I started on the chassis with 2” x1” channel. The front part is bent and although it is easy to bend after cutting through the flanges, there is the problem of the reverse bend, where an angle piece has to be sawn out and the join welded up. This resulted in some distortion. However, this is a problem solvable by the application of excessive force with a big hammer which soon taught it manners.
The cross members are riveted to gusset plates, which is easy, but putting the rivets into the side members is rather more difficult as there is no room for a conventional hold up. Eventually, I had the idea of using a 3/8” BSF bolt and nut. The head of the bolt was drilled out with a ball nosed slot drill. Then using the nut, I could tighten it up holding the rivet in place for bashing. A slow process, but it worked very well. I used the same method for the next items, the slipper guides for the springs. These are 1½” x 3/16” steel flat, all riveted on and the guides for the rear springs were drilled and tapped ¼” BSF for the stauffer type greasers. The front cross member is also the boiler support. Not liking the idea of hack sawing it out of ¼” plate, I took the coward’s way out and had it laser cut. This is fitted with bolted angles.
I had quite a problem in getting the correct material for the springs, but eventually found a firm in Barnstaple who could obtain some 1” x 1/8” spring steel hardened, tempered and polished. When I brought it back, I was rather pleased that I had purchased a cut-off band saw. With all the individual leaves cut to size, I took them all to Western Steam, and “borrowed” their Roller. After a few arm aching hours, all were curved to the final radius.
Each leaf has a hole in the middle for the bolt that holds them in place and some have a 1/16” hole at the ends for the clips. I had tried drilling a left over piece and thought that this would be an easy job. Wrong! The steel had work hardened during the rolling and any attempt at drilling it just resulted in a ruined drill. Luckily Andy Webb came to the rescue with the loan of a solid carbide drill which made the whole job easy. The front axle is an “I” section with plates welded to it for the kingpin bearings. As it was not possible to get the correct section, I used two pieces of “T” iron cut down and welded edge to edge. The front stub axles are made from 1” square stock, with a ¾” king pin pressed in and welded.
The wheels are another Hindley special - two spoke plates are dished and flanged to be riveted to the outer rim. I started by having the spoke plates milled out on a CNC mill, then just leaving me to dish them and flange the edges. Dishing the plates is easy if you have a large press – I don’t! Eventually I came up with the idea of using a bolt through the centre hole to pull then into shape. That only needed a large flat plate, with packing round the edge of the plate. No large flat plate – the floor is flat! A quick burst with the hammer drill and I had a rawlbolt in the floor and the packing for the edge of the plate was two pieces of plywood from the milling machine crate. A quick application of a spanner to the rawlbolt and the plates were dished in very short order. The flanges are separate strips welded round the edges - the radius being filled in with car body filler. These could then be riveted to the rims. The hubs were machined from cast iron and screwed into place with 6 6BA screws.
Then I needed tyres. Solid rubber strip cut to size from a supplier in Bristol was used. Each tyre was glued together using gel type super glue, and fixed to the wheel with Isoflex, a synthetic rubber meant for roofing repairs. Very effective, but messy! When this had set, each wheel was set up in a mandrel in the vice and a belt sander used to bevel the edges. The back axle runs in a split axle box, machined up from cast iron bar.
The back axle of course has a differential, so now I had to hunt for gears. None of the model engineering suppliers could help despite listing them in their catalogues, but Llewellin’s Gears in Bristol quoted £500 for cutting the gears on my blanks! Then the MD suggested that stock gears might be near enough and quoted £120 for two bevel gears and three pinions! Near enough was quite OK!
The axle is of 1 3/8” diameter MS and needed one end turned down to 7/8” diam for about 9 inches. Borrowing a large lathe with a headstock spindle bore that would accept 1 3/8” diameter made life easy. Thanks Andy Cooke! One flange for the differential gear was then welded on and faced up. The cannon axle was made of the same material, bored out to 7/8” running fit and the other flange welded on. The differential centre which incorporates the brake drum was machined up from a solid piece of cast iron. Happily I had just bought a new rotary table for the milling machine, so making the recesses for the pinions was fairly easy. The rotary table is a vertical/horizontal type so drilling for the pinion shafts could be done at the same setting. Oh yeah? When set up vertically, I had practically gagged the machine and there was no room for the drill chuck! Oh well, take it down, and go and see a friend who had a bigger mill. After all that, it actually worked OK. At this point, I could set the model down on it’s wheels. The drive chain and sprockets were motorcycle parts. The storekeeper at the dealer I went to for them still thinks that I am daft, as I didn’t know how many teeth I needed on each sprocket!
Still one of the (very) few measurements I have is for the chain, which in the original was 2 ¼” pitch, 4”, scale 5/8” which is standard motorcycle size.
While waiting for the boiler (Western Steam) the next items were the coalbunkers, which would have been very easy if I had access to a bending brake. To make two bends in 1/16” steel sheet is not difficult, but getting them at the right spacing and the right radius is! However the makeshift bender I made up worked OK and the rest was easy in comparison. The water tank was also made of 1/16” steel, with riveted joints using ½” brass angle. To prevent rust, the inside was painted with two costs of Isoflex synthetic rubber. Tip for other users – don’t even try to clean the brush afterwards, just throw it away!
At this point, I also made the towing bracket. Something else that will have to be done again, as I didn’t make it long enough to get the pin in when bolted to the chassis!
It was about this time that the boiler was ready for me, so I went to Western Steam to collect it. At this point I realised that the drawing I had made did not convey the weight of the finished article! 80 Kg of copper and 1 Kg of silver solder! Something else I needed help with. The original boiler had a flanged joint in the barrel, bolted up. The boiler inspector would not be pleased if I did the same so that the flanges are only dummy as are the rivets in the barrel to firebox joint. These flanges were obtained laser cut with the bolt holes just spotted in. They are fixed to the boiler using high temperature epoxy resin adhesive.
To be continued