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

Discussion in 'Workbenches, including workshop techniques.' started by davey4270, 23 October 2020.

  1. Threadmark: post 2

    davey4270 Western Thunderer

    No. 1. The Frames.

    A busy session this morning saw a set of frames for my next 7mm loco kit cleaned up, cut for Slater’s sprung horn blocks and tack soldered together. The following pictures and captions describe the process:

    After reaming the bearing holes for the front and rear axles to a very tight clearance the frames were tack soldered together using bearings for alignment. Clean up the etch marks around the edges of the frames. Mark the two etched bearings to be removed and clamp in a vice.

    Using a Jeweller’s fret saw carefully cut out on the etched lines and file out to the size of the horn blocks. The horn blocks will be soldered from the inside. Remove metal evenly from each side of the cut out to preserve the axle centres. This is not absolutely critical as the horn blocks will be set by the connecting rods later.

    The prepared frames still soldered together with the removed pieces above.

    The frames tack soldered together. Only the outer spacers are tacked as shown here in case some adjustment is necessary.

    No. 2. The coupling rods.

    Following on from my earlier post on assembling a set of frames, this morning I assembled the coupling rods. There are comments with each picture describing the process.

    A pair of etches to be soldered are held in a vice on two cocktail sticks after applying flux between the rods. Sprung aluminium ladies hair clips are used to hold them together (Don’t let her catch you). Apply solder along one side, capillary action will draw it in, then reverse the clips and solder the other side.

    This picture shows one set of rods.

    This picture shows the second set of rods with the brass bush overlays added.
    They will not be cleaned up until the crank pin holes are reamed out. This will give extra strength to prevent the etches delaminating when reaming.
    That’s the next job. The rods will then be used to set up the horn blocks.

    Just to mention that I have used this and must highly recommend it.
    Last edited: 30 November 2020
  2. Pencarrow

    Pencarrow Western Thunderer

    What's the kit and the prototype loco?

    (Apologies if this was in another post but I have a lot of trouble finding your previous posts and putting them in order as you use a new thread for each post. Would be easier if you had a couple of threads (layout and loco building) and then just added new subject matter to those.)
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  3. davey4270

    davey4270 Western Thunderer

    No. 3. Fitting the Horn blocks.

    Six coupled locomotives need some sort of suspension/compensation and this method was shown to me by a professional model building friend.
    A description follows with each picture.
    I chose to reverse the brass axle boxes so that the spigot faces outwards. I can then file this down to give suitable axle side play. Slater’s supply instructions on assembling their horn blocks which I won’t repeat here.

    This is where we left the model. The rods have been renamed out to fit the Slater’s crank pin bushes. I leave cleaning off the solder until after reaming to strengthen and help prevent delamination. A piece of cotton holds the pair of top hat bearings in place. This is just to prevent losing them.

    The top hat bearings are held in place (top of picture) and a pair of assembled Slater’s horn blocks are located in the middle aligned with a pair of axle jigs spaced by the coupling rods. The slots for the horn blocks will need to be widened a fraction so they the frames do not restrict their positioning by the axle jig.

    This picture shows the hair grips holding the top hat bearings and the coupling rod over the dummy axle. A minute gap can just be seen either side of the horn block.

    This picture shows a pair of soldered horn blocks. I was advised to build the chassis as a pair of 0-4-0’s which has always been successful.

    Slater’s wheels have their tyres blackened and crank pins fitted. People have personal preferences for doing this.

    The heads of the crank pin screws will need to be counter sunk. A 2.5mm drill will clear the head but drill gently by hand working up with several drills from 1.5mm. Let the drill do the work and press very gently.

    I use a spot of Loktite or similar as there is a chance of removing the screw if necessary. You’ll have no chance with superglue! The wheel has been countersunk.

    One half of the 0-4-0’s with wheels and rods fitted. The wheels turn freely with no binding. There is no point in proceeding until you are satisfied with this stage.

    Remove the wheels and Repeat the process with the axle jig to set the front horn blocks from the centre set. You will need to mark the coupling rods and axle boxes so that they will always be reassembled in the same position. The picture shows the leading and centre wheels assembled with the other half of the coupling rods.

    Rear set of coupling rods reassembled and we have a free running 0-6-0 chassis. The slater’s horn block bearings are retained by their axle keeps with 0.5mm wire loops (supplied). This is not ideal and will have a spot of Loktite added at final assembly after painting.
    Last edited: 30 November 2020
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  4. davey4270

    davey4270 Western Thunderer

    No. 4. Some Frame Detail.

    I had a day off from the wheels and started adding some details to the frames. These details are specific to this locomotive but similar parts will be on most locomotives. The parts were identified, cut from the frets and cleaned up. This gets easier as the model progresses as there are less parts to search through. When fitting detailed parts, eg rivet strips, the surface detail can be kept clean of solder by coating with metal black. This stops the solder spreading but make sure to remove it from the back! The parts were tinned with solder and sweated on using plenty of flux and, well I used, a 40W iron. Get in and out quickly so the heat can’t separate other joints. Some discolouration of the parts added can be seen in the pictures. None of the new parts have had the solder cleaned up yet.

    These are the parts to be added. From the top are parts to represent the steam chest and 3 brackets. Lower firebox sides and rear frame brackets.

    The steam chest and brackets fitted.

    Rear frame brackets. The bunkers were often extended on rebuilding by the GWR and I’d hazard a guess that is what this is. The frames would have required extending to support the elongated bunker.

    The lower firebox and ash pan seen through one of the holes in the frames.
    Last edited: 30 November 2020
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  5. davey4270

    davey4270 Western Thunderer

    Hopefully I've got all of this thread on one post. The No. 2 post is now redundant and will be deleted when I figure out how to do it. I'm not very computer literate so any advice would be welcome, no more than 4 letters to each word please. I've added 2 more sessions and was going to invite readers to hazard a guess as to the prototype. Clue: It's an 0-6-0.
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  6. daifly

    daifly Western Thunderer

    As I said in my PM yesterday, 'Report' the errant post/thread and if you ask Adrian (Moderator), he will oblige I'm sure. The 'Report' option is at the bottom of every post.
    Keeping everything together in a single thread is much better!
    Cheers. Dave
    Last edited: 24 October 2020
  7. davey4270

    davey4270 Western Thunderer

    Thank you, done.
  8. davey4270

    davey4270 Western Thunderer

    No. 5. Levelling the frames.

    Each of the axle boxes needs to have a piece of etch soldered to the top. This will centre the spring. Once again it is easier to solder the back of the etch and sweat it on to the axle box.
    You did remember to mark each component before dismantling to aid re assembly in the same position didn’t you?

    The 4 axle boxes with the etched component.

    This picture shows how the etched part fits on top of the axle box. The spring will fit around the top pin which sets the ride height and sit in the etched hole on top of the axle box. Measure the distance between the top of the frames and the inside top of the fixed rear top hat bearing. Fit a front axle box and gently file down the stop pin to the same height. A micrometer is necessary here. Once both front axle boxes have been set, place the frames and wheels in a piece of plate glass and it should be level with all 4 wheels touching. If not gently dress one of the front stops until all 4 touch.
    The centre axle boxes are treated similarly but reduce the stop pin by 0.3 mm. This will prevent the frames from rocking on the centre axle and the spring when fitted will impart weight on the axle for current collection and traction.

    The 6 brake hangers assembled. Make sure to produce 3 mirror image pairs! The one on the right has been cleaned up.
    Last edited: 30 November 2020
  9. davey4270

    davey4270 Western Thunderer

    No. 6. Fitting the brake hangers.

    The brake hanger laminations were soldered together using the same method as for the coupling rods and the brake shoe overlay added. I drilled through the the representation of the brake shoe pivot and added a bit of .7mm wire to make a small improvement. This also helps to prevent delamination with further soldering.

    I used some spare .9mm wire instead of the recommended.7mm to give more rigidity. I added 16BA washers over the wire and against the frames to represent the mounting brackets. The leading pair are seen soldered in place using a piece of card to space the brake block.

    All 6 brake hangers in position.

    An out of focus pic showing the 16BA washer. The lower wire represents the brake tie bar that will connect to the brake pull rods. The upper wire can be snipped off between the frames once completed.
    Last edited: 30 November 2020
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  10. davey4270

    davey4270 Western Thunderer

    No. 7. The Balance Weights.

    These do exactly what it says on the tin. They do the same job as the balance weights on your car wheels. They usually consisted of two steel plates, rivetted together, either side of the wheel. This was filled with possibly, molten lead to the requisite amount, which would give smoother running to the machine and hopefully reduce hammer blow to the track. Some wheels were cast with the weights integral to the spokes. At some point some were rebalanced and the cast weights were drilled out. Does anyone know why this was done? Possibly was crank axle was replaced?

    Stamper 1Aa.jpg
    The picture shows a Barry Railway F Class with " holes between each spoke. I did a single hole on my Rhymney Railway R Class by gluing a Plasticard plate, filling the spaces with body filler and then drilling the holes. Drilling 2 smaller holes could be tricky but I like little details like this.

    29 ex-CMDP Burwarton Dia B20 Photomatic a.jpg
    This is the wheels from a CM&DPLRly pannier tank rebuild No. 29. For a small locomotive it has massive balance weights and I fitted different Slater's wheels than recommended for the kit so that I could replicate this.

    IMG_2133 a.jpg
    The etched balance weight etches, slightly extended, had the spaces between the spokes filled with filler to try to replicate the massive image.

    Enough of my ramblings, the supplied etched balance weights were cleaned up and superglued on.

    unnamed 12 a.jpg
    The prototype.
    Last edited: 30 November 2020
  11. davey4270

    davey4270 Western Thunderer

    No. 8. A Start on the Footplate.

    I like to have a good free running chassis before proceeding with the body work. Any alterations to the chassis can be a major problem if the completed body needs adjustments to accommodate this. However the chassis is complete apart from the cylinder assemblies and while I’m waiting for some replacement parts a start can be made on the footplate.

    This is cut from the fret and the etch marks on the edges cleaned up.

    Plenty of work here for your rivet machine One trick to getting a reasonably straight line of “raised” rivets is to use the punch against the outside edge of the half etched hole instead of the centre. The head of the rivet punch will be smaller than the half etched hole and up against one edge will give a reasonably straight line whereas in the centre won’t be accurate giving a wavy line.

    Fold up the buffer planks and lay the chassis in place. Mark with a pencil, just visible, and put a small smear of Carr’s black for brass where the chassis would fit against the buffer plank. This will save you a job scraping away solder stopping the chassis fitting properly. Run a fillet of solder along the join. Clean up the valances, a smear of flux in their location groove and tack solder 3 or 4 spots along their length from THE INSIDE. When happy with their alignment fill with solder at intervals to spread out the heat and prevent distortion. Solder on front and rear buffer plank overlays. The picture shows the footplate without any cleaning up. Always solder from the inside where possible for this reason.

    The footplate with chassis in position after a quick scrub with “ Shiny Sinks” to remove any residual flux.
    Last edited: 30 November 2020
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  12. davey4270

    davey4270 Western Thunderer

    No. 9. Forming the Cab.

    Various details need to be added to the cab. These are easier to apply when the cab is one flat sheet before folding into shape. Raise the half etched rivets, I didn’t count them honest, add the brass window overlays to the front and the rear window coal bar protection etch to the separate cab rear etch. Beading around the cab side look outs and cab rear coal doors which had a lamp iron on the inside. I presume the lamp could be fitted from inside the cab and the door opened. Then clean up.

    The folded cab is held roughly on place with blutac and the cab rear sheet is tack soldered in place. Bend the upper rear bunker sides to meet evenly in the middle and solder together. When you are happy that everything is square the joints can be flooded with solder.

    This view shows the upper bunker rear and the cab rear tack soldered in place with the cab rear coal doors. You can just see the chassis retaining nut soldered to the bunker floor. It is recommended to solder the screw here protruding downwards and attach the chassis with the nut in case it should come loose on the finished model. I have not had a problem with this although I do flood the nut with solder. Coat the screw with metal black to stop the solder taking on the screw. I find it easier to poke the screw in with a screw driver than fiddling with a nut when attaching the chassis. You will need to do this a multitude of times as the build progresses.

    The retaining nut and bolt will squeeze the floor and chassis spacers together causing some floor distortion. This can be avoided by soldering a piece of scrap etch across the chassis spacer to fill the gap.
    Last edited: 30 November 2020
  13. davey4270

    davey4270 Western Thunderer

    No. 10. Thinking Ahead.
    Unfortunately I accidentally deleted my original post but have tried to replicate it.

    With the last few kits I've built I make the boiler/tank assembly detachable to make painting and finishing easier. The back of the tank is held against the cab front by 2 12BA screws and another 2 from underneath the footplate screwing into the bottom of the smokebox. I noticed with this kit that the cab rear sheet extends to the floor and as I have already affixed the cab rear coal doors, this will make access to the cab front sheet very difficult, if not impossible, to drill the holes.

    This picture shows that the cab rear etch will make assess to the inside of the cab front almost impossible. By removing the cab rear sheet that is only tacked in this should be possible. I have occasionally gained access through the cab rear coal doors and glued this in place after painting, or lost it, but this one sits on its hinges with no overlap so had to be soldered in.

    An earlier build photo shows the 2 screws passing through the cab front and into the tank.

    2 more screws pass through the footplate from underneath into the bottom of the smokebox.

    This shows the components separated which will make it easier for cleaning and painting.

    The 2 holes passing through the rear former there are 2 nuts soldered inside the former. Also visible is some sheet lead glued into the bottom of the boiler. This is exactly where it is needed over the 4 leading wheels which are on Slater's suspension units. This model had 4 tank formers.

    The underneath of the smokebox showing 2 similar holes.

    The partially painted model. I think this shows that painting is made much easier. Hercules lurks in the background.

    The tank sheet etch came ready formed but unfortunately it needed flattening somewhat to fit in my riveter.

    The tank assembly soldered up and cleaned. The trick here is to make yourself a cup of coffee and for 30 minutes or so relax and try to flex the etch as close to the shape of the formers as possible. Minor gaps can be squeezed onto the formers but this is very limited. More importantly the centre alignment marks must EXACTLY line up of the tank will not be square (but it's curved?), Elastic bands, lollypop sticks and Blutac are your friends here. A tack of solder (use a large piece of it will undo when you flex something) close to the centre marks so you can still see them, get all 3 formers tacked in then solder your way around. The front former is inside the tank but flush with the front as there is an overlay to fit here. The rear former is about 1mm in so that the screws will pull the tank wrapper hard against the cab front. Be careful with the centre former as it may obstruct the centre handrail knob. I have left the cut out for the motor in place for the time being to give some strength.
    Last edited: 30 November 2020
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  14. simond

    simond Western Thunderer


    its very nice. How did you do the difficult bits under the curve of the bunker?

  15. davey4270

    davey4270 Western Thunderer

    I presume you mean the curved rear panel? I haven’t done it for this model yet but I emboss the rivets and gently curve the panel to the correct profile trying to align the rivets with the ones on the bunker sides. Carefully file it until it’s a good fit as possible then tack solder in place. When you are happy, plenty of solder on the inside and extra on areas where there will be curves. Then file the corners to curves. I found the hardest part was bending a small piece of brass without rollers.
    here’s one I did earlier.
    Last edited: 29 November 2020
  16. simond

    simond Western Thunderer

    Indeed, that bit.

    Looks very nice.

    my recollection is that it is a total pita - As you suggest, I guess go slow, and bit by bit. I did one by annealing the brass and forming round a wooden former, but the the riveting was subsequently a pain, and I recall Heather having some issues a month or so ago.

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  17. davey4270

    davey4270 Western Thunderer

    No. 11. Thinking ahead part 2.
    The smoke box.

    As I explained in part 10 some thought needs to be given to locating the 4 screws and nuts that will hold the body assemblies together. The precise location of the tank and smoke box needs to be identified to fit the screws. The first job is to assemble the smoke box.

    These are the parts that will be used today. Clockwise from top left we have the lower firebox, tank front overlay, smoke box wrapper, smoke box tank support, smoke box front & rear and the boiler bottom.

    Raise the rivets on the smoke box wrapper and solder up the same way as the water tank making sure to accurately align the centre marks. This is the rear with the large slot for the tank support. Make sure you drill out any necessary handrail holes before soldering. I tack solder to the side of the alignment marks as solder on top will obliterate them.

    Smoke box front and tank support added.

    The components placed together in front of the drawing. I was going to ask if anyone fancied hazarding a guess at the prototype but this picture might be too much of a clue.

    The separate components. They can’t sit evenly on a flat surface as there are various locating tabs under the cab and smoke box.

    A view from the front also showing the tank front overlay. The body can now be loosely assembled to work out where the holes for the screws need be drilled.
    Last edited: 30 November 2020
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  18. davey4270

    davey4270 Western Thunderer

    No. 12. The securing screws.

    The model’s components need to be assembled together to work out where the screws will be fitted. I soldered on the smoke box front overlay as I thought the heat required here might disturb the securing nuts.

    The assembled smoke box and its overlay. The protruding tabs from the tank support bracket need to be filled flush before fitting the overlay.

    The overlay fitted. The 3 holes are for 2 handrail knobs and a steam Lance cock.

    Assemble the cab, tank, smoke box and the bottom of the boiler. Many elastic bands and Blutak can be used to align everything correctly paying attention to the tank being level with the footplate and everything being central and not off to one side.
    Would anyone like to hazard a guess at the prototype?

    Make a mark where the holes will be drilled, I use a large needle in my pin Chuck and the tack soldered rear cab sheet was removed as in the picture. Illustrated is a pin Chuck with drill used to make the holes through the cab front and through the rear tank former. You can see that this would not be possible with the cab rear sheet or bunker back fitted.

    Enlarge the holes to clear the 12BA screws, my 1.3mm drill bit does the job, and coat the screws with metal black for brass to stop the screws being soldered. Clean up the brass nuts, I used steel nuts once but they rusted, and tighten the screws to hold them in place. Use plenty of solder as you don’t want them coming loose. Once removed the screws will now pass out of the front of the cab and hold the tank firmly against the cab front.
    I need to make a small bracket to fit underneath the smoke box to affix the front.
    Last edited: 30 November 2020
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  19. davey4270

    davey4270 Western Thunderer

    No. 13. Fettling the components.

    Other members of the family are home over the weekend so, unfortunately, my modelling has to take a back seat. Some work has been done although not too much progress can be seen. Work has included fettling the main body components so that they fit snug and squarely, reattaching the cab rear sheet and a making start on forming the bunker rear sheet.

    The lower boiler component was not sitting level with the footplate and sloping up slightly towards the front. This was traced down to the smoke box wrapper being about 1mm too long on each side, how did I miss that? It was filed flush and the boiler base is now level. Unfortunately it doesn’t show in the picture.

    The chassis has not been forgotten as I wait for some new parts. I hasten to add that there is nothing wrong or missing from the kit but it is an old, early version and new, improved lost wax castings have been ordered. I have assembled some components and clockwise from the top we have sand boxes, cylinder frames, slide bars and the slide bar supports.

    The dreaded bunker rear sheet with rivets raised. Did you spot the missing rivet? Yes, it’s been sorted.

    Gently curve the top half to the appropriate shape. This is not as easy as it sounds as the brass is particularly hard and a small piece gives little leverage. I have a small vice and open the jaws about 3mm. Place the top of the panel in between the first 2 rivets and flex the panel Impart only the slightest bend and repeat between the next pair of rivets. Continue down to the double cross row of rivets. Try the profile against the outside of the cab rear side sheet and repeat if necessary. It is probably better to slightly over form the curve as it is quite easy to straighten it a touch. You will need to round the top corners and I needed to remove about 1mm from the top edge but carefully check regularly if you are working at the correct position. The edges of the side panels will be filed round to give the rounded corners not the rear sheet.

    Nearly there, some more fettling tomorrow.
    Last edited: 30 November 2020
  20. davey4270

    davey4270 Western Thunderer

    13A. More Fettling.

    I’ll call this post 13A as, once again, due to weekend family commitments little work has been done. These notes cover my thoughts at the present time but may/will change as the build progresses.

    More careful fettling on the lower, rear bunker sheet has obtained a close fit and after tack soldering to accurately to align it the joints were flooded with solder as suggested in the instructions. Take care not to solder it to the floor as it is easier to clean up away from the rest of the model. A couple of rubber bands help hold the cab component to the floor.

    A view of the soldered back before filing to shape. The lower centimetre on each corner was soldered after removing from the footplate to prevent attaching it to the model. Unfortunately the upper row of rivets don’t align. If I can’t live with this, I’ll remove them and replace with dots of superglue before priming. This works quite well, draw a pencil line for the row and apply dots of glue with a pin.

    A start on filing to shape along the top joint. More to go and you’ll lose a few rivets but these will be replaced by the same method.
    Last edited: 30 November 2020