Workbench: BR 21 ton hopper

[Richard Phillips]

Some of you might have seen the progress on Dave's kit at Gilling, so here are a few photos of it in construction.

[Dave Noble]

Lovely job Richard, just like the real thing, will be a pity to paint it.

I've restarted on mine, made a new body as the old one was just a trial from scrap pieces. Will post some pictures after the weekend hopefully.

Wonder how Paul is getting on with his.

[Richard Phillips]

Wonder how Paul is getting on with his.

That's Paul's chassis in the second photo in my living room/workshop, he mentioned something about needing more parts or something.... I'm sure the MOD and the milk tank will be keeping him busy.

My hopper is now boxed up for the move (probably next week), so the last bit of solder has now splashed on my carpet in that house. I've had enough of soldering for a while now, I think I prefer riveting!

You might be able to see my alignment pins in the side of the solebar in the last photo, they were knocked in - a tight fit, the body is still detachable at this stage.

[Dave Noble]

At last I've made some progress on my hopper.

Unlike Richard, I assembled mine by soldering the vertical corners of all four body panels together first, then bending them in and soldering downover. This may have been a mistake, as the opening for one of the bottom doors isn't as square as it should be, and the 3/32 alignment pins, don't. This requires some rethinking.

I did follow Richard's advice and used uncored solder and Baker's fluid. It works very well, much better than the cored solder which I used originally. Unfortunately, as you can see, it is very corrosive and everything eventually rusts.

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Richard used a small oxy/propane torch as his heat source, I used a 100 watt electric soldering iron. As you can see, I overdid it a bit with the amount of solder. I think this is because of the flux, being so corrosive, it eats away at the soldering iron bit very quickly. This means that the bit has to be reformed, and I was lazy and didn't keep a sharp point on it as I should. It soon ended up with a point of about 90 degrees, so that when it was run down a joint, it encouraged the solder to flow further than I wanted.

What I did get right was to tin all the joints before assembly. This helps a lot, and makes assembly quite quick and easy. You can see the tinning for the side stanchions below.

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I want to be able to rust this wagon after painting, so all surplus solder has to be removed. I was fortunate to be able to use a grit blaster. It was fairly slow and very dirty, but to see the surplus solder just "disappear" was brilliant. The joints are now much neater.

21t clean end.jpg (47.3 KiB) Viewed 293 times

Next, I will reform the soldering iron tip properly, and see if this produces finer fillets on the side stanchions.

[Richard Phillips]

Looks great! You seem to have gone for the "sawn off" handrail, a variation I wish I'd though of, it's probably easier. The one common thing about the handrails is they were virtually all bent in service I think!

I'm envious of how you've managed to get the corner so sharp, I'll have to do a bit of filling in some of the areas where the castellations come together. It seems you, like me, will have to drill a rivet out of one of the axleguards to get the brack rack support in.

My hopper is now in a box now travelling to it's new home, the pins should come out, and did help to keep the side stanchions in the right place for soldering.... please don't tell me they are in the wrong place!

I think the soldering iron wins out on neatness, although sometimes the solder seemed to flow right and quickly, and other times it didn't.

Be interested in how you get on with the side stanchions, I remember you saying you were going to tackle them a different way to my sub-assembly method!

[Eddyg]

I think you are all doing magnificently with your hoppers. I'm afraid my LNER 20 tonner is stagnating, since my locomotive building activity is taking all my time. I have done some work and have the wheel sets and axleboxes done as well as some other bits and pieces, which have been machined when set ups for the locos have been convenient for making wagon bits.

Soldering steel is not too tricky and you both look as if you have the technique sorted. One of my locos has a soft soldered steel cab, and has had for over 30 years, but escaping steam and condensation inside the cab ultimately penetrates the paint and starts corrosion, which gets under the solder and eventually breaks the joints. I've spent many happy hours scraping out the rust, re-soldering and repainting over the years. I often use cored solder with baker's fluid (Killed spirits they used to call it, but I can't remember how it's made - zinc in hydrochloric acid comes to mind), but like all soldering, cleanliness is next to godliness and is the secret of success. Once done of course the flux must be thoroughly cleaned off before applying paint, otherwise the corrosion will be built in and the joints will suffer.

One thought on the material was that tin plate would make soldering a lot easier and neater if a supply could be found of suitable gauge, (memories of making cake cutters at school) and this would make painting much easier. I can't say I've seen anyone advertising the stuff in recent years though, but I'm sure it must still be available.

I'm not sure if it was Richard or Paul who showed me the 21 Ton hopper at Gilling this year, but I have to thank whoever it was for the enlightenment on the hopper door gear. I had spent a lot of time trying to work it out, but the vehicles I was looking at at Shildon appear to have bits missing. I suspect the gear has been gas cut to release the doors to empty the wagon prior to consigning them to scrap and corrosion has done the rest. Anyway I know how it works now, so I can finish the drawings, when I get some time.

Keep up the good work, and remember you only need another 27 to make up a proper train for Steve's Q5!!

[Dave Noble]

With all this good weather we've been having, I've spent more time gardening than building the hopper, but now with the change, I've got the side stanchions on.

As suspected, reforming the soldering iron tip helped a lot, the soldered joints are generally much neater.

21t 2, joint.jpg (24.35 KiB) Viewed 224 times

I fitted the stanchions differently from Richard, though not as planned. Richard, I think, silver soldered each of his up as separate assemblies, then soft soldered each in place. I wasn't sure that I could keep them exactly the right shape as separate items, so intended to fix the body and underframe together, then build up each side stanchion in situ. Unfortunately, there just isn't enough room to get a big soldering iron into the small space by the longitudinals. I therefore kept the body removeable, but relocatable using a small block of brass at each end soldered to the end stanchion stay. A 10BA bolt from underneath keeps the parts together and lined up, you can see a block in one of the photos. Each stanchion was tacked in place (using uncored solder on the iron), then the body was removed and the joints fully formed (using cored solder fed into the joints). This worked fine.

21t 2, general view.jpg (29.45 KiB) Viewed 224 times

All the stanchions are in place and I think all the soldering on the body is now finished, except for fixing to the underframe of course. Grit blasting is only partly done, but should get finished next week. I pickled the body first to try and get rid of some of the hidden rust and redissolve hidden Bakers Fluid, then after drying, started the grit blasting. Unfortunately, part way through blasting, the outlet hose came off the pot, and as it was next to me, and I was kneeling and only wearing shorts, it deskinned part of my calf, no comments necessary. In the ensuing lunge, I seem to have broken one of the end handrail stays off which makes me think that perhaps they should have an unprototypical bracket on the inside for strength.

21t 2, general view 2.jpg (34.37 KiB) Viewed 224 times

You seem to have gone for the "sawn off" handrail, a variation I wish I'd though of, it's probably easier.

No, not really, realising that the side bracket for the end handrail would be vulnerable, I only fitted the short rail as a temporary measure to support it, though as I mentioned above, I still broke it off.

It seems you, like me, will have to drill a rivet out of one of the axleguards to get the brack rack support in.

Yes, quite right, I didn't spot that either.

One thought on the material was that tin plate would make soldering a lot easier and neater

Probably so, but it would also result in an unrusty wagon, and I think these wagons should have at least some rust on them.

[Eddyg]

Dave,

I always thought that models were built in ex works condition and then painted to look rusty. I suppose leaving them to rust saves a bit of work!!

My photo is of the 20 tonner at Shildon which is just a bit rusty, to the point where it wouldn't hold 20 cwt of coal let alone 20 tons. I guess that if they hadn't got it inside when they did there wouldn't have been a body by now. They also have a rebuilt 21 tonner there which is still parked outside. It is to be hoped they get it indoors soon.

Eddie

[Dave Noble]

I've made some more progress.

The door operating shaft brackets were etched in steel with the side stanchions, they just needed a bush and strip of steel soldering in, then shortening.

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The brake lever guards are a little different from normal because the bottom the two legs are not joined directly to each other, but are bolted around the stay. The bits were laser cut as a strip (I missed one of the holes out of the short bit) and after bending, silver soldered together. I was a bit anxious about the acute bend in the stay, but my little Warco bender did it with no trouble.

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As you can see, these bits have been added to the underframe. I've also added some more bracketry as pointed out by Richard, and other fixed bits.

P1010527.JPG (39.74 KiB) Viewed 66 times

It's now ready to solder the body and underframe together, when this is done and cleaned up I'll feel I'm nearing the home straight.