jpg]

... and a too short and hard connection from rear to front frame.

[Image: vgn-ae_025-2kk.jpg]

In result all the front drivers are hinging over the rails if the rear drivers run about a small bump on tracks. The mobility of the front frame is severely limited by the extremely inflexible gear connection to front-frame, so the entire weight of the locomotive is focused on the rear engine - and this must be changed! Basically!
Now I startet with a scetch of loco and I compared it with a drawing of original. So I hope to get a good base for all the changes which I would like to realize.

[Image: vgn_ae_drawing_comp-engl.jpg]

To be continued.

jwb

It's worth pointing out that they were built for the line west of Roanoke over Clark's Gap, which was electrified in the 1920s. They were then moved to service east of Roanoke, which had a crossing of the Blue Ridge (a helper grade eastbound on the N&W) that was almost entirely downgrade for loaded trains. The few videos of this section show a lot of tunnels in pretty spectacular scenery, but operationally it was pretty easy going. (This was the typically remarkable engineering of the VGN, although as a late-built line, it had to have some advantage over earlier ones.)

Their power probably wasn't needed on the line east of Roanoke, and the AG 2-6-6-6s were the locomotive of choice for coal trains after WWII.
jwb, thanks for your friendly addition.

A short addition to last picture.
The biggest difference of model to original drawing is a lengthened wheelbase. Front like rear drivers are a bit wider positioned so that each is 0.1" longer than original. Also LP cylinders are moved to front for this value and all in all the model is also 0.1" too long.
In fact I do not need this comparison but I need exactly a few measurements in order to set new motors, yes motors and not only one motor, gears and all other to new positions.

First thing I want to change is the frame and axle mounting. No more fixing - all wheelsets should be movable! Here is my plan.

[Image: vgn_ae_frameconstr-engl.jpg]

You can see that the fourth und fifth wheel sets in each driver group will get working driver equalizer. The two mounting points of equalizers are the two rear support points for the model. The two rotation points of the equalizer are the two rear support points for holding the model during the three leading wheelset of the rear group are pressed with springs on the rails, but such springs which are softly enough so that the wheel sets can move up and down. All rear equalizers are externally mounted to the frame flanges and they will sit with their ends on the axle bearings. Unfortunatel there is not enough room for an inside mounting.
The front driver group has a third driver equalizer for first and second wheelset which is positionid in center of frame. It gets new bearings in center of axles so that they can move up and down and swing laterally too. So I get a local three-point balanced front frame together with a soft sprung center wheelset. This frame gives a new and the third support point for the boiler front with a new glideway that not existed at model in moment. How I have said - all will be movable and all wheels will on rails assisted by a changed motor and gear conception.

[Image: vgn_ae_gearconception-engl.jpg]

Also the motor and gear conception is changed.
I will use the original axle gearboxes also with new concept because they well usable and they have a 1:44 ratio, I think a good value. What I will change as first - the gear box of rear axle group moves from first to last axle.
So I can build two absolutely independent motor and gear systems, one for each driver group. All gears are fix mounted and the connections to axle gearboxes will realized by universal ball-point connections. However, my "gears" are realized by simple rubber ring components, rubber rings and small belt pulleys. So I can realize additionally to the 1:44 gear ratio of axle gear boxes a more reduction of 1:1.5 or 1:2 and I get an optimal motor speed of 7.000 or 8.500 rpm.
My big vantage should be that I can built all by scratch and I must not try to use commercial products. And there is a great problem. I have studied the NWSL catalog and there were no parts which I could well combine with these axle gear boxes. With my solution I can set the motors on levels and positions in boiler where they will have their best place. I can mount all shafts of gear systems in a horizontal line and at last, I do not have problems with small differences in measurements and materials; they will be eliminated by the rubber band drives. And I so think that I have found a good solution -
... a good solution for my absolute dream in use of mallet or articulated steam engines.
I hate to see how the running gears of all models of articulated steam engines run foot by foot, meter for meter, and after many rounds on a layout the running gears are in an identic position to each other. This is a fact very far of reality! I hope for a new view on model steam locos, changing of position of running gears and to see slipping wheels of one of driver group and I think that this will be reality with my system without additional changes, because the weight pressing on front wheels is a little bit smaller as that on back wheels. And if this will not be enough to achieve these effects than I should install a second decoder for front unit that will get a little bit more start voltage. Or?

What do you think? All your ideas and discussions are welcome! Thanks for all your answers!

And as last. Open description on my website for a few more pictures of original locos, as double back end helpers or with an exploded boiler.
The "cup and ball" drive shaft couplings are far better, and far more flexible that the "hoses". That 2-10-10-2 ( "Beast" )
should run much better with that change. The twin motor idea looks good to me.
What is the sharpest curve this loco will have to "get through" ?.......that is a Loooooong wheelbase ! :o Eek :o
Sumpter, thanks for your your comment.

I must say that I had made test runs with this model only on a straight track. Not good and that gives not an answer.
But I think there are not a big problem. You can interprete this loco as two very short coupled 5-coupled engines. I think that there will be enough flexibility with the new connection between two frame halves. And maybe you can recognize at my drawings, better yet on pictures, that each wheel group has two flangeless wheelsets in center - in numbers wheelsets 3 and 4 and 2 and 3 in rear group.
My 'main' area of operation is a big modular arrangement at US FREMO in Unna, Germany. The radii are not lesser than 40" together with #8 switches, in a few cases also #6. In all cases I can run the engines and my train on straight track over the whole layout - except for switching on staging yards. There are #6 switches how I know. So I must see how it will work in these yards.
Just out of curiousity , what kind of turn radius does this beast require?
MountainMan Wrote:Just out of curiousity , what kind of turn radius does this beast require?

MountainMan, read my post before, please. Thanks.
Bernhard,

i hope you'll win the challenge. Thumbsup

It must be a very good looking steamer on the layout like your camelback.
Joerg, thanks.
I hope for completation until Mai/June in next year. Than is the yearly Fremo meeting in Unna again.
Bernhard, the Bachmann Consolidation uses a cogged drive belt and you may be able to purchase both the belts and the pulleys as individual parts. You can check it out HERE.

Wayne
Doc, thanks.
I think that I will use rubber rings. They are available in a wide range of sizes and they work well. And I can get replacements for a very long time if needed. I plan to use a twin ring for a light run, with lesser pre-tension but identical friction. And use of ball-bearings at driven axles. Ok, all a bit more work but I'm sure to reach success.
Thanks again!

jwb

One question I have is whether the motor for the front unit, turning inside the boiler with the front unit, will have enough clearance to allow the loco to make any kind of reasonable curve. That would be worth a check, maybe making a full-size mockup in cardboard or whatever.

To my way of thinking, running model locos involves many compromises -- commercial articulateds now have the rear unit turning as well as the front, and model duplexes are articulated when they shouldn't be. Both of those are more severe than just having front and rear units running always in sync, to my way of thinking. The sound decoders play the units in and out of sync now anyhow.

One of the brass manufacturers also did a Santa Fe 2-10-10-2 -- the reviews of that also said it would pretty much only run on straight track.

It might be worth looking into the Northwest Short Line HI-LO gearboxes, which have a different approach to connecting the units of an articulated together -- a single motor mounted high in the cab or firebox, which drives via a forward-slanted cardan shaft via a rear gearbox with idlers that sits high, and a front gearbox that sits low. <!-- m --><a class="postlink" href="http://shop.osorail.com/category.sc?categoryId=174">http://shop.osorail.com/category.sc?categoryId=174</a><!-- m -->
jwb Wrote:One question I have is whether the motor for the front unit, turning inside the boiler with the front unit, will have enough clearance to allow the loco to make any kind of reasonable curve. That would be worth a check, maybe making a full-size mockup in cardboard or whatever.

If you look at the drawing again, the motor in the boiler, for the front unit, is connected to a drive shaft, mounted in the cylinder supports of the rear engine's cylinders. the only thing that moves with the front engine is the drive shaft (cup and ball)
to the front engine's geared driver axle.
My 3' gauge outside frame 2-4-4-2, uses the same drive system but with only one motor ( actually mounted in the tender ), and it has been basically trouble free for over twenty years. ( I cured the "dirty wheel electrical pickup problem" by hauling a track cleaning car, (( box car with a weighted pad under )) to keep the rails clean )
jwb, thanks for your interest. I hope that I can give you full explanation what I would like to da and for which reason I will do it.

My big wish is that both drive wheels must run independently and not in sync.
That needs to install with two motors which run without a coupling or a connection. Both motors will mounted and fixed into the boiler and also the front motor will not rotate. Both rubber bands will drive its own short shaft, both fixedly mounted in the rear frame. So I have two complete drive units, both of which are firmly mounted in boiler and rear frame without any necessity of movement. At end both frame mounted shafts are connected by an u-joint driving with the axle worm gears. The front unit needs this u-joint because of moveability of front frame and the rear one needs that because of moveable axle which will move a bit up and down with the motion of axle equalizers.
I have checked all the gear systems which are available by NWSL and they all do not that what I would like to get. I will got a solution by my "construction" where I do not see one item of the gear beside of the front gear housing a bit of u-joint - not more than now - and better yet for the rear engine. All gear parts are hidden in the ashpan and behind rear steam engine with support for the boiler.
I thank that it will be a good working solution. (I hope.)

And an addition.
This engine is a mallet, an compound engine. If it should I add a sound decoder then you will hear only the chuff-chuff of the front engine. The rear cylinders deliver the exhaust steam to front cylinders and you will hear ... What? Maybe an acoustic noise, also in a rhytmic sequence but not a clear chuff-chuff. This will only come from front cylinders.

@Sumpter, thanks. You was a bit faster in answering.
Bernhard, what you say is absolutely true! A compound Articulated Steam Locomotive, sounds just like a "single"
( one "engine" ) steam loco.
A "simple articulated" has two exhaust sounds, one from each engine, as the "engines" are both operating on high pressure steam straight from the boiler. Those exhaust "chuffs", can happen simultaneously, or in any pattern of syncopation.
Adding sound to a "Simple Articulated loco" can require some "creative timing" in the sound.
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