East Barnet Joint Stock - a workbench

[Chas Levin]

2 hours ago, Jol Wilkinson said:

Chas,

 

I should have added that the centre axle(s) are set so that the bearings can rise when the outer axles are "bottomed out". That provides flexibility in the system to deal with track variation. Provided the track is built to a good standard, this should work as there shouldn't be much more than +/- variation over the loco wheelbase.

Coil springs have never really worked in 4mm, getting consistent miniature springs, calculating axle loads, etc. being difficult. CSBs address this better and wire springs  from music wire has proved better. However, despite the claims for CSBs I have stuck with compensation which is simpler to set up.

 

 

I have shortened Mashima motor shafts be wrapping the motor in masking tape, leaving just the shafts sticking out (to keep rubbish out of the motor and bearings). I then put the required end shaft in a micro drill, spin it up and use a good quality triangular needle file to "machine" a groove in the unwanted shaft. I take my time with this and don't apply too much pressure. When about 70% - 80% in and through the outer case hardening, the shaft can be broken off. Brush rubbish off and remove the masking tape. I've done that on about fifteen motors without problems.

Thanks Jol; the additional points about the Exactoscale system are very helpful and make perfect sense.

 

The mashima shaft shortening technique is excellent: I wish I'd thought of that and I'll certainly try it next time!

 

And yes, now I know from trying it how easy compensation is, and from reading about it how difficult springing can be, I suspect that in the long run I'll come to agree with you wholeheartedly but I'm actually very much looking forward to having a go at coil springing and CSB on other locos, just for the challenge of seeing whether I can make them work and for what I imagine will be my delight if I do, in seeing something so intricate and delicate actually working. Or not... .

 

After this build though, I'll relax with a wagon or coach or two, before the next loco!

Edited January 22, 2021 by Chas Levin

[Jon4470]

5 hours ago, Chas Levin said:

Jon, I meant to ask: how do you get the first notch going, to start the cut, without the blade slipping around? I tried my piercing saw on another piece of rod as an experiment last night but the springiness of the blade (even when tightened as fully as possible) contributed to the tendency to slide around on the extremely smooth metal surface and I had the greatest difficulty!

 

Chas

 

For the steel rods in a High Level gearbox I grip the rod in a vice. I then draw the piercing saw towards me with the blade up against the end of the vice ( as a guide and also meaning it can only slip in ondirection). Only try to saw once there’s is a groove in the rod. Oh....the part of the rod that you want to keep should be in the vice.....saves scrabbling on the floor looking for it

 

For motors I do what you did, I think. Grip the shaft with pliers close to the motor body. This also acts as a heat sink. Cut using a carborundum disc. Take your time and don’t force the disc.

 

Jon

[Chas Levin]

6 hours ago, Jon4470 said:

Chas

 

For the steel rods in a High Level gearbox I grip the rod in a vice. I then draw the piercing saw towards me with the blade up against the end of the vice ( as a guide and also meaning it can only slip in ondirection). Only try to saw once there’s is a groove in the rod. Oh....the part of the rod that you want to keep should be in the vice.....saves scrabbling on the floor looking for it

 

For motors I do what you did, I think. Grip the shaft with pliers close to the motor body. This also acts as a heat sink. Cut using a carborundum disc. Take your time and don’t force the disc.

 

Jon

Thanks Jon - I might try that next time, though I think I'm now a Cutter Convert.

 

For motor shafts, did you see Jol's post about rotating the motor shaft in a drill chuck and holding a triangle file against it? I think that sounds an excellent idea because it ought to reduce the possibility of damage to the motor...

[Chas Levin]

Things are getting exciting now:

 

Everything above the footplate is only posed or taped, as I start adding some lead weighting - nothing too excessive: a semi-circle about 3/4" wide inside the front of the boiler / smokebox, two pieces about 1 1/14" by 1/2", one inside each side tank and a curved fillet inside the bunker, about 45g in all. The centre of gravity is just aft of the front driving axle (about midway between the axle and wheel rim), which is where it needs to be according to my calculations, so the weight's being added in such a way that the COG doesn't move significantly, with running tests planned over the weekend before anything's fixed in place.

This job  - the weighting - was the reason I left the superstructure in sections: in order to solder the bunker sides and back from the inside, it has to go on before the cab fold-up, but experimenting with weights - and fixing them in place - is much more awkward with it on. And I think adding weight inside the tanks and boiler will likewise be easier before assembly...

A very elegant loco to my eye, even at this rather incomplete stage .

Edited May 9, 2022 by Chas Levin

[Jon4470]

15 hours ago, Chas Levin said:

Thanks Jon - I might try that next time, though I think I'm now a Cutter Convert.

 

For motor shafts, did you see Jol's post about rotating the motor shaft in a drill chuck and holding a triangle file against it? I think that sounds an excellent idea because it ought to reduce the possibility of damage to the motor...

 

I saw Jol’s post. Looks like a very good method and I’ll give that a try next time.

 

Jon

[Chas Levin]

Lead  taped in position in the boiler and sidetanks for test-running, and bolted to the bunker floor:

 

I realised of course that soldering would not be good for longterm araldite stability! So, the piece in the bunker is held in place by two 14BA bolts going down to nuts under the footplate (which I'll threadlock and trim down later on) and the pieces inside the boiler and side tanks I also realised can be inserted from the underside of the body, after those assemblies have been soldered in place - not sure why I didn't spot that earlier on, but there we go!

The rather unattractive curved cutouts in the footplate to allow crankpin clearance will of course be hidden inside the side tanks .

I spent today test running, and wrestling with the pickups. My previous build was a rigid chassis and simple 0.3mm PB wire works very well on it, with only occasional tweaks needed. Here however, the extra movement of the front drivers' axle - vertical, lateral and angled rocking - is proving a little more of a challenge. In curves in particular, performance is not quite as reliable as I want, though it's perfect on the straights. The pickups are bearing on the rear edges of the four drivers, but I might try them on the wheel backs to see if that improves things...

The other area in which I'm still not happy is bogie spring guidance. With the central guide spring engaging its footplate bracket (the spring is soldered to the front top edge of the bogie and engages a bracket about 8mm long, made of scrap etch, under the front of the footplate, just behind the buffer beam) the front wheels of the bogie have a tendency to lift slightly on curves and are more prone to derail coming out of or going into points. With the guide spring disengaged and the bogie controlled only by the weight of the compensating beam, it track more reliably but the bogie is then not imparting any guidance to the body.

Clearly some more thought is required: possibly a broader rubbing plate extension for the front of the bogie stretcher, to distribute some of the compensating beam's downwards force to the sides of the bogie, thereby discouraging the wheels from lifting...?

One thing that makes it very difficult to assess what's needed is the inconsistency of the problem. The loco in its current form will happily negotiate several circuits with no faults, but then persistently derail or foul a frog several times in a row. In spite of doing my best to examine the exact state of things at the moment of the fault, it's very difficult to see what's happening. The act of lifting the loco destroys the precise alignment of components that might give a clue as to what's going on, but there's only limited information available from a top-down view, even with nothing on the footplate aside from the boiler and cab fold-up.

I've so far resisted lubrication as it's still pre-painting and I prefer to keep anything like that well away until after that's been done, but I may give in and resign myself to long and careful degreasing later on, because I'm wondering whether some at any rate of the problems are down to the fact that various parts of the drive train and compensation mech that need to be able to slide and move very freely and easily - especially in and out of curves - are too dry to do so .

It runs so beautifully on my straight test track, where things don't need to move around as much...

Edited May 9, 2022 by Chas Levin

[Chas Levin]

I decided last night that I was getting far too preoccupied with chassis tweaking and losing sight of the big picture, so it was out with the soldering iron at 7 o'clock this morning and the coal bunker, balance pipes, steam chest and side tanks are now here to stay:

 

It also occurred to me that rather than messing about aralditing lead weights at a later stage, I could solder them inside the tanks and boiler - as you see in the photo above.

Leaving the cab fold-up until last meant I could solder the bunker from the inside, with predictably neater results and likewise the side tanks (though getting in under the bottom edge of the lead was a challenge!).

Some cleaning up to do tomorrow, and some attention needed to a tiny but irritating discrepancy between bunker and side tank heights, but generally a good result.

Good to get the iron fired up again!

 

Edited May 9, 2022 by Chas Levin

[Chas Levin]

Another early morning soldering session and the cab fold-up's in place (with the roof perched on top for effect):

 

Soldering the cab fold-up with the bunker in place was a little more difficult than if it had been done the other way round as in the instructions, but being able to solder the bunker from the inside was worth it. I also checked and I should be able to reach up inside the body to solder the tank tops from the inside too - another very visible area that will look way better done that way...

 

I also found time to pop some coal on a Hornby A4 tender - this is from a vintage Seagull, but has had the tender motor unit removed (and replaced with weighting) and the body modified to run on a loco drive unit from the more recent Falcon:

 

Even without any other modifications or, adding real coal makes a huge difference (almost as huge as some of those lumps of coal, now I look at the photo rather larger than life!).

Edited May 9, 2022 by Chas Levin

[Chas Levin]

Boiler fittings cleaned up and fettled and settled - only posed here:

 

I'm using the Ramsbottom safety valves rather than the Ross Pop as that was standard until 1925, which involved a lot more work than would have been needed for the Ross Pop. The boiler comes pre-drilled for the two Ross Pop (which fit very easily and quickly, should they be used) necessitating opening out one of the holes to accommodate the Ramsbottom casting and the slight backward lengthening. It also needed some quite awkward removal of material form the underside of the valve casting to allow it to sit properly; it's small - and delicate in part - for holding sufficiently steadily to allow removal of the cast brass, which is very hard material. I also had to remove the central section of the boiler band, which I'd put on before realising which valve type I'd need to use. The chimney - a tall plane one, as fitted to the first ten C12s - and the dome required only the most minimal work though in terms of seating properly.

Both those fittings however had casting lines down each side and previously I'd have laboured over them handheld too, but Jol W's post a while back about gripping a motor shaft in a drill and holding a file against it set me thinking about other ways of moving the workpiece rather than the tool (second nature to lathe users I expect...) so as both fittings came with long spiggots the job was accomplished much more quickly and easily.

For fixing them, I'm going to try a method I saw on a Tony Wright video, tinning both boiler and fitting underside with 145 degree, then joining with 70. I wouldn't have thought of this, where both pieces to be joined are brass, but it sounds an excellent idea... That being said, Mr Belts and Braces here also intends leaving about 5mm of spiggot in place and, having broached out the locating hole in the boiler suitably, adding further security with araldite inside the boiler and round the spiggot. Probably a bit over the top, I hear murmured, but the way I'm figuring it, both araldite and a 70 degree solder joint are not always 100% reliable over a long time period and if there's one thing I don't want to see it's a detached chimney or dome .

 

Meanwhile, in other news, my somewhat vintage spring dividers suddenly divided, for the last time!

 

I was measuring a pretty small distance (from the top of a tank side to the scribed line along the inside) and I put the dividers to one side, under tension... a loud ping followed. I haven't yet found the other half of the spring .

A new one is now on order...

The reason I was measuring the distance of that scribed line along the upper inside of the tank is that the line is at a different height on one side tank to the other. The righthand tank has the line at a height that gives the correct alignment for the tank top, but the lefthand tank side's line is way lower. I'm guessing this is just a 'misprint' on the etch - not a big problem; happily i'd already scribed a replacement line before aged pieces of iron started flying round the room!

Edited May 9, 2022 by Chas Levin

[Jol Wilkinson]

Chas,

 

your workmanship is really neat and clean.

 

my approach with boiler fittings is to clean up any casting flash while holding the dome or w.h.y. by the casting sprue and then cut off most of the sprue with a piecing saw, finally removing the remaining stub with an abrasive wheel in an electric micro drill. I then wrap a piece of emery paper inside out around the boiler/smokebox and "file down" the underside of the casting by rubbing it along/around that to get a close fit.

 

It looks as though the C12 castings were a close fit already, which is good. LNWR chimneys with the thicker square base are the worst culprit.

 

Keep up the good work.

 

Jol

 

 

[Chas Levin]

Thanks Jol; I'm getting myself into the habit of doing a fairly full cleanup after every soldering session. It slightly cuts into actual soldering time, but it helps me see any faults or problems better. It also avoids those situations where you can't fully access something that needs cleaning up because of subsequent additions.

 

Thanks for the suggestion - in fact, I'd read of the 'inside-out emery paper round the boiler' technique in one of Iain Rice's books and if these items were spiggotless (that's a nice new word, isn't it?) I'd have done just that, but the opportunity to anchor a short spiggot in araldite is too tempting.

 

How do you usually fix cast brass boiler fittings to brass boilers?

 

I've spent quite a bit of time over the past couple of days fettling the tank tops, boiler and cab roof. The combined fit of them all affect each other and the sit of the boiler and of the cab roof are - literally - very high profile features. I'm currently getting a somewhat wider gap between the inner edges of the tank tops and the boiler sides, which puzzles me somewhat as the tank sides are accurately soldered in the locating grooves that run along the footplate. Worst case scenario that gap can be filled with solder, though it will then require quite a bit of work to make it appear like a natural continuation of the brass tank tops.

 

Possibly a thin strip of brass in the gap, with another underneath to join it to the main tank top: sweating the joiing piece to the upper two pieces would run solder into the seam between the original tank top and the filler piece, and the result could them be smoothed and finished invisibly...We'll see - it may be that some more adjustment may close the gap sufficiently.

 

The accuracy at this stage is particularly important as I'm going to leave the cab roof separate until after painting and crewing, so it'll have to be glued - not keen on this at all as I'd prefer soldering, but the cab detail is worth the compromise I think. Therefore, gaps - even miniscule - between cab roof and body can't be filled with solder...

 

 

[Jol Wilkinson]

Hello Chas,

 

I use araldite too, the area of the casting giving a good bond and any excess is pushed out of the locating hole. I draw  fine pencil lines to show the lateral and longitudinal locations of the fittings, although a line of sight view along the boiler is the final measure.

 

Getting the etches for the fit of the tank fronts or to the boiler is one of the more difficult bits of etched kit design. Fortunately the LNWR didn't bother, leaving the rectangular tank outline obvious. Not so with the cab side with square splasher front which was matched up to the firebox sides, which has given me problems on several kit designs. If the loco is finished in black and you get a fairly close fit, the gap shouldn't be too obvious. This picture show the unpainted second test build for a LNWR Jubilee and the gap, which appears, isn't so obvious on a the pained version of the production kit.

 

 

 

 

 

 

 

[Chas Levin]

Thank you for posting the pictures - that's a very handsome loco, isn't it? You're right that when it's painted black the gaps disappear... in the case of this C12 however, I've 90% made up my mind to do it in GNR livery .

 

I'll spend some more time with it tomorrow evening and see what I can work out. I think the gaps along the tops and fronts of the tanks will have to be filled somehow though, as it will be far more noticeable in green.

 

By the way, one of the things that made the GNR livery seem more achievable, given my less than expert painting and lining skills, was your mention on Tony Wright's thread of companies that will make up custom aerosols from a colour sample, which will allow me to spray the first green on, and in cellulose too: that should make the second colour and the lining easier to get right (and correct if - when - I make mistakes). I had no idea that was a service anyone offered!

 

Edit: just looking at those pictures again, is the painted one the same actual model as the unpainted test build? Somehow the superstructure looks slightly lower - or a little more squat - on the painted one. I'm wondering whether it's a trick effect from the different colours, the way the eye is drawn to the detail of the bare brass, as against the more monolithic appearance of the finished one, or whether there is actually a difference...? Or it may be my imagination of course - it's a very fine difference. I'll look at it again tomorrow after a good night's sleep .

Edited January 31, 2021 by Chas Levin

[Jol Wilkinson]

Did the tanks actually butt up against the boiler cladding? The boiler and firebox were subject to expansion and contraction. The top of the tanks on LNWR locos was close to the boiler but wasn't actually joined to it. This picture of a LNWR 4' 6" 2-4-2T gives an idea. Some other LNWR tank locos had visible brackets rivetted to the tank top that passed through the cladding and were rivetted to the boiler to locate the tank. If used on the 4' 6" Tank, they aren't visible as far as I could find.

 

 

 

The unpainted Jubilee was the second and final test etch build, the painted one from a production kit. There wer e only a few very minor changes, so they are in effect the same. It was my first etched loco kit design from which I learned a lot.

 

The black paint is several coats of airbrushed cellulose. It give a smooth gloss finish, ideal for waterslide transfers. A final coat of Ronseal varnish with a small amount of black protects the transfers. That is as recommended by Ian Rathbone in his excellent book.

[Chas Levin]

Thanks Jol, that's very interesting. Of course it makes total sense that there would need to be room for expansion and contraction; I hadn't thought of that at all.

I'd assumed that the tanks would be joined to the boiler partly from looking at photos of others' models. In most cases that I've seen so far they're either clearly soldered - in unpainted examples - or any gap has been eliminated from visibility on the finished model and again in many cases, it's very clear that the gap has actually been filled, though whether by solder, filler, primer, paint or a combination of those isn't clear. In still other cases, such as your picture of the Jubilee, the gap has become invisible in photos after painting, though examination of the model in person might show it still present. Also, I'd not spotted the expansion gaps in prototype photos - I shall go back and take a closer look at some this evening.

The gap between tank and boiler in that LNWR 4'6" 2-4-2T (another very fine looking loco!) looks so narrow though, that I'd have assumed it would disappear completely after priming and painting as those materials would end up filling it, even if applied in very thin coats - is/was that the case, or is that in fact a recent photo of a build that remains unpainted?

 

Also an interesting point about tank-to-boiler rivetted brackets: there are none in this C12 kit and none visible on the Isinglass drawings. There are tank/footplate brackets though, which aren't visible on the drawings either, though I'm hoping some study of prototype photos will explain those.

 

I thought it would be the case that even though your painted Jubilee photo isn't the same physical item as the test build, there should be no difference between them. I think this may be an example of the way an object is coloured - and the way its surface is finished - influence the visual appearance of its shape. I've looked again, but of course I'm now in that position where I cannot stop seeing the difference, having once seen it. Is it perhaps a little like the way people are sometimes advised to wear black because its slimming? (I mean that as a serious question, not as a joke, though I clarified with my wife that black clothing is recommended for that purpose and she found it funny that I was asking because of perceived differences between model locos...).

 

I thought also about what you said a couple of posts back about how "getting the etches for the fit of the tank fronts or to the boiler is one of the more difficult bits of etched kit design". Like many end user kit builders, while I often marvel at the ingenuity of kit design (the tank top-plus-inner cab sides fold-ups in this C12 being an excellent example) I don't often stop to consider how easy or difficult designing such pieces might be but once you'd said it I realised that this must certainly be a complex area. Rather easier in the world of white metal...

 

And  regarding painting, I just bought Ian Rathbone's book a few weeks ago, read it from cover to cover and now have it standing by for the next paint job (which will be this C12, aside from a quickie plastic kit that's also brewing). Absolutely fascinating and full of extremely useful techniques and advice - that and the short films he's made, which another poster had directed me to a while back, are a pretty comprehensive course in the subject.

[Compound2632]

47 minutes ago, Chas Levin said:

Thanks Jol, that's very interesting. Of course it makes total sense that there would need to be room for expansion and contraction; I hadn't thought of that at all.

I'd assumed that the tanks would be joined to the boiler partly from looking at photos of others' models. In most cases that I've seen so far they're either clearly soldered - in unpainted examples - or any gap has been eliminated from visibility on the finished model and again in many cases, it's very clear that the gap has actually been filled, though whether by solder, filler, primer, paint or a combination of those isn't clear. In still other cases, such as your picture of the Jubilee, the gap has become invisible in photos after painting, though examination of the model in person might show it still present. Also, I'd not spotted the expansion gaps in prototype photos - I shall go back and take a closer look at some this evening.

The gap between tank and boiler in that LNWR 4'6" 2-4-2T (another very fine looking loco!) looks so narrow though, that I'd have assumed it would disappear completely after priming and painting as those materials would end up filling it, even if applied in very thin coats - is/was that the case, or is that in fact a recent photo of a build that remains unpainted?

 

I wonder if, as modellers, we're subconsciously influenced by the injection-moulded body of that Triang Jinty or whatever we started out with. I don't think I've ever seen the inside walls of the tanks modelled! In 00, they would inevitably foul the wheels. Even in P4 I suspect one would have to model the invisible splashers correctly to get the clearance.

[Daddyman]

2 hours ago, Compound2632 said:

 

I wonder if, as modellers, we're subconsciously influenced by the injection-moulded body of that Triang Jinty or whatever we started out with. I don't think I've ever seen the inside walls of the tanks modelled! In 00, they would inevitably foul the wheels. Even in P4 I suspect one would have to model the invisible splashers correctly to get the clearance.

Tank inner walls are supplied on all the Connoisseur kits I've built. Ditto 52F's C15 and C16 - including the curved apertures to avoid the wheels in the latter two cases (whether for 00 or P4).  

[Jol Wilkinson]

Designing an etched kit to cope with the differences in 4mm scale gauges causes complications.  Variation in wheel B2B requires different frame, bogie and truck spacers, different cab wheel splashers and footplates, boiler cutouts for 00/EM driving wheels. Deeper flanges for 00/EM mean oversize splashers, although recommending using a slightly undersize wheel to represent worn tyres is possible. White metal kit manufacturers generally haven't provided these options, but may have had to make allowances for thicker walled items such as in splashers. I think that dates back to w/m kits being produced form a period when RTR models weren't so well detailed and only available in relatively few prototypes. Etched kits rather changed that, as the designers didn't have to own the production equipment and so anyone with a large drawing board, access to plans drawings and a desire to produce something new/better could do so. A bit like 3D design and printing now. The thing is to know what to etch/print and when to use other materials/media to get the best product. 

 

Getting the amount of detail right is also a bit of a challenge. Clearly superstructures need to be pretty much correctly detailed but how much undercarriage detail should you add? Brake shoes and pull-rods, sandboxes and sandpipes and other clearly visible stuff should be provided but is all the barely visible brake gear worth adding if it needs a variety of optional gauge parts and can barely be seen when on the track? Sometimes it has to be omitted to fit the recommend or available motor/drive trains. It can be argued that the builder has the option to leave off what he doesn't want to use, but as a designer you get to wondering when to stop adding the fine detail (unless your name is Dave Bradwell, Martin Finney or Brassmasters). However, you can end up with kits that then carry the "too difficult for many modellers" reputation. I am always aware that, when designing a kit for John at London Road Models, it has to be suitable for all three 4mm gauges and a spread of builder experience, so straightforward to build as well as accurate and detailed.

 

Interesting the David points out that Connoisseur and 52F provide inner tank walls. I hadn't encountered that before in 4mm kits and I find that having ready internal access to the tank proves a good place to fit sheet lead for ballast.

[Chas Levin]

On 01/02/2021 at 14:02, Compound2632 said:

 

I wonder if, as modellers, we're subconsciously influenced by the injection-moulded body of that Triang Jinty or whatever we started out with. I don't think I've ever seen the inside walls of the tanks modelled! In 00, they would inevitably foul the wheels. Even in P4 I suspect one would have to model the invisible splashers correctly to get the clearance.

I'm sure that's true! As I said in an earlier post, I hadn't realised there was a gap at all, and as a relative newcomer to kitbuilt locos my knowledge would certainly have been conditioned by RTR. I took a look at some of my vintage 60s to 80s RTR today and there are predictably no gaps. However, things have been improving - here's a pair of Bachmann J72, one is from when the first model was around, one from the recent reissue:

 

 

I must admit I hadn't even noticed the difference until now, though I hadn't sat and compared them.

I also looked for some prototype photos that showed the gaps between side tanks and boilers, but it's not as easy as I'd thought. I hadn't stopped to consider, for one thing, what a relatively small proportion of locos actually had sidetanks, in amongst all the Atlantics, Pacifics, Moguls and the rest! I found a few, but so far only showing the vertical front tank faces - photos taken from above seem less common:

 

 

 

 

I thought this one was rather interesting: it looks to me as if there's quite a wide gap, which has a sort of concave canopy bridging it - a rainwater channel, perhaps?

 

 

(May 2022 - going through posts to replace photos lost when RMWeb went down earlier this year and had to change host company, I hav found some where I didn't keep the photos...)

Edited May 9, 2022 by Chas Levin

[Chas Levin]

4 hours ago, Daddyman said:

Tank inner walls are supplied on all the Connoisseur kits I've built. Ditto 52F's C15 and C16 - including the curved apertures to avoid the wheels in the latter two cases (whether for 00 or P4).  

That's interesting: I'd been thinking of trying a 52F kit in due course...

[Chas Levin]

4 hours ago, Jol Wilkinson said:

Designing an etched kit to cope with the differences in 4mm scale gauges causes complications.  Variation in wheel B2B requires different frame, bogie and truck spacers, different cab wheel splashers and footplates, boiler cutouts for 00/EM driving wheels. Deeper flanges for 00/EM mean oversize splashers, although recommending using a slightly undersize wheel to represent worn tyres is possible. White metal kit manufacturers generally haven't provided these options, but may have had to make allowances for thicker walled items such as in splashers. I think that dates back to w/m kits being produced form a period when RTR models weren't so well detailed and only available in relatively few prototypes. Etched kits rather changed that, as the designers didn't have to own the production equipment and so anyone with a large drawing board, access to plans drawings and a desire to produce something new/better could do so. A bit like 3D design and printing now. The thing is to know what to etch/print and when to use other materials/media to get the best product.

Very interesting Jol, thank you for putting down your thoughts. I'd noticed the multi-gauge aspect with great interest in building this C12. My previous loco build was a DJH w/m J9/10, where there was no provision for alternative gauges, so although I'm working in OO I was impressed by the ingenuity of the provision for the other sizes. And although I haven't built many locos yet, I've noticed some interesting variations in various other etched kits between items some kits supply etched and some cast. I also took a look through some of the unbuilt kits in my pile and there are clearly lots of opinions on which materials to use...

 

4 hours ago, Jol Wilkinson said:

Getting the amount of detail right is also a bit of a challenge. Clearly superstructures need to be pretty much correctly detailed but how much undercarriage detail should you add? Brake shoes and pull-rods, sandboxes and sandpipes and other clearly visible stuff should be provided but is all the barely visible brake gear worth adding if it needs a variety of optional gauge parts and can barely be seen when on the track? Sometimes it has to be omitted to fit the recommend or available motor/drive trains. It can be argued that the builder has the option to leave off what he doesn't want to use, but as a designer you get to wondering when to stop adding the fine detail (unless your name is Dave Bradwell, Martin Finney or Brassmasters). However, you can end up with kits that then carry the "too difficult for many modellers" reputation. I am always aware that, when designing a kit for John at London Road Models, it has to be suitable for all three 4mm gauges and a spread of builder experience, so straightforward to build as well as accurate and detailed.

 

I think you were in on the recent discussion on Tony Wright's thread about why we pursue different levels of detail? Personally, I welcome it all, as I'd want to incorporate anything I can. I'd also have thought that others can leave off anything they don't want to include, but I can also see that many will feel pressured to use things that the kit has included and I have indeed seen reference to near unattainable Finney-esque detail levels rendering a kit unsuitable for many!

 

This is another are like what we were discussing earlier about the designing of difficult areas like tank top and boiler interfaces, where I hadn't stopped to think about how it must be for the designer, assessing how much detail to include, and balancing the needs of advanced and accomplished builders.

 

This C12 build would have been far quicker and more straightforward if I hadn't also been embarking on my first compensated build, which meant I spent a lot of time reading about how that worked and considering springing too, before deciding to postpone that for a later project.

 

4 hours ago, Jol Wilkinson said:

Interesting the David points out that Connoisseur and 52F provide inner tank walls. I hadn't encountered that before in 4mm kits and I find that having ready internal access to the tank proves a good place to fit sheet lead for ballast.

 

Indeed - as is the case with the C12. I wonder though whether it's still possible to slide thin lead up into the tank cavities, between the inner and outer tank walls?

[Compound2632]

41 minutes ago, Chas Levin said:

I thought this one was rather interesting: it looks to me as if there's quite a wide gap, which has a sort of concave canopy bridging it - a rainwater channel, perhaps?

 

I think it's not unusual for there to have been a "modesty panel" covering the gap between tank top and boiler/firebox cladding, or for the cladding to curve round to sit on the tank top (Midland engines). When filling the tanks at a water column, this would stop the overflow from running down the gap between tank and boiler.

[Chas Levin]

So, first thing this morning I got cracking with the tank tops. Hving spent too much time already trying to assess how they and the boiler would fit, whilst preserving the critical fit and alignment of the cab roof, there was no getting away from the fact that those tank tops would have to go on first!

I was determined not to mess up the ultimate alignment of the cab roof however, so I devised a way - by means of some cardbaord shims and small pieces of wood - of tack soldering the tank tops in place whilst holding the cab roof in its slots at the same time and here's the result:

 

And seen here with the cab roof sat on top: there's still a little fettling to do, but considering that the roof is just sitting in place, I'm fairly pleased with the general state so far:

 

However, the gaps down the sides of the boiler do look a little wide to me. Having learnt in the course of the last couple of days that there are actually meant to be gaps, I have yet to see any that are quite this wide - please excuse the number of photos, but I wanted to show it from several angles. It looks acceptable to me from eye level or from the side, it's when you look down from above that it doesn't look quite right. The boiler's only sat in place at the moment and it sits ever so slightly to one side - easily correctable when it comes to permanent fixing, so that aspect can be safely ignored, but can anyone advise whether this width gap is reasonable please?

 

 

 

Edited May 9, 2022 by Chas Levin

[Chas Levin]

11 minutes ago, Compound2632 said:

 

I think it's not unusual for there to have been a "modesty panel" covering the gap between tank top and boiler/firebox cladding, or for the cladding to curve round to sit on the tank top (Midland engines). When filling the tanks at a water column, this would stop the overflow from running down the gap between tank and boiler.

Aha, thank you - this might perhaps solve the gap problem I just posted about - but did the GNR ever employ that sort of thing I wonder? Something to investigate tomorrow...

[Daddyman]

This is a Caley 439 obligingly lying on its side at Balnaguard, showing how the boiler clothing curves to meet the tank tops. Took me years to find a clear photo of this, and I'll be another few years working out how to model it.... (I've never seen it modelled on 439s, or other Caley locos that had this feature.) 

 

Re lead, I think the plan is you put it in there before closing the box up on the Connoisseur models. With 52F models it's different, as the tanks are full of support webbing. 

 

Edited February 2, 2021 by Daddyman