Socially Distanced Challenge – CR Class 488 Build

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David Knight
Posts: 662
Joined: Sun Jul 20, 2008 6:02 pm

Re: Socially Distanced Challenge – CR Class 488 Build

Postby David Knight » Thu May 28, 2020 5:05 pm

Le Corbusier wrote:
David Knight wrote:... your work ethic is inspirational :thumb :thumb


Shouldn't that be 'play' ethic :D for myself the moment it becomes work is the moment the hours appear to stall :thumb ... never really had much work ethic but miraculously still manage to churn out what is often called work :shock:


Interesting. I’ve always classified it as Work and work. The capitalised Work is that which cannot be avoided. The lower case work is the type I embrace with some joy in my heart. I suspect that Lindsay approaches his modelling as work rather than Work. Regardless, he has done more in the past month than many will do in a year.

Cheers,

David

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Le Corbusier
Posts: 1512
Joined: Wed Feb 11, 2015 3:39 pm

Re: Socially Distanced Challenge – CR Class 488 Build

Postby Le Corbusier » Fri May 29, 2020 6:49 am

David Knight wrote:
Le Corbusier wrote:
David Knight wrote:... your work ethic is inspirational :thumb :thumb


Shouldn't that be 'play' ethic :D for myself the moment it becomes work is the moment the hours appear to stall :thumb ... never really had much work ethic but miraculously still manage to churn out what is often called work :shock:


Interesting. I’ve always classified it as Work and work. The capitalised Work is that which cannot be avoided. The lower case work is the type I embrace with some joy in my heart. I suspect that Lindsay approaches his modelling as work rather than Work. Regardless, he has done more in the past month than many will do in a year.

Cheers,

David

Just joshing! ..... All for defining something which i enjoy doing and resent not having time to get on with as 'work' :D though I will struggle to get my other half to see it in that light ... in that department the definition is most definately 'play' ;) which is in no way to denegrate the hours spent or impressive progress made by Lindsey .... even before we get on to the obvious high skill levels :thumb
Tim Lee

Lindsay G
Posts: 167
Joined: Thu Aug 07, 2008 2:16 am

Re: Socially Distanced Challenge – CR Class 488 Build

Postby Lindsay G » Fri May 29, 2020 9:39 am

Thanks all for the input and comments since the last update.

I think it has to be work, otherwise I'll have to redesignate my gloryhole a playshop. But I definitely play golf - but not well, perhaps I need to work at that.

I've never thought of trying to anneal castings. However, the downwards pipes on the injector pipework ares 0.8mm Albion Alloy brass tube (tube made assembly easier), so I thought I'd try annealing it to make shaping easier - got the gas soldering iron out, fitted the blowtorch nozzle, did the business, let it cool, and found it turned to dust between my fingers - perhaps annealing 0.1mm thick brass is a step too far, or I was too heavy handed.

And I'm definitely an obsessive detailer but not rivet counter which I'll perhaps prove somewhat when we get on to the chassis.

Lindsay

bécasse
Posts: 57
Joined: Sun Jun 17, 2018 8:26 am

Re: Socially Distanced Challenge – CR Class 488 Build

Postby bécasse » Fri May 29, 2020 11:19 am

Lindsay G wrote:Thanks all for the input and comments since the last update.

I think it has to be work, otherwise I'll have to redesignate my gloryhole a playshop. But I definitely play golf - but not well, perhaps I need to work at that.

I've never thought of trying to anneal castings. However, the downwards pipes on the injector pipework ares 0.8mm Albion Alloy brass tube (tube made assembly easier), so I thought I'd try annealing it to make shaping easier - got the gas soldering iron out, fitted the blowtorch nozzle, did the business, let it cool, and found it turned to dust between my fingers - perhaps annealing 0.1mm thick brass is a step too far, or I was too heavy handed.

And I'm definitely an obsessive detailer but not rivet counter which I'll perhaps prove somewhat when we get on to the chassis.

Lindsay

You can anneal small brass items, or short lengths of brass section, wire, strip or tube, using a candle (or similar) flame. It's much more controllable than a blow torch!

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Rod Cameron
Posts: 690
Joined: Fri Jul 25, 2008 12:01 pm

Re: Socially Distanced Challenge – CR Class 488 Build

Postby Rod Cameron » Fri May 29, 2020 10:37 pm

After an attempt to anneal some brass section in which it failed spectacularly, I was advised that because brass is an alloy the crystalline structure can disintegrate on the heating to red that you might apply to (say) copper or steel (which works because it's still mostly iron). So your part 'turning to dust' makes sense. Maybe bécasse's suggestion of just using a candle gets round it, but don't overheat it.
Rod

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Will L
Posts: 1783
Joined: Sun Jul 20, 2008 3:54 pm

Re: Socially Distanced Challenge – CR Class 488 Build

Postby Will L » Sat May 30, 2020 10:53 am

I too have noted that drilling cast brass bits can be a problem. Having had a good read round the internet, it seems that what is in "brass" is quite moveable feast. Silicon is added sometimes because it makes the the metal flow well and fill the mould, but results in a harder casting. Lead is also used as it improves machining and casting properties, but if you over heat cast brass with a lead it is apparently inclined to fall apart as you described. This is because the brass is quite crystalline. The lead tends to collect around the boundaries of the crystals and liquefies well before the other continuants.

Lindsay G
Posts: 167
Joined: Thu Aug 07, 2008 2:16 am

Detail Therapy – Chassis (part 1)

Postby Lindsay G » Mon Jun 01, 2020 3:37 pm

My original intention was to move from having the wheels turning with coupling rods attached to adding the outside cylinders, associated gubbins, and connecting rods. However, heavy-handed me might have tweaked the geometry of that when adding further detail to the chassis so decided to add detail before the motion.

Westinghouse Reservoir
This starts life as a short length of 6mm OD brass tube - luckily to hand, with thickness of tube reduced on the inside via a countersink bit. 2 discs of brass were cut/filed for the ends, drilled for the pipes, strung on a length of 5mm wire for the pipes separated by a spacer brass tube, then soldered into the tube. Riveted bands were made from 4 thou brass sheet with the rivets embossed using a needle in a pin vice and High Level CSB jig to space them consistently. The “bands” were cut with scissors and soldered onto the tube.


Chassis additions.jpg

The tank was then fitted via a small section of wire between it and the rear spacer and the pipes bent up and soldered out of sight on the chassis. It sits just beneath and behind the rear buffer beam so it’s rather in the way of an AJ coupling, time will tell if it remains in place!

Brakes
I wanted to make the brakes removable so that the wheels/gearbox/motor could be removed. The starting point was the addition of 0.6mm OD tubes to the chassis for the 4 brake levers and 0.5mm for the pivot bar beneath the cab. An overlay was made for the brake pivot bracket, rivetted, and soldered in place. Brake levers were made from thick N/S fret material doubled over at the bottom per the prototype with 0.3mm wire sandwiched in a groove between them, fettled to shape, then 0.4mm soldered at the top. Temporary brake blocks were fashioned from plasticard (final blocks yet to be made, and may be 3D printed as the shape of latter blocks fitted was rather complex), and attached via double-sided tape for fitting (they didn’t remain attached for too long!).

Pivots were made from fret material, drilled 3 times and wire fitted back and front to 2 of the holes, and the pivots fitted into the rear tube. The link rods to the pivot at the rear were part of the etch – for the period being modelled, such rods actually had 10 adjusting holes but I didn’t have any rods on brake etches to match that and I’ll never be able to create 10 neat holes, so I will live with rods from an earlier period. Rods connecting the front and rear pairs of blocks were not supplied with the etch so had to be manufactured. 0.5mm tubes were cut for the cross bars, everything threaded together, inserted in the tubes on the chassis and soldered together.

Sandpipes
These were made as an integral part of the removable brake assembly by soldering the lower end behind a brake block just in case the pipe was the possible source of a short if it was bent against a wheel. As with the brake levers, the sandpipes fit into a 0.6mm OD brass tube soldered across the chassis.

Firebox bottom and ashpan
Now this little item has really grown like Topsy, the finished item never being envisaged at the outset - not even when the first parts of it were soldered together! The firebox area was always planned being one part N/S sheet (to provide some depth away from the ashpan) overlaid with a .5mm sheet of brass with rivets embossed. On this occasion the rivets were freehand with a needle and a rule acting as straight edge and for (fairly) even spacing attempting to replicate the prototype pattern but not the number of rivets . The ashpan curved under at the bottom and I wanted to create the impression of this but was not sure how much of a curve I’d get before it restricted removal of the gearbox/motor. So the N/S sheet was cut overlength, curved to the envisaged diameter, and soldered to the firebox section, repeated for the other side, and the 2 sides soldered to a cross piece shaped accordingly for a trial fit. However, it turned out that there would be little of the curve left for clearance and it was going to look rather disappointing in appearance.

Thinking cap on. What if it weren’t cut for the gearbox, but was made as a removable unit that was fitted after the wheels were in place? But how to fit it as the gearbox precluded any fitting towards the front? There was the spacer that housed the bogie pivot. So, a further section of N/S was cut to fit between the 2 sides to make an integral unit (nothing too pretty underneath now but it will never be seen in service) and a bracket was made from a frame spacer reduced very slightly in width, cut to avoid the bogie pivot, soldered in place, and a 12ba bolt soldered to the spacer to secure it. The overlaid riveted bands on the ashpan were replaced as they looked a bit crude, rivets again marked using the CSB jig :


Ashpan unit.jpg

The final addition to the firebox/ashpan assembly will be sections of brass soldered to the inside which will prevent the CSB wire from escaping.

Springs
Cast items were bought at a show from Alan Gibson. They more or less looked like the springs needed but turned out to be way too wide. However, a quick snip with cutters to remove the centre area, a rough file to the remaining outer parts, some high degree solder, then more filing and we have the first of our four springs. Mightn’t look too pretty in its naked state but that isn’t a concern – some solder would later be removed to reveal leaf springs (at one end only).


Springs before and after.jpg

Positioning them correctly on the chassis took up a lot more time than expected involving having to shape the outer legs in several directions to solder them to the inside of the chassis, each taking a few goes to get the height, lateral position, and distance between splasher and boiler correct – and possibly because of a combination of metal and mental fatigue there were some casualties in the process. However, they’re all fitted, again not looking too pretty with little uniformity to the shape of the legs, but only a glimpse of the upper outer ends will be seen ultimately, and these areas appear fine. After some tweaking on the chassis (and tidying up behind) a cosmetic overlay was re-introduced to the top centre of each the springs, and we have the following chassis :


chassis rear.jpg

chassis front.jpg

All that remains now is the injectors, pick-ups, outside cylinders and motion, and some detailing around the cylinders - and that temporary frame spacer fitted at the front finally removed - but I’ll do some work on the footplate module before that.

Lindsay

P.S. I have to say this lockdown is great for relaxing in the garden, in sunshine, writing up these notes this afternoon. The selotape securing the brake blocks gave up the ghost in the heat shortly after the photoshoot!

Lindsay G
Posts: 167
Joined: Thu Aug 07, 2008 2:16 am

Detail Therapy - Footplate

Postby Lindsay G » Sun Jun 07, 2020 1:36 pm

More detailing, this time on the footplate. Working from front to rear :


Footplate front details.jpg

Buffers
Unlike the cast buffers fitted, those fitted to 1167 had a raised edge around the rims, so the model’s items are definitely looking lacking presently. Again the wine cellar was raided and the brass wire from around a Rioja bottle was brought again into play. This measures c0.15mm in diameter so pretty good for what’s needed. A short length was straightened between 2 sets of pliers, wound tightly around a needle file of similar diameter to the buffers 7 or 8 times (I’m sure to lose or spoil 1 or 2), cut by a sharpened blade, and the resultant hoops soldered to the buffers followed by lots of filing and sanding.

Brackets at foot of smokebox & firebox
I distinctly remember seeing etched parts for brackets at the join of the footplate and firebox/smokebox but I appear to have lost them! However, they were half etched parts just to be inserted into a space and soldered into place – hardly easy and they didn’t look up to the task. As such I didn’t mind creating them by scoring a thin strip of brass and folding it to 90 degrees, cut to length, soldered one half to the underside of the footplate and filed the other half that appeared above the footplate.

Lubricators
Two of the distinctive pear-shaped lubricators were fitted to this loco in its later life protruding from the footplate. The method of creating these was borrowed from a fellow CRA member who’d documented modelling of them on a CRA Forum thread – they’re made from 1.2mm brass bar held in a Dremel and filed to shape starting the thin pipe stem and working upwards towards the chuck.
They’re just blue-tacked into position currently until the footplate width saga is resolved.

Fittings on Top of Sandboxes
Lids for the sandbox had to be made from scratch after the problems in moving the splasher/sandbox assembly outwards, but the etched items weren’t a great representation in any case. Replacements were just some fret brass drilled centrally, filed to length, and soldered in place. Some brass wire was fitted for the handle and short lengths for the hinges.
Sanding lever assembly was made from brass etch again drilled centrally, soldered in place, 0.4mm wire inserted, then a short length of .6mm OD tube, and even shorter length of 0.8mm tube added. I’ll fit the lever to the top at the same time as adding the control rod which runs from the cab.

Safety Chains on Rear Buffer Beam


Safety chains.jpg
This pair need some refining!

These were pinched from a batch that I’d made up for 4 and 6 wheel Drummond coaches. They’re just 5 fine chain links, a hook at one end from a defunct coach accessory etch, and part of an Ambis screw coupling link at the other as the anchor. They fit into a .5mm holes drilled in the beam but won’t be glued in place until after painting.

Uniting the footplate with chassis and wheels and we have this :


rear with chains.jpg
Screw coupling laid over the hook just for effect - for once the Ambis etch links used for their intended purpose!

That’s it, rather short and sweet this time. Back to the chassis next time round.


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