a 'Joffre' for a museum display

[tedp]

In the Valkenburg museum we have a French theme H0e diorama named 'Morvallon', see photos below taken from the Dutch Group website.





This was built by Anneke Boelens and Len de Vries and donated to the museum about 10 years ago. After years of static display, plans are afoot to restore the diorama and make it operational using a timer switch so a train will run round the circuit. For this purpose I am building a French outline locomotive using the Chivers (FIVE79 RC16) kit of a Kerr-Stuart 'Joffre', almost identical to a 1911 Decauville 0-6-0T.

The kit was meant for a Roco BR80 chassis but I will be using a Minitrix dock tank. These are all right for forward running without requiring slow running performance, and can be replaced cheaply because the chassis is available second-hand at a low price.

I had to adapt the supports for the chassis in the body shell by fitting styrene filling pieces. Also, the smokebox base was built up using styrene. This is a support for the chassis and an attachment for the front buffer beam and coupler. The cylinders were fitted with a wrapper made up of nickle silver strip, but I accidentally used the Kerr Stuart type of inclined valve chest instead of the Decauville type which is horizontal. See this website and this photo to compare: http://appeva.perso.neuf.fr/fest/pent07-13.jpg

Anyway I think this is a good enough replica of a Decauville loco to use on a French 'S

[tedp]

Construction procedure

1. making a start
I followed the FIVE79 instructions except where they say to fix the front buffer beam to the chassis. The kit is meant for the Roco BR80 0-6-0 so it had to be adapted to the Minitrix block. Most construction was done using cyano gel glue. I started cleaning off all the flash which mercifully is thin, then fitted together the cab front, boiler/tank top and the cab/tank sides and smokebox front. Now I could see how the chassis would fit into the body shell, with one eye on the prototype photos found on the internet.

2. fitting the chassis
The problem with the Minitrix chassis is the nearly upright position of the motor which needs the entire chassis to be offset to the rear a few mm, playing havoc with the line-up of the cylinders. In the K/S Joffre these are slightly forward of the smokebox as opposed to the Decauville. So with the roof still off, I filed out the cab front and boiler/tank top as much as I dared to gain a little space. I then adapted the cab bottom so the motor mount of the Minitrix chassis would fit into it, filing two gaps in the bottom to clear the small 'ears' on the motor mount visible in the first two photos.

3. setting up the body shell on the chassis
Following this I fitted the coupling to the cab rear and glued the roof and the cab rear in place. Using a Roco skip I set the coupling height above track so the skip would couple up securely. This was achieved by inserting thin slivers of styrene under the cab floor, as shown in the second photo above. Up to that moment I had to hold the shell and chassis in place AND horizontal with my hands, as the front footplate etc. hadn't yet been set up. A question of trial and error therefore - I might have used a temporary packing piece at the front. With the height set at the rear end, I measured the space needed between the chassis block and the pannier tanks and the internal height to the top of the smokebox. I cut a rectangle of 1mm styrene, 7mm wide, for the smokebox front to support the body shell on the front of the chassis. This was glued behind the smokebox door, and I had the loco sitting neatly on the track. An exact horizontal position of the model is essential otherwise it will never look right. If you look under the tanks in the next photo you can see the supporting piece of styrene:



4. fitting the front footplate and buffer beam
The styrene smokebox front was used to attach the front footplate. In the prototype this is assembled on to the end of the well tank. Again, the first thing to take care of was coupler height. Using styrene cement, I glued a few styrene filling pieces to the styrene smokebox front (the support shown in the photo above) and positioned the footplate on them until the coupler would sit at the right height above the track. The packing pieces can be seen below the front footplate in the photo. Again, a Roco skip was used to determine the height. Some of the styrene had to be filed off to make sure all sat true on the track.

5. final details and correction work
The cab roof is under size when glued on to the fitting tabs of the cab sides.So I glued styrene strips in the gaps, and after the cyano had set, I used a sharp knife and fine sandpaper to flatten them. Other gaps were filled with cyano gel. Probably after I will have applied the primer I will need to do some more cosmetic work. The chimney, dome and sandbox were cleaned up and fitted on the boiler top. Finally I used a soft wire brush in the 12V drill to polish the surfaces I could reach.

On the inside of the body shell I fitted a big rectangle of styrene as shown in the photo below. This was used to build up the remainder of the smokebox where it can be seen under the tanks. The smokebox sides, with a cut-out for the cylinder block, extend a few mm down to straddle the chassis. Final work was fitting the cylinder covers (nickel silver sheet) and valve chest tops (a square of lead), and lead ballast strips under the big sheet of styrene. And before I forget, I drilled out the bolt hole in the chassis, and through the keeper plate, to take the reversed fixing screw of the Minitrix loco. I was lucky in finding a piece of styrene with a correct size brass nut embedded in it to glue under the body shell...



The following merciless close-ups in grey primer show that some extra work with filler and fine emery paper is needed:

[tedp]

Here are a few (preliminary) photos of the painted loco, a few days ago. No number plates or varnishing yet.





Following that, I devoted some time to get the engine running properly. The axle and gear slots were worn excessively, the commutator sparked and there was pickup trouble. Running the engine half an hour each way didn't improve matters. The noise increased, suggesting meshing problems due to the amount of wear. The gears and axles moved up and down quite a bit. So there was no recourse but to remove the keeper plate and put solder fillets on it.

I filed a bright patch on the keeper plate where it had been worn by the axles and put a small solder fillet on each patch after applying some flux. Filing down the solder fillets until the axles and gears are free to move a fraction up and down takes numerous assembly and disassembly sequences until the right amount of freedom is achieved.

One wheel proved to have been glued on in the past with superglue. This had caked the back and now and then interrupted power pickup, stalling the loco. So this was put to rights and the pickup springs adjusted. Finally the motor was serviced. I scratched out the commutator grooves with a fine needle, then ran the motor slowly pushing a small stick, with a narrow strip of fine emery paper glued to it, against the commutator, polishing it.

Running in the loco started with some stiffness - a fillet hadn't been leveled far enough. But gradually, step by step, the loco smoothed out. An hour's running each way improved matters far enough to make it suitable for the museum layout.

I noticed that after the work I have done the wheels stay bright and clean even after an hour of running. Before I reduced the amount of play in the axle slots, they would keep fouling up. I attribute this to the amount of 'skitter' of the wheels on the track. With so much play in the bearings they must have jumped up and down. The noise on the track was terrific, and is now much reduced.

[tedp]

During the past days I did a little work on the 'Joffre', which apart from a driver and fireman is now as complete as I can make it. I added porthole windows, a brass headlight, sand pipes (there really should be four, not two) a blower pipe and a whistle. In addition I made up name and number plates. French engines are rarely named, but I thought I'd put a fitting name on this one. The name and number plates were made up on my computer and printed out. In consequence the nameplates are a bit overscale, but I'm afraid that is the best I can do as smaller characters won't reproduce very well.

The loco was treated with eggshell varnish over the acrylic paint, except for the smokebox, the boiler top and boiler fittings. For a real Decauville there should be a top feed and feed pipes to the boiler, and the front buffer beam should be a different pattern. With the inclined valve chests this is a Joffre however, so let us suppose this one was bought by the railway out of war surplus stock.

The loco is pictured with one of the two Liliput coaches it will run with on the layout. Thursday we put the layout on its new support stand in the museum, and I cleaned the track and managed to run 'Somme' all round it for some time. But before the layout is put back in service we will have to replace the lighting canopy and some of the Perspex windows protecting it from prying fingers of some of the public!

[kebo66]

Ted

Congratulations, what an excellent result. The loco looks brilliant.

[tedp]

Thanks - and this is only a very simple project, using a whitemetal kit and a simple chassis. In all I think the price tag is below 40 pounds. Who said 009 modelling is expensive?  ;D

[Isle of Stoner]

My wife.

John W ;)

[tedp]

 :o