Crymlyn A Shop Techniques. Agenoria 10/7 Avonside 2195 CWM MAWR

davey4270

Western Thunderer
14. Fitting the Cab.

More fettling was required before I was happy with the shape of the bunker lower rear panel. I must admit that this task seemed almost endless, perhaps I need new files! Anyway one of the Crymlyn A Shop Boyos, Percy Veerance, helped and we got there in the end!
Once again, captions with the pictures.


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After much filing I am happy with the profile. The 90’ angle on the side corners was filed to give a slight radius. I also decided to add the bunker top beading at this stage purely as I thought it might be easier holding the job as a smaller component before attaching it to the footplate made it a tad unwieldy.


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Before attaching the cab assembly I estimated where the vertical cab side handrails would go and drilled the 4 location holes. This would be rather difficult when the cab is fitted so I drilled the holes under size. These can be enlarged from underneath when required but I didn’t fancy trying to mark the holes from underneath.


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The cab assembly is tack soldered to align it accurately then the joints are filled with solder. I could get my 40w iron on the inside of the bunker sides but not at the back as unfortunately the iron is too big. The solder flowed around the rear corners but not across the back which is tight against the floor so hopefully this won’t be a problem. My 25w Antex wasn’t quite man enough for the job and I didn’t want to dwell too long in case the bunker rear started to unsolder.
The advantage of soldering from the inside is that virtually no cleaning up around the outside rivet rows is necessary. The body has had a scrub with “Shiny Sinks” and HOT water to remove any flux. The effect of the “Shiny Sinks” on the brass is clearly visible.


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I also made I made a start on the cab interior by cleaning and folding up the floor and bunker front. The coal door was added and a handle fitted to it.
 
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davey4270

Western Thunderer
15. The Cab Handrails.

Adding small details and getting them straight and square while trying not to bury them in solder is very time consuming. You will spend hours doing this with little visible progress. This can be said of the handrails. Wonky or uneven handrails look terrible although there are pictures of the prototype where they are damaged or missing. Unfortunately if you replicate a bent handrail on your model, it looks awful.


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The cab beading etches are cleaned up and tinned. Only cut off the one you are fitting as they are very small and their brethren will readily play hide and seek on your workbench. I found them a fraction narrow and would have replaced them if the inside handrail end hadn’t been half etched to wrap around the upright cab door handrail. A spot of filler later me thinks. The picture shows one held in place with aluminium hair grips. A spot of flux, touch with a hot iron and job done.


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The beading is wrapped around the upright cab door handrail which is threaded through the hole you drilled through the footplate earlier. If the handrail is not quite straight, GENTLY use the side of the drill you used as a file to elongate the hole to allow the handrail to sit straight. A touch of solder on top of the handrail/beading and another under the footplate secures it. File the top to size.
Fold staple shaped wire for the bunker handrails and pack them with a suitable piece of wood (I’ve used a piece of a coffee stirrer here). This will pack them out to the same distance and press the wire gently against the packing while you solder from the inside. Don’t dwell too long with the hot iron as you don’t want to desolder that lovely bunker rear do you!


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A view from the other side showing the rest of the handrails. The Prototype did have rather thick handrails. I’ve removed the cab rear coal doors as I think they must open inwards. If the bunker was full they physically couldn’t open outwards. Then I can’t see the logic in having a lamp iron on the inside. Anyone got any ideas?
1f914
A lamp iron on the outside could replace the one on top of the bunker and give easier access by opening the bunker doors into the cab.


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While my soldering iron was hot, I made up the cab steps. Simple clean up, fold up and solder.
 
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davey4270

Western Thunderer
A cropped photo of the sister loco (the one numbered one less than yours!) appears to show the doors opening inwards.
View attachment 132705
Dave (who knows the identity of the build but mustn't reveal it!)
Thank you kind sir. I presumed that inward opening doors would be essential as it wouldn't be possible to open outwards unless the coal was below the door level. I still can't see the logic of having a lamp iron on the inside of the door as it would prevent it opening fully and be as much use as a chocolate teapot! I actually saw these for sale in my local motorbike shop as Christmas presents a few years back. It must be a mistake on the instructions and the lamp iron probably fits on the top of the bunker or perhaps a mount for a spare lamp inside the cab?
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davey4270

Western Thunderer
Davey, part 67 is not a lamp iron but the catch/latching mechanism for the inward opening doors. This would have to be substantial to take the weight of coal behind the doors when fully coaled up.
HTH
Dave
Of course! I helped restore and fire 9642 so should have known better. The fact that this was not replicated on previous kits threw me and I think I had a touch of dyslexia or too much Jim Beam and mistook part 76 for 67!

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davey4270

Western Thunderer
16. The Tank Handrails.

I made a start on cleaning up the three penny bit effect on the lower tank curve (although what with inflation and decimalisation perhaps it should be the 50p effect) and then made a start on fitting some of the handrails. Thanks to “Dangerous Davies” on Western Thunder the conundrum of the fitting on the bunker doors has been solved. It was an arrangement of bars to hold the doors shut and I mistook the part number 76 for 67. I must be getting a bit dyslexic in my old age or it might be too much Jim Beam.
As always there are captions with each picture.


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I used a file with a wedge shaped cross section as it has a smooth section on the wider side. I used my finger nail to protect the rivets and and gently worked the file around each section until it was all all shiny meaning the high lines were smoothed down to the lower parts. My fingers weren’t holding the file but tucked away while my other hand worked the file. This was just posed for the picture.


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Another view showing a smoothed panel on the left and the visible lines on the right.


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I soldered the handrail knobs from the inside using a piece of handrail wire to align the 3 knobs before soldering, the inside of one knob being visible centre right. I put the cab/tank locating screws in to hold the nuts tight against the rear former in case they should work loose, visible top right. The 2 handrails near the tank filler were also fitted.


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I also soldered the 4 footplate handrail knobs in place again from underneath.
 
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davey4270

Western Thunderer
17. Attaching the Smoke Box.

As I mentioned in one of my earlier posts the plan is to attach the smoke box/boiler assembly to the cab and front footplate with 4 x 12BA screws. I have covered fitting the 2 captive nuts inside the rear tank former and today I tackled the smoke box.
As always, captions with the pictures.


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I had a short piece of “U” channel spare and used this to form a bracket to hold the retaining nuts. I have previously used a piece of brass scrap folded to an “L” shape. This was tack soldered into place, as in the third picture, and the superstructure was assembled with rubber bands and Blutac. I estimated where the 2 holes would be underneath the footplate and drilled 2 pilot holes through the footplate and just enough to leave a mark on the smoke box bracket. Un solder the bracket and drill through the 2 holes where marked. Coat 2 screws with metal black and I used another 2 nuts coated with metal black underneath to hold the 2 clean top nuts in place. Solder the top nuts in place and resolder the bracket in position. Hold the sides of the smoke box tightly in position throughout these operations as it will try to spring out. The bracket needs to be slightly up from the base (0.5mm is sufficient) so that the smoke box will pull flush to the footplate.


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The 2 holes drilled through the footplate. These need to be enlarged to 1.3mm to clear the 13 BA screws as will the holes in the smoke box bracket.


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The bracket soldered in place and some sheet lead glued in. Leave the screws in place while soldering in case the captive nuts move with the heat.


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The 4 tank lifting brackets were added with their base plates. Details like this take so long! A stop for the water filler, centre right, along with a tank vent, centre left, we’re added. A pair of steps on the tank lower right either side will complete the soldering with a few white metal fittings to finish. These will be Araldited on. I have used low melt solder successfully but find it comes apart with HOT water when cleaning. Araldite also gives you several minutes to make small adjustments.


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Vertical wire fittings can be significantly strengthened by bending a tail and soldering inside. The picture shows the 2 tails from the filler lid stop and tank vent.
 
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davey4270

Western Thunderer
18. Boiler Barrel & Ballast.

Assemble the smoke box, tank and lower boiler barrel aligning everything accurately and tighten the smoke box screws from underneath. Fit the chassis and check that everything sits squarely. I try to keep the chassis fitted at all times as without it the footplate is rather flimsy and easily distorted. When you are happy carefully ease the tank out, mine had to be flexed slightly forward to clear the cab spectacle rims. Mine also had a bit of slack in the slot at the smoke box end and about 0.5mm clearance. Check that the boiler bottom is level with the footplate, pressing mine down to the bottom of the slot in the smoke box cured this, and push back against the firebox. The boiler bottom will be soldered to the smoke box and merely slot into the firebox after painting so we don’t want a gap here. When you are happy, solder the boiler bottom to the smoke box. Check that the tank will still fit as it slots into the top of the boiler bottom against the smoke box.


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The bodywork assembled to check for alignment. The Blutac holds the boiler bottom’s upper edges close enough to fit inside the tank. Check this still fits inside as you solder. A small tack first, check for alignment then solder properly. The slight gap at the front was filled with solder. Do not solder to the firebox!


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The slots at the top of the boiler bottom against the smoke box are visible here. Some sheet lead can now be added. The suspension system on the model consists of sprung horn blocks on the leading and centre axles with a rigid rear driven axle. Weight needs to be forward of the rear axle to compress the 4 small but strong springs on the other axles. Strips of lead were cut, narrow at the bottom and getting wider towards the top. Scratches on the surfaces of the lead will help the glue adhere, I used “UHU”, actually adding 109 grams exactly where it’s needed over the sprung axles.


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H]ow could I be so precise with the weight?
Well I weighed it before and after, you can see my calculus at the top of the picture. Bet you wish you’d paid attention in maths now! Lol!
Here’s my attempt at the coal doors retaining levers, could have been straighter but I think it’s too delicate to adjust and won’t really be visible inside the cab anyway.
The “red carpet” is a piece of card I use to insulate heat from the surface of a small piece of plate glass that I often solder on.


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I made a start on the firebox, raising the rivets on the front and soldering on the wrapper.
This rather strange pattern is on a place mat, just in case you were wondering.
 
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davey4270

Western Thunderer
19. Rear Tank Supports.

Once again due to family commitments over the weekend, I’ve done little work. I managed clean up and fold the rear tank supports and couldn’t understand why, after carefully levelling the tank, they were to big to fit into position without raising the rear of the tank out of alignment. This is not like Mr. Stamper whose kits are generally very accurate. After about 30 minutes removing and refitting the tank along with much muttering and cursing I noticed that there were half etched locating recesses to position the supports, doh!
I also managed to mark the position of the tank front steps. The General Arrangement drawing shows them to be level with the top hinge on the smoke box door so I scribed a little mark level with this. I’ll solder these on tomorrow and hopefully solder the tank to the smoke box. I also cut another strip of lead to fit on top of the exiting pieces which can be easily slid in if necessary but would be difficult to judge the size when the tank is fitted to the smoke box.


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The half etched locating slot for the tank supports. I must have been pushing the support against the firebox which prevented it from fitting into the slot. The tank support is now located about 1mm away from the firebox side.


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The tank support soldered in position. So much for me accurately spacing the brake hangers from the wheels! Hopefully when I fit the brake pull rods they will be rigid.
 
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davey4270

Western Thunderer
20. A Removable Tank.

Work today saw some detail added to the tank and then soldering it to the smoke box to give a removable component to help painting. Some thought was also given as to which motor to fit.


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I added the tank front footsteps while the tank was removed from the smoke box which gave more space to attach these small, fiddling components. Once happy with the positioning of the tank the 4 retaining screws were inserted and tightened holding the tank securely to the cab/footplate with the tab of the lower boiler barrel located freely in the firebox. I applied a small amount of solder either side between the base of the tank and the smoke box and added the 2 piece bracket that held the tank to the top of the smoke box, the soldered bracket doing the same job on the model. The steps and bracket are visible in the picture.


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The tank component is removed from the cab/footplate section which will make painting much easier. Also visible is the motor axle mounting. I’m not sure why this is referred to as a “gear box” as it’s certainly not a box although there is one gear.
1f914



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A view from the cab end of the tank component showing the sheet lead which stops short of the firebox where the motor will live. There is room under the centre tank former for one more strip of lead. This is already cut to shape and can be slid in if necessary.


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I am fortunate in having 2 spare Mashima motors. An 18/24 top (an extremely rare specimen) and an 18/30. I presume the 18/30 will be significantly more powerful than the 18/24 the kit is designed for and although it will be a tight fit, I will try to accommodate it to make the model more powerful.
 
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davey4270

Western Thunderer
I wonder why fit the more powerful motor when its full potential could never be realized in this loco?
Hi Larry.
I am quite fond of small Swansea area shunting locos and the others I’ve built mostly have 18/30 or 18/33 motors. With small wheels and 40:1 gears they will quite happily pull 50 wagons at walking pace on my local test track. I just wanted to maintain the status quo so to speak.
David.
 

davey4270

Western Thunderer
21. Detailing the Smoke Box.

Once again the work today included many fiddling details which take time and care to prepare but show little progress to the casual observer of the model. I added 2 handrail knobs set at an appropriate angle for the small curved handrail which follows the upper curvature of the smoke box, the steam lance cock, a washer for the steam blower pipe flange on the side of the smoke box and Araldited the white metal smoke box door on. I will fit the blower pipe made from some copper wire after painting. I don’t think the paint would have lasted long with the heat from the steam passing through it and it’ll add a bit of contrast to the model.


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The tank and smoke box are starting to look quite cluttered with all the added details. The washer for the blower pipe flange is visible on the side of the smoke box. I also added the tank balance pipe from brass wire again with a couple of washers to represent the flanges. I used some 1.2mm brass wire instead of the 1.0mm supplied and recommended. 0.2mm difference is laughable but it certainly makes the balance pipe look “meatier”. I also use this wire for the cross bar on wagon brake gear. It makes quite a difference. I add the handrails just before priming as they usually get bent with handling the model. The lifting rings will also be added after painting.


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The chassis was feeling neglected while waiting for new cross heads, so I soldered on the rear sand boxes to cheer it up. There’s no sign of a filler cap in my pictures so it must have been on top hidden in the gloom. No wonder they were removed and fitted in the cab!
 
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davey4270

Western Thunderer
22. A Start on the injectors.

Not much work done again today but I made a start on the injectors. I rather like seeing brass injectors with copper pipe work on steam locomotives and try to replicate this on my models. This kit, an early version, came with mostly white metal fittings including one piece injector assemblies. Fortunately I had some spare brass castings from other built models to substitute these and also found a pair of firebox back head clack valves. A study of prototype pictures showed the feed water entering the front of the cab and not re emerging so must have entered the boiler through firebox clack valves. There was an internal pipe carrying the feed water towards the front of the boiler from each of these.

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Top is the supplied white metal injector. The water feed top left has a square location peg, the square holes underneath the tank had brass washers soldered over them to represent a flange and give a round hole to fit the brass injectors. I drilled locating holes for the copper wire to be soldered into, about 1mm is plenty for a good soldered joint. The cast brass is extremely hard and is slow work with a pin chuck and drill with 4 holes in each injector. The water feed cock to the left needs to be reversed with the operating rod passing to the right over the injector as on a pannier tank. I’ve just drilled a hole on the right hand side for this. Study of the prototype pictures shows the live steam supply emerging from between the firebox and the rear tank support so I’m glad there’s that gap between them. Well done Mr. Stamper.
One of the Crymlyn A Shop Boyos, Parry the Pipe, will be busy tomorrow.


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While my drills were out, I made a start on hollowing out the chimney. I’m glad that wasn’t cast brass! It’s not finished but placed here for effect.


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Also soldered in were the little bits of 0.7mm wire to represent the bolts on the guard irons.
Stop Press. The cross heads have arrived!
 
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davey4270

Western Thunderer
23. Injectors and a start on the cylinders.

One of the Crymlyn A Shop Boyos has been busy today. Parry the Pipe has been working hard fitting up the injector pipe work while the rest of the Boyos have been busy making a start on the cylinders and machining the slide bars.


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Half of Parry the Pipe’s efforts are shown here with the assembled component resting in place. The overflow pipe is not soldered as it would be almost impossible to remove the injector component for painting. The water feed inlet plugs into the bottom of the tank and the feed water outlet pipe passes through the cab front underneath the rod which operates the water inlet valve. The steam inlet pipe is just visible entering the injector centre just below and to the right of the water inlet valve having emerged from between the firebox and the rear tank support. The overflow from the bottom passing through the footplate.
The injectors will be refitted after the body is painted when assembling the tank to the footplate/cab. All that’s needed is 6 hands and 3 pairs of eyes. The overflow pipe will be superglued in place after final assembly.


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Today’s components cleaned up ready for work tomorrow. The centre right chassis spacer has had a bit more removed from the cutout to clear the gearbox. A Branchlines specimen was supplied which is fractionally larger than the Agenoria item although is the same height from the axle.
Lower left is a pair of cylinder frames and centre left are the laminated slide bars. The replacement cross heads have a slot of 6.4mm and the slide bars have been filed to an internal gap of 6.3mm, final fettling to follow after assembly of the cylinders. These measurements are easy with an LED callipers. Centre right is the firebox and finally Parry’s injectors.
 
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davey4270

Western Thunderer
24. More on the Cylinders.

Work was interrupted today by some little sh1t hacking my Facebook account. Spurious messages were sent out to many friends so if you got one apologies and please don’t open it. It will give you a Facebook login page to view and this is how they will get your login details.
Anyway before I was rudely interrupted, 6BA retaining screws were soldered into the cylinder frames and the locating tabs bent out and given a fillet of solder to strengthen them. The slide bars were soldered in making sure to produce a mirror image pair. The 4 overlays were soldered to the outside faces of the slide bars and the assemblies cleaned up.


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The cleaned up cylinder frames. The top frame shows a fillet of solder inside the fold. I put a hint of flux in the half etch before bending to 90’, check with a square to make sure or your cylinder won’t be shaped properly, melt a small piece of solder and draw it along the fold slowly with the iron.
Do the same thing with the locating tab as shown in the lower assembly and solder the 6BA cylinder retaining bolt in place.


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Remove the half etched end piece on the slide bars and fit into place in the cylinder. Tack solder at the front and check alignment. There is a small amount of play in the back end to check the slide bars are parallel with the frames. Adjust if necessary and solder in place from the inside. Use Blutac to hold the ends of the slide bars if necessary. The near cylinder slide bars are not bent, it’s an optical illusion. Solder the 4 slide bar overlays to the outside of each slide bar. Put some flux on the side of the slide bar, place the overlay and hold in position with 3 ladies aluminium hair grips. Adjust so that the inside face is level, this is where the cross head will sit, and solder from above. Remove the hair grips and file back to the outline at the top and bottom of the slide bars. The whole lot can then have a good clean before the cylinder wrappers etc are fitted. You may find a small amount of solder where the slide bars exit the cylinder which will stop the overlay butting up against the cylinder, this needs to be removed.


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The Mashima 18/30 motor in place. Obviously the end shaft will need to be removed and I have already filed “shoulders” in the cab front. It’ll be a tight fit but should be achievable. I managed this with 359 HILDA with similar clearances although I might have to raise the firebox a millimetre or so. The flexibility of a working model using a bigger motor is well worth the effort.
 
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davey4270

Western Thunderer
25. The Cylinder Wrappers.

Once again the weekend has drawn me away from the workshop to entertain the family so little progress has been made with the model. However I did manage to fit the cylinder wrappers which is a another very fiddling job.


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Form a curve on the wrapper by rolling a suitable sized tube over the wrapper resting on several folds of kitchen roll on a soft carpet. Gently roll back and fore until a suitable shape is obtained. I used an old scalpel handle which is slightly wider than a pencil. With the cylinder resting on its front, the slide bars would be vertical, place the bottom of the wrapper flush with what would be the bottom of the cylinder and also flush with the front resting on the work surface and tack solder the 2 corners. Check all is square otherwise the wrapper will taper off and not follow the shape of the cylinder. Solder evenly alternating between the front and the back around the cylinder former up to the top. Be careful that the top of the wrapper doesn’t slip inside the former as it will push it to one side. There is only about 1mm extra width with the wrapper so not much to play with.


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The cylinders with the wrapper fitted in place on the model. Also loosely fitted is the cab floor/bunker assembly.
 
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davey4270

Western Thunderer
26. Slide Bar Supports and Vacuum Pump.

Work today included fitting the front cylinder covers, fettling and fitting the slide bar supports and assembling and fitting the vacuum pump cylinder.


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The front cylinder covers were soldered on about 0.5mm in from the outside edge, this was to represent about 1 inch of lagging. The bolts, half etched to be raised as rivets, were arranged with 2 bolts level on the bottom. In my working life I had observed pipe fabricators doing this with a spirit level and was told that this was standard practice for alignment. The cylinders were bolted to the frames and aligned to point directly at the centre axle. I put an Allen key in the axle bolt and sighted it by eye. Tighten the nut and check the cylinder hasn’t moved. Fettle the left hand slide bar support until it fits being level with the top of the frames, at right angles with the side of the frames and also at right angles with the slide bars. This will slope forwards at the bottom. Ensure it doesn’t protrude above the chassis or the chassis won’t sit flush with the underneath of the footplate.
I failed miserably assembling the vacuum cylinder on a previous model, ex CM&DPLR 29, and used a cast brass item that was also in the kit. I managed to drill this out almost straight without a lathe, more by luck than judgement, and had an absolute nightmare soldering it in the correct position.
However this time I was more experienced, fortunate?, and successfully assembled it. The picture shows the main component soldered to the slide bar support around an .80mm drill bit with a brass overlay on the front of the slide bar support. My friend Blutac helped here. I bent the wrapper for the vacuum cylinder around a needle file handle and shortened the wrapper to be a perfect fit or preferably a fraction shorter before soldering it in place. I was afraid that if it was slightly too big it would push the pump body away from the slide bar support. File any excess wrapper from the back of the cylinder.



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CM&DPLRLY 29 with the cast brass vacuum pump although you can’t tell when it’s covered with a coat of paint. Hopefully this picture gives an idea of the finished product.



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Assemble the right hand slide bar support but with the vacuum pump cylinder attached in the same manner as the other side. If necessary file about 1mm clearance between the outside face of the slide bars and the inside of the down leg of the support to allow you to insert the cross heads. This is obviously easier to do before assembly. When happy with the alignment solder the locating tab inside the top of the frames and after checking alignment once again solder to the ends of the slide bar supports. The spread of the solder can once again be controlled by painting around the area with a small amount of Carr’s metal black for brass. I was concerned that the vacuum cylinder would desolder but I had no problem although I was as quick as possible soldering the support to the slide bars. Carefully remove the etched spacer between the slide bars, I drilled several small holes to weaken it, and file them flush with the back of the support bracket.
 
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davey4270

Western Thunderer
27. Fettling Cross Heads.

Even though I carefully set up the slide bars and support brackets a great deal of time was spent removing minute amounts of metal and solder to get the new cross heads to fit. There is no easy way to do this, just keep checking where contact stops it sliding in and remove it. Ideally the cross head should fall in and out under its own weight with the influence of gravity and without any slack. All valve gear on electrically driven locomotives is purely decorative and should impart no resistance on the motion. Excessive slop which allows the cross head to rise up and down with the con rod looks toy like so try to avoid this.


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Once I was happy with the fit of the cross heads I soldered on the gland/stuffing box assembly. I used a 2mm drill through the piston rod hole to help align it held in place by my old friend Blutac.


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I’m sure the stuffing box should be folded into a “square” but with the outer parts folded outwards it can easily be soldered to the outside of the slide bars. There is no slop with the cross head, the markings on the casting give an optical illusion.


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The cross head in its outer position. The travel of the cross heads will be controlled by the throw of the crank pins.
 
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