7mm On Heather's Workbench - small and perfectly formed

Heather Kay

Western Thunderer
The Pro-Am 57xx build continued today, concentrating on fitting the suspension and cosmetic springs. This was not something I was looking forward to, mainly because I was working blind without the benefit of instructions or experience.

Back at the start of this thread, you'll have seen the photos of the cast springs and keeper plates. They were obviously meant to fit together in some fashion using the cast loops, but I couldn't immediately imagine how. Several trial fittings ensued, and I even entertained the thought of removing the keeper plate loop entirely. Of course, there still followed the question of how to fix the things to the frames, a job that seemed to require at least four pairs of hands.

Before all that, I recalled OzzyO's warning about the suspension spring bolt holes on the hornguides. I drilled them through, soldered in 1.5mm tube, carefully drilled clearance and then tapped 12BA. So far so good. All the bolts were trimmed down to around a third of their length, sufficient to have at least a millimetre projecting into the hornguide, so at least there was something for the spring to rest on while I wrestled with bearings and spring castings.

Each spring and keeper plate was assembled with a length of 0.9mm brass wire, filed flat and bent at right angles, passed through the loops and soldered to the central spring shackle. I forgot to take a photo. :oops: This left the keeper plate swinging on this "hinge". I tinned the mating parts where the springs were to fit the frames, and prayed to the gods of solder that this joint would be sufficient to hold things together while the loco is played with by its new owner.

Using an axle with one wheel fitted, with the square end through the bearing I was trying to fit and the wheel up against the opposite frame, then clamped up so the bearing was fixed against the spring and bolt, I eventually managed to wrangle the spring/keeper plate castings into place. More clamps, some flux and soldering iron, and everything seemed to fit in place neatly. The keeper plates are not fixed, held only by the wire "hinge". I have no idea if this is the way they are meant to be used, but having no instructions to speak of...

I repeated with the three remaining under-spring castings.

IMG_7504.jpg

The cab end springs are above the axle, so I had to, ahem, bodge the keeper plates. They are soldered directly to the bottom of the hornguides.

Now, I guess I don't need to actually spring the rear axle, as it's the driven axle. It has springing, nevertheless, as it made sense to me not to fix an axle at a riding height at this stage until I can ascertain exactly what that height will be. This I plan to do by using the brake hangers and adjusting things until it all runs level. Then, the plan says, I shall find a means of fixing the driven axle bearings so they don't move about.

You can tell I'm tending to wing things a bit. Still, refitting the coupling rods and everything still rolled. I shall fit the motor next and see if things can run under power.
 

Steph Dale

Western Thunderer
Heather,
If you're using springing I strongly suggest springing all axles of an 0-6-0, otherwise it somewhat defeats the object of the exercise!
Take care when mounting the motor to allow a small amount of rock and you should be away.
Steph
 

Heather Kay

Western Thunderer
Cheers Steph. That's kind of what I was thinking, but Best Beloved seemed to think otherwise. I am happy to have all sprung axles.
 

Heather Kay

Western Thunderer
Here's a shot that I hope shows how I arranged the keeper plate fitting with the spring casting.

IMG_7505.jpg

The keeper plate is joined to the spring casting with a short length of 0.9mm brass wire through the loops. The wire is bent at right angles, and filed to a flat on the mating surface, tinned and soldered to the spring centre shackle. (Not sure of the correct terminology of the parts, so apologies.) I dressed things off a bit with the file to make it a little less conspicuous.

In the set-up, the keeper plate is not actually fixed to the hornguides. The only fixing is the two spring hangers soldered to the frames. I have fingers crossed.
 

Steph Dale

Western Thunderer
Heather,
You should be fine with that, it's an approach I've used a couple of times in the past.
You can dven beef it up a little if you want to. In reality the retainer has a large hole in the middle of it, through which there's a bar connecting the hornblock to the spring strap, that bar well be much larger than a piece of 0.9mm wire will represent.
Steph
 

Heather Kay

Western Thunderer
You know I am not a GW modeller by nature. I researched this loco as best I could, with the help of Mr Beare of this parish. There's something that's been worrying me a little, though.

All the preserved pannier tank locos have that characteristic top feed casing in front of the dome. I am led to believe this is a fitting that was added to the locos in service from 1943. Since I'm building 7752 in virtually as-built condition to suit the early 1930s, I plan to leave off the top feed, and associated pipework, which you can see in this nearly-top-down shot of the actual loco:

3669152153_038594131e.jpg
DSC_7444 by Nick's Railways, on Flickr

I have no images of 57xx locos prior to the Second World War. I would like to check (a) the top feed and pipework on the tank tops was definitely a mostly post-war modification, and (b) that the remaining pipework on and around the footplate was as-built.

All help gratefully received. :thumbs:
 

Steph Dale

Western Thunderer
Heather,
Your chosen loco was ex-LT so watch out for changes to the gutters and cab roof eaves as well as trip cock brackets if you're using preservation-era pictures in your research.
Steph
 

Dog Star

Western Thunderer
I would like to check (a) the top feed and pipework on the tank tops was definitely a mostly post-war modification...
I have provided Heather with an extract from a GWR frame plane which shows the clack box as fitted to the boiler backplate of the panniers built in the 1920s and 1930s - Heather is now playing the JLTRT game known as "find the casting". The dwg is a cross-section with a dwg number circa 1930 and can be found in GWRJ issue no. 8.
 

Heather Kay

Western Thunderer
I just want to thank the Basingstoke branch of the Swindon Research Centre for their invaluable help in identifying what I needed to know. The ironic thing is the kit instructions show the boiler backplate clacks, without making any reference to them being superfluous if you build with the boiler top feed…

Right, back to hacking about the frames to fit the motor and gearbox. :thumbs:
 

Heather Kay

Western Thunderer
Heather,
Your chosen loco was ex-LT so watch out for changes to the gutters and cab roof eaves as well as trip cock brackets if you're using preservation-era pictures in your research.
Steph


Good points. I'm working with images of L94 (formerly 7752) and 5764 in preservation as my guide. The only obvious difference I've spotted so far is a kink in the pipe that runs along the valance on the fireman's side, which only occurs on L94/7752 and doesn't seem to be on 5764. Both are ex-LT locos, it seems.
 
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Heather Kay

Western Thunderer
I mentioned earlier that Graham has been enormously helpful tracking down some of the details for this build. For those that want to know, the rabbit hole that led to identifying the backplate clacks, and confirming that the loco being built did not have a top feed ahead of the dome at the period being modelled led Graham to the GWR Journal No8 of Autumn 1993, and an article on 57s at Reading.

Today I planned to fit the brake gear in such a way that it can be removed for painting and so on, and to fit the sandboxes. I got as far as cleaning up the sandbox castings, when I was diverted into fitting the bottom of the firebox and ensuring the motor/gearbox fitted properly.

Some cussing and much hacking with whizzy disc later, and things seem to fit well enough. The sandboxes and brake gear will have to wait for another day.

IMG_7517.jpg

For some reason I was originally going to fit the motor/gearbox unit so the motor was horizontal. Mulling things over, as one does, it became obvious the unit would fit much more tidily with the motor vertical. One of my increasingly common :rolleyes: moments. Some of the central spacer has had to be sacrificed, but this is much neater - and, crucially, means much of the gearbox is no longer in the cab. :D

IMG_7518.jpg

With the motor lifted away, you can see the bottom of the firebox has been fitted. This needed a little surgery in order to clear the spring castings at the front, and in order to clear the main drive gear and gearbox frame at the rear.

IMG_7520.jpg

Surgery to the rear of the firebox bottom. As ever, the brass etch here differs from that drawn in the instructions. I'm wearing a patch through scratching my head over this. Thoughts turn to arranging pickups now. Or sandboxes and brake gear. Or not. :confused: One day, I can get to the pretty bits above footplate level!

As predicted by others, there is precious little space in the frames for any speaker and DCC circuitry. There may well be a suitable speaker that will fit in front of the firebox between the frames, and the DCC gubbins ought to fit anywhere there's a space, but I've suggested to the client he has a think about whether he really wants the loco to be sound and DCC fitted at all.
 

3 LINK

Western Thunderer
Evening Heather,

Have you tried threading the axles through the hornblocks yet? Only it looks like you have the same hornblocks/guides that I had on my one, and because they are so " chunky " the axle ends do not protrude enough to fit both wheels flush let alone give any side play.

I do not want to pooh-pooh the build because you are doing a great job, and hopefully you won't have the same problem that I had :thumbs:.

Martyn.

P.S. I fitted my motor vertical and the gearbox was nowhere near the cab.
 

alcazar

Guest
That shot of the motor gearbox in place looks more like model engineering than straight modelling.

Is it an ABC unit?
 

alcazar

Guest
I like the new Slaters motor/gearbox combinations.

ABC are very good too, and the ex-Ron Chaplin ones are available via MSC....at a good discount for some society members.

Both of the last two have a very wide range of motor choice too.
 
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