Converting a USA Trains diesel motor block to a 4-coupled steam loco

[gregh]

THE PLAN – to convert a USA trains diesel motor block into a 4-coupled steam loco.

I bought this block years ago, but it has very small wheels (27mm) and I never used it.


Last year I bought 3 Bachmann Big Hauler motor chassis to replace some of my existing ones with noisy gears etc.  So I now have spare Bachmann wheels (50mm) etc.


The axle spacing on the USAT block is 85mm so I thought it would make a reasonable 4-coupled loco if I could fit the Bachmann drivers to it. The Bachmann axles were easy to remove and the wheels pulled off the axles with a bit of force!  The wheels have a plastic insert to isolate the wheels from the axles, with a 5.3mm hole.





The USAT bottom cover is removed by 4 screws and the 2 axles lift out.


I had to put the axles in a vice and knock the axles out of the wheels using a hammer. The axles have a long  3mm dia extension (for bogie side frames?) which I ground off. The axles are 4.0mm dia, smaller than the holes in the Bachmann wheels so I split some 4.75 mm OD brass tube to be a push fit on the axles and superglued them, after a good clean in metho. You can see the brass ‘ends’ in this pic.


The Bachmann wheels were a push fit onto this, so I superglued them too, making sure the wheels were ‘true’ on the axle (difficult) and the conrod connections were at 90 degrees (very difficult).  I cut down and spliced the original Bachmann rods – we’ll see if they last or if I need to make brass ones.

So here’s the final result.


Then it was time to do some testing, before starting to build something with it.
So I hooked up an open wagon with battery and meter, and put an old transformer on the motor for weight and checked it ran OK. Total motor +transformer weight was 950g hauling a 4kg, 12V battery on relatively level track, on a 800mm rad curve.  Speed about 45kph @ 12V, so I’ll need at least 10  AA cells.
I think it’s a ‘goer’ !!


Now to build the loco….. to be continued

 

[ge_rik]

Marvellous ingenuity, Greg. Will follow the rest of the build with interest.

Rik

 

[JRinTawa]

Very clever

 

[stockers]

Nice one. With nice big drivers there must be lots of possibilities.

 

[gregh]

[quote author=stockers link=topic=301079.msg349338#msg349338 date=1429723703]
Nice one. With nice big drivers there must be lots of possibilities.
[/quote]
Well I wish I could get some inspiration.  I`ve thought of 2-4-2 tank locos, but it looks too similar to my existing 2-8-2 and 2-6-4 tanks.
Also, I realise now (too late) that it`s going to be difficult to support the body on just the short block with long overhangs.  I can`t figure how to use the pony trucks to support the back and front. 
I need some HELP on different shapes for tanks.  Maybe a pannier?

I would love an American 4-4-0 tender type , but the same support problem applies.


So today it seems I`ll be looking more at a small 2-4-0 tank or 0-4-2T.  But then there`s the problem of fitting the RC, batteries and speaker in.

all ideas welcome !!

 

[dunnyrail]

Well I wish I could get some inspiration. I've thought of 2-4-2 tank locos, but it looks too similar to my existing 2-8-2 and 2-6-4 tanks.
Also, I realise now (too late) that it's going to be difficult to support the body on just the short block with long overhangs. I can't figure how to use the pony trucks to support the back and front.
I need some HELP on different shapes for tanks. Maybe a pannier?

I would love an American 4-4-0 tender type , but the same support problem applies.
[attachment=0][/attachment]

So today it seems I'll be looking more at a small 2-4-0 tank or 0-4-2T. But then there's the problem of fitting the RC, batteries and speaker in.

all ideas welcome !!

Gregh, I think your 4-4-0 may work. If you used some good solid pipe like say Plastic Drainage you would have a solid 'Chassis' in effect. Then a Front Bogie mounted should do its job and support the Boiler. The Chassis that you have was used by myself in one of my Railcars Andy Rush used them in his too. You can utilies the Screws that hold the Top on with Plates mounted by using them to secure said plates. Try a lash up to see if you can get it to work for you.

Of course a Steam Tram or Dummy as the Americans call them may give you more space for Batteries should you go down the Tank Engine route in the end. Or even a Price, but then you now have the wrong wheels!

You do have the benefit of not worrying about the Bachman Wheels for Pickup being a Battery man as it were. Bet you had some fun with the Quartering? Good luck with this inivitive concept.
JonD

 

[ge_rik]

How about a single Fairlie? You could make the power bogie swivel as well as the trailing bogie.


Rik

 

[ge_rik]

Alternatively, if you fancied repeating the modification ....


Rik

 

[gregh]

Gregh, I think your 4-4-0 may work. If you used some good solid pipe like say Plastic Drainage you would have a solid 'Chassis' in effect. Then a Front Bogie mounted should do its job and support the Boiler. The Chassis that you have was used by myself in one of my Railcars Andy Rush used them in his too. You can utilies the Screws that hold the Top on with Plates mounted by using them to secure said plates. Try a lash up to see if you can get it to work for you.
JonD

I have to admit my skills don't seem up to figuring out how to do the front support. I'm guessing, it would have to be a slot across the part fixed with a pin on the bogie, sliding in it. The Bachmann big haulers have a similar thing, but they don't really support the boiler.
In my case I'd also have to be careful to check I could get enough 'swing' on sharp curves.
Thanks for the idea of using the existing screws on the top. I was thinking of that if I go the 2-4-2 route. Is good to know it's possible.

Following Rik's suggestion of a Fairlie, maybe I could pivot the 4-4-0 on the motor block, and then a simple pivot on the front bogie. I wonder how it would look.

 

[gregh]

How about a single Fairlie? You could make the power bogie swivel as well as the trailing bogie.
Rik

While it's cute little loco (did we see it at Porthmadog?), I want to show off the big wheels. BUT the idea of swivelling the motor block is good thinking 'outside the square'. I'll play around tomorrow.

 

[ge_rik]

While it's cute little loco (did we see it at Porthmadog?), I want to show off the big wheels. BUT the idea of swivelling the motor block is good thinking 'outside the square'. I'll play around tomorrow.

Yep - she was the one hauling the night train (your video turned out far better than mine).

Rik

 

[dunnyrail]

Gregh,
A similar Front Bogie support to the Bachman was what I was thinking but with perhaps a bit of Spring Steel as a Bogie Holder and a Spring should cut the bill. Plenty of Weight up front should make sure that it is doing its job.

Another option, Pld Coppernob would give you a Tender. See link below:-

http://www.nrm.org.uk/OurCollection/LocomotivesAndRollingStock/CollectionItem.aspx?objid=1975-7015

Though she is British, must have been similar old babies out your neck of the woods.

Must say I do rather like the Fairley. For the Bogies on our Railcars Andy and myself used the plate idea then Soldered a beefy screw to it to act as a pivot. You do need to think about some rubbing plates on the chassis as well to stop Bogie Flop for any articulation.
JonD

 

[gregh]

Alternatively, if you fancied repeating the modification ....
[attachment=0][/attachment]
Rik

Josephine's a nice loco. If I remember it's preserved in Dunedin NZ - the pic has the station in the background.
I'd have to finish converting another Bachmann to new motor block, to release some more wheels.

 

[gregh]

[quote author=dunnyrail link=topic=301079.msg349443#msg349443 date=1429856196]
Gregh,
A similar Front Bogie support to the Bachman was what I was thinking but with perhaps a bit of Spring Steel as a Bogie Holder and a Spring should cut the bill. Plenty of Weight up front should make sure that it is doing its job.

Another option, Old Coppernob would give you a Tender. See link below:-

http://www.nrm.org.uk/OurCollection/LocomotivesAndRollingStock/CollectionItem.aspx?objid=1975-7015

Though she is British, must have been similar old babies out your neck of the woods.
JonD
[/quote]
I did some lash-up testing today and the 4-4-0 american just won`t work - the cylinders will foul the bogie and it will look weird with the small boiler swinging way out at the front and no `baseplate` to cover the `workings` of the bogie.  Anything with cylinders won`t work.

I was almost decided on this loco,


but now you`ve offered Old Coppernob. That`s a beauty, but how on earth would I model that dome and the tee connection to the boiler?

 

[JRinTawa]

Josephine's a nice loco. If I remember it's preserved in Dunedin NZ - the pic has the station in the background.
I'd have to finish converting another Bachmann to new motor block, to release some more wheels.

Yep Josephine is preserved at the Otago Early Settlers Museum http://www.toituosm.com/whats-on/exhibitions/josephine

 

[gregh]

Yep Josephine is preserved at the Otago Early Settlers Museum http://www.toituosm.com/whats-on/exhibitions/josephine

Was in a big 'glass case' at the station when I saw it (about 10 yrs ago)

 

[gregh]

So after much procrastination and perusing many pictures on the web, I think I`ll go for something like this one.


I used a piece of 3mm x 25mm alum to make a support bracket on which the body will sit.  As suggested by dunnyrail,  it is held to the motor block by the existing screws.  Notice I had the put a `set` in it to get the footplate at the correct height. The boiler will sit on top of the bracket.


Once I get all the body built, I`ll have to `balance` the fore and aft weight as the front bogie does not support any weight.

The footplate is a piece of 2.5mm styrene, cut for the motor and wheels to protrude up.


I made up the front bogie from 12x12x1mm al angles and a hunk of lead, and some plastic wheels. It pivots on a bar, back near the motor block.  And ran it through some sharper curves and turnouts to check it worked.


I then took the pic of the ` dream ` loco and drew `boxes` around it to repoduce a drawing of my proposed loco, sitting on the photo of the wheels.  I was worried that I had too much overhang at the back, but have decided I can live with it.


The boiler is 56mm OD electrical conduit with some 0.5mm styrene wrapped around for the fire and smoke boxes.  Here`s the `mock up`


And that`s the progress so far. Now it`s just details!

I haven`t  decided whether I`ll put a LiPo battery in the tender, with the RC gear in the boiler, pushed in from the removeable firebox backplate.  I`ll then need a fair amount of lead either in the boiler or glued under the motor block.  Or use 10 NiMH cells in the boiler for weight.
But the sound system and speaker WILL be in the tender.




…… to be continued.

 

[PhilP]

Looking good.. will follow with interest.

 

[gregh]

A bit more (slow) progress. I seem to spend most of my time waiting for glue or paint to dry.

The boiler and cab are complete and painted. It looks a bit ‘toy-like’ in this pic but I hope the addition of some details, handrails and lining will help.


I turned the smoke box from Masonite and the dome from hardwood and added a few styrene details.
The funnel is plastic elec conduit given a slight taper in the wood lathe.


The tender body is a 2.5mm styrene box, covered with 0.5mm styrene with rivets embossed. 
The fake springs are made from layers of cardboard.  I have to decide whether to paint the springs etc a different colour to highlight them. Grey?
The wheels run in some 25mm aluminium angle. I only had plastic spoked wheels, so I wrapped thin lead sheet around the centre axle and slotted the ‘axle boxes’ to allow it to move up and down.  It has an extra 6mm side play so the whole thing does go around R1 curves.


I’ve used two, 1000mAh LiPo batteries connected in parallel, to give 12V and 2000mAh capacity. They are in the tender with an oval shaped 4 ohm speaker facing downwards and a sound circuit using my favourite - the Picaxe.




The RC receiver and ESC are Hobbyking, hot-glued together. For reversing, I use a servo with a DPDT switch glued to the side. This and the Rx+ESC are glued to a piece of corroflute and slip into the boiler by pulling the smokebox door off.

The red 2-pin plug goes to the motor.
A 3-wire ‘servo’ type plug/socket connects the tender to loco carrying +12V, 0V and the motor voltage back to the sound circuit.

Now to wait for all the fiddly bits to dry and put it all together.

Hopefully, the next report will have it all together and running.

 

[ge_rik]

Excellent work, Greg. Really like the way you've solved the problem of the front end overhang and the way you've maximised space in the tender. I know what you mean about waiting for paint to dry.

Rik