Category Archives: Workbench (stock)
Scrap Tank Test Build Part 9 – Finishing the Body
I have now had the castings back for the various fittings for the Scrap Tank; the masters being in part my own 3D prints and some turnings that I commissioned from Jeremy Souter. This is what they look like:
I did not seek to do everything for the whole model as some parts are available from other suppliers and I did not want to duplicate their work. Thus, I needed to get the safety valve/safety valve bonnet from Alan Gibson, a smokebox door from Lochgorm, a whistle from Markits and smokebox door handles from Comet.
Once these, along with the remaining handrails, were fitted, the body is complete and it certainly appears to be taking on the character of the real thing so far as I am concerned!
So next up will be the cylinders, crosshead and connecting rods!
The Cruellest Cut – Carrying on with Hornby’s Gresley Buffet
The first task in dealing with ready to run vehicles is to work out how to get into them – not always as easy as it sounds! In this case, this is achieved by slipping finger nails between the sides and the underframe solebars; this releases four catches and the top pops off. The interior then slips out without bother but the glazing is a little more tricky as it is secured with some very gooey glue. Whilst this releases the perspex relatively easily, it was difficult to then remove the remaining glue – I found it best to do this by rolling it with a thumb and accumulating the residue on a scrap of paper but it was a pain getting it all off.
Prior to attacking the model with knife and blade, a sensible precaution is to protected all of the areas that are not to be cut with masking tape, which you will see I have done. This was effective but I did find that I dislodged a filler pipe when I removed it, so perhaps a slip of paper over these would be prudent next time.
Then it was time to get cutting; I varied between using a razor saw and a scalpel to cut a grove by using parallel cuts but in both cases it is important to cut to the waste side of the finished line. I found that it was best to work to an existing bead line, even though when working to the saloon end of the coach the bead was the side of door jamb (this is where I found the knife best and I made sure this was one of the first cuts to be made) so that there was no stress on the thin piece of material. By the time the cutting had been finished the holes were quite big!
Nearly all the cutting done now; but the last panel to the right did also get cut away
It pays to dress the sides of the opening with care so that they are straight and square as this makes the fitting of the infill pieces much easier. These should be cut fractionally over large and then sanded back by small degrees checking regularly to determine if it fits and taking care to ensure that the square/straight edges are maintained. Once it fits, I let it into the hole and secured with butonone and then left it to cure for a couple of hours so that I did not disturb it when I subsequently fitted the beading. This was formed with 0.2 * 0.2mm microstrip and these needed to be set out with considerable care – aided by the use of venier calipers – to get them regularly spaced and vertical. Even the most minor of inconsistencies detract from the affect.
Replacement panels now in place, including a partial infill of the window by the door
Next up was the removal of the various roof vents and cowls as these too changed. I suspect that these were no consistent across differing vehicles and it is quite difficult to determine what goes where but I was assisted by some photographs from here. Utilising some of the vents salvaged from the Hornby model and also from Comet Models, the latter generally with their shields filed away as the roof views I have have straight flanges as shields – which I formed with brass strip as I though plasticard would be knocked off.
Roof vents in place, based on a photograph of the roof of 9132 at SRPS in the 1970s. I also noted that the alarm gear on the roof was at the other end of the vehicle in comparison to the Hornby model, so this is going to need to be cut away and recreated at the opposite end.
Dinner Time – A Gresley Buffet for Portchullin
Whilst my memories of the former HR’s line from the 1970s and early 80’s only ever had BR mk1s as coaching stock, there were occasional strays coming onto the line in the form of Thompson/Stanier full brakes and Gresley buffet cars. As I understand it, a pair of the latter were indeed the regulars on Glasgow to Inverness trains. So, wishing to enliven my passenger trains up a little on Portchullin, I thought that it was time that the punters had a buffet car to buy that notorious rock hard pork pie in!
Hornby introduced a range of Gresley stock some ten years or so ago and they represented a significant step forward in terms of quality of coaching stock generally and particularly in comparison with their predecessors. If I recall correctly there were some problems with the direction of the graining that Hornby quite quickly sorted out and the teak coaches look the part – especially as to do them oneself is a very challenging exercise. The only vehicle that they offer in blue/grey is the buffet and this is what it looks like.
As with nearly all r-t-r models now a days, the finish is exemplary and at first glance it definitely looks the part, capturing the curves at the roof very well and it will stand out nicely in comparison with the remainder of the coaches on Portchullin. It is true that the panelling cover beads are a bit thick, which is not visible on the teak finished coaches due to the graining but is rather more visible on the grey here but as I am going to weather down this vehicle to a fairly battered condition, I am hoping this will fade to a lessor impact. Some commentators criticise the tumblehome being too slight and the bogies being subtly incorrect but I am struggling to see either defect so will ignore these points.
What I will not be ignoring, however, is the most significant problem with the model. These vehicles only made it into the 1970s because they underwent a fairly significant rebuild in the 1950s. Hornby have simply painted their LNER era model in blue/grey whereas the rebuild affected their appearance on one side quite significantly. Here is a comparison and you can see that three windows have disappeared altogether, the panelling arrangement on the near end is different and the roof vents were adjusted to accommodate the revised internal arrangement.
I have seen moans on the forums about this error and even moans from people at the people who are moaning. I make no criticism of Hornby at all; it is obvious that the revised tooling that would have been necessary to correct this would have made the model uneconomic. Therefore, we have to either accept it is as it is or pick up our tools to correct it. I make model railways to do simply that, make them and I derive the greater proportion of my satisfaction from building or modifying things – thus I simply see this as part of the pleasure!
So my next project will be a bit of plastic surgery on an old lady, to get her looking proper! I do not propose to do a full respray so it is not that difficult to do; so to both the moaners and the moaners at the moaners, I would simply encourage you to pick up your knives to follow suit!
Thank you to Hornby for providing the base model and also for the use of the colour photos. The prototype photograph is courtesy of Paul Barlett.
Transfer Update
Back in November 2013, I hinted that I was trying to crack transfers for the Highland’s locos in LMS days; something that is not realistically available via other sources and there does not seem to be much prospect of anyone else doing them.
Anyway, hopefully, I have cracked all I need to with regard to these and the final artwork is complete. This is what it looks like – hopefully it has covered all the locos you might fancy!
Also on the sheet are one or two other things; but I am less certain that these will work so I’ll keep these as a secret until I find out.
The intention is that these will be available in 4mm & 7mm scales; pricing to be confirmed but I am afraid they will be fairly expensive as the production run is not big and you 7mm chaps in particular eat the page with the size of the prints!
Once they come in, I decide whether they are viable.
Scrap Tank Test Build 8 – Casting Masters
The update on the Scrap Tank test build shows it looking like this:
The eagle eyed, and indeed the slightly less than eagle eyed, amongst you will notice that this is not a whole lot different to the last update, just a few fittings have been installed – basically the ones I could glean off other things; the safety valves/bonnet and smoke box from Lochgorm Models and the clack valves from Alan Gibson (but much cut down as they are really much too big). I have not been able to fit any other castings because they don’t exist, so I have had to do some more work on these.
So it is back to the CAD machine to draw up a series of 3D masters; in the top view some piston rods/part of the cross head, rear sand boxes, clack valves (now the right size which is much much smaller) and some lubricator valves. The bottom view has some tank filler lids, front sandboxes and piston ends.
These have been printed for me by Alan Butler of Modulu who is a new entrant in the field of 3D printing and has a system/machine that can do really small parts very well indeed; definitely better than Shapeways. Alan is a railway modeller here and blogs here – well worth a look I suggest and if you are thinking of having some things printed then I would get in touch with him.
I did not get Alan to print the dome and the chimney, partly because I had my doubts that the print would do the fine lip of the metal where it meets the boiler but mostly because I just could not work out how to draw the damn thing! Instead, therefore I commission Jeremy Suter to make these for me:
……..and very fine the look too!
So, these are the masters all sorted and they will shortly be sent of for casting. I will be using lost wax again, as I much prefer this to white metal; although I do accept that the better white metal casters do do a grand job.
Scrap Tank Test Build – Part 7; Boiler Assembly and Finishing the Cab
Next up is the finishing of the detailing of the cab. Common with many tank engines there were grilles over the rear windows. For these, I toyed with the idea of doing these as a single etch, a bit like the Mainly Trains one (and possibly others) but elected instead that the slight roundness of the bars needed to be captured, so this meant that brass rods were going to be required. If I had either etched small holes or soldered these on top of the cab etch, I felt that getting consistency of spacing was unlikely and that this would detract from the finished effect. Thus, it was time for a little jig.
This jig is simply a sheet of brass with holes for the wire at the appropriate spacings along with half etched lines arranged such that when the jig is folded over, the wire is trapped between them. This is what it looks like with the wire in and the jig folded over (along with a dab of solder to hold it all still):
You will note that in the picture above, I have trimmed the wire rods to a gentle curve to reflect the curve of the spectacle plate and in the picture below, this has been soldered on the ring around the window. The jig is then snipped off and the rods can be cut away. I found that by using a scalpel, it was possible to cut a nick in the rods and then the wire could be carefully lifts so that it snapped at the point of the nick. It was necessary to ensure that the rods were soldered well to the sides as if this joint failed it was then pretty difficult to get them soldered back down neatly; I will include a space jig in the production etch of the kit to give the user a second chance!
There is also a beading around the cab side openings, a common feature on pre-grouping locomotives. This was relatively simple to fit, although I did make it a tad too fat deliberately to assist in the process – it can then be filled back to a thinner dimension and in the process any slight irregularities taken away in the filing. In this example the stanchions are probably a bit far away from the cab sheets, so there will be a slight adjustment on the final version.
Also worthy of note is the cabside number plate, which I am dead chuffed with. This is a cruel enlargement as the whole plate is only 6mm across and to clearly be able to read the text which is only 0.7mm high is pretty good I reckon!
After finishing the cab detailing, it was time to add the boiler onto the tanks/running plate and she is beginning to look like the real thing, although perhaps looking a little naked due to the missing dome and chimney at present!
I have fitted a safety valve bonnet and safety valves from those intended for the Strath/Loch and available from Lochgorm Models. I also formed the front splashers, which I had tried to make easier by the use of some tabs and formers. These did assist in the assembly but I then found that they fouled with the wheels, as I had made the splashers true to scale and the tolerances did not allow for the tabs. I will have another think here and might come up with a jig, as splashers are sometimes a bit painful to fit.
And this is what she presently looks like; definitely beginning to look like the real thing (a reminder of which is below). For those of you that are coming to Scalefour North I will bring her along for you to have a look at. As we are now about up to date with her construction (you didn’t think I can build that quickly did you?!?!) and because I am away the whole of this weekend at Scalefour North, there will be a hiatus a bit before the next posting.
Scrap Tank Test Build – Part 6; Boiler and Running Plate
Now that the much of the bulk of the above running plate work has been completed, the running plate valences can be fitted. As these are nearly always long and thin, they are prone to distortion in the kits I have built – so it is time for another jig!! This one holds the valences at numerous places to stop it flexing and to hold it straight.
With this, it is a doddle to fit the valences in their correct place and solder them without distortion. I did find that the running plate flexed significantly at the end of the tanks; so the final version is going to include a pair of temporary stiffeners that fold down and stop this. This would be the moment when they are removed to allow the valancing to take their place.
And onto the boiler. In a departure from normal practise, I am not including a flat etch to be rolled into a boiler – it is relatively difficult to get even a pre-rolled boiler into a neat tube without a visible seam and if you do not have a rolling machine it is effectively impossible to do so. In addition, where boilers have been half etched to create boiler bands I find that the half etched elements that remain are overly delicate. This was something that caught me out a while back when I drilled such and area to take handrail knobs and badly distorted the metal – this kit is still sitting in its box now and I am probably going to have to replace the boiler.
With these problems in mind, I simply used a piece of brass tube from Eileens; easier and much more durable and if I were sratch-building I would not even think of taking a different route. This did still leave the need for some rolled parts, to make the smokebox and I have sought to use another little trick here to make these easier to fit – some tags and eyes. The tags are strips of half etching that pass through the eyes and then tugged back. This can’t impart a curve into the metal but does allow the parts to be pulled tight and makes it easier to solder into place without much of lip. Mind you, they were a tad short and will be lengthened slightly in the production run.
A second additional laminate is then needed to form the outside of the smokebox and down onto the saddle.
I did find another little error when it came to the front of the smokebox. Whilst the diameter for the front that I had drawn had allowed for the thickness of the two laminates, when you fit these there is also a layer of solder between them and whilst this ought not be that thick, it was just enough to make the fronts too small. In the production run, I will deliberately make this a tad too big as it is easy enough to file it back but much more difficult to add the missing metal (I didn’t, I just made a fresh one from sheet metal). The smokebox door is not mine, the door from the Lochgorm Models Loch is the right size judging by the photographs (note the drawing in the old man’s book has it being smaller but this does not match the photos, so I ignored it in this respect – sorry Dad!).
The downside of using tube as a boiler is that boiler bands need to be considered. I have provided these in the kit (again using the strap and eye technique). I chose to fit them on this kit although in practise I think any metal boiler band is too thick and would probably have done it with a transfer sheet if this was not a test build (done prior to painting, the thickness of the transfer is enough to show through the paint on what will be a single colour to the boiler).
Only the top of the boiler is visible after the first ring and a bit, so can be cut away to leave lots of room for the motor, weighting and DCC chip. I may try and fit this with sound, so who can give a view on what it might have sounded like – a jinty is my favoured guess?
Scrap Tank Test Build 5 – Getting on with the Chassis
With the basic chassis made, it is essential to fit the nuts to secure the body to the chassis as both of these will be concealed with later work. So a quick test fit looks like this and we can get onto the next bit, the coupling rods. 
As is not uncommon, these are made from a pair of layers of brass laminated together. You can see that the outer layer is half etched for much of its length, with the full depth only being present at the bosses. I have also sought to make it easier to build these by including them in a folding jig – the folding is underway in the bottom portion of the view. The logic of the jig, indeed the whole kit, is to make a really smoothly running chassis much easier to make. Modern CAD and computer operated phototool creation techniques by the etchers means that it is possible to easily draw and then etch such that each dimension is faithfully repeated on the product. Thus, it is possible to be confident that the wheelbase will be repeated exactly on each side of the frames and also on the coupling rods. However, this accuracy is completely lost if the user has to laminate the two parts together by hand; it is not possible to get them superimposed on each other exactly or repetitively so the spacings of the crankpin holes will change. The jig overcomes this as the fold line is so long that there can not be any twist as it folds, so the two parts will meet consistently and accurately. 
It is true that there remain two areas of variability. The first is that the degree of etching will not be exact on every occasion so the holes will be slightly bigger or smaller on each occasion. This can be easily overcome by making all critical holes a tiny bit too small and then opening the holes up with a ream (not a file, reams will open up a hole consistently). The second problem is that a fold is not always consistent on a fold line so the jig can protect against twisting but might not necessarily put the two laminates directly on top of each other. However, the important point is is that they will be correct horizontally, any error can only crop up vertically. Thus, when the crankpin whole is opened up, it is possible that it will move vertically slightly but this will not change the dimension between the holes so the critical dimensions should be retained perfectly.
The above is all true in theory but in practise there was an almighty cock up in my artwork; so I was deprived of finding out. A total case of designer error and when this is yourself, there is no one else to blame………………. 
………..I made one of the coupling rods no less than 8mm too long – doh! I have no idea how, but it needed chopping; so it was back to the old fashioned way of making coupling rods despite my high ideals! Fortunately, as they were laminated, it is possible to stagger the cut to make the splice – essentially the same technique as Alan Gibson’s variable length coupling rods. Anyway, after the cutting and splicing, I did get a sweetly running chassis and this is what it looks like. The unusually large wheels for a shunting loco are already making their presence felt! 
The chassis is created around CSB’s; continuous springy beams. A spring wire is anchored to the chassis at four points per side (for an 0-6-0) and at the centre of each hornblock. Thus each hornblock is supported on either side and can “bounce” on the spring. However, the clever thing about CSBs is that when a hornblock is depressed, not only does the spring wire flex a bit as suspension, but it also rocks on the anchors so the adjacent wheels push downwards a bit to equalise out some of the deflection. It produces a really smooth chassis and, if it is conceived at the design stage, I think is actually rather easier to both design and build than traditional compensation. This is a close up of a pair of hornblocks and a pair of the anchor points (the other is hiding behind the frame spacer on the right). Also worthy of note is the colour coding of the hornblocks; to enable them to be reinstated in the same hornguide each time. This is probably unnecessary with modern (and therefore consistent) hornblocks and the accuracy of the etching I have noted but old habits die hard! 
Scrap Tank Test Build – Part 3; Cab Inner & Roof
I have designed the cab roof and much of the cab interior to be a separate assembly, that can be secured by a series of screws. As can be seen below, there are two screws at the rear that locate into a tool box that sits on where the bunker projects into the rear of the cab. As the screws are somewhat lost in the bunker, I have come up with a little dodge where these are retained by an initial nut that traps them in place but still allows them to twist and thus engage in the cab roof assembly. The other screw comes through the top of the boiler, just inside the backhead.
The roof is connected to these fixing points with some inner liners to the cabs which can be seen here; the nuts for the rear piece are hidden in the toolbox and to the front within the false top to the boiler. You can just rebate in the rear spectacle plate that will take the glazing material.
The actual cab roof has a double skin, to aid its strength, include the lamp irons and also to assist with locating it on the cab. The outer skin includes the ribs that appear on the real roof, including a grove to allow brass wire to be used to form the seam to this. To the perimeter of this, there is a valance.
And this is what it looks like on. I find that I just can’t make roofs sufficiently well to sit perfectly on the body and nothing shouts “its a model” more than gaps where there shouldn’t be any – be this under buildings, roofs or between parts that have to be joined to structurally stand up! This is my solution, which I have used on other builds that I have done but it is so much easier when it is designed in.
Early Pattern Lookouts for Dia 38 HR Goods Brake
I have been doing more with the Scrap Tank, but I haven’t managed to take any pictures due to needing flippers outside yesterday. So instead, lets see something else that was on the test etch that I have recently had returned.
This is the early style lookout for the dia 12 Highland Goods Brake. As originally built these lookouts formed by a single slot to the centre of the roof and were fully glazed to the front and back. In use guards complained that they caught their heads on the lip of the roof as they climbed in. To overcome this, many of the vans were rebuilt to include ramped approaches to the centre of the lookout were incorporated, to become what was arguably the signature feature of the Highland’s rolling stock.
Microrail produced a kit for this van 30+ years ago and this included the latter style of lookout. I had a pair of these kits and ended up acquiring a third one and I felt I really could not have another one just like the first two! So I had an inspiration and thought it would be fun to make the early pattern lookout. The old man’s book came out and a scan of the drawing loaded up into the CAD machine. From here it was a relatively simple exercise to draw up the difficult bits, the glazed screens, and the more simple roof.
The components went together easily and do give a very different feel to the Microrail kit as intended. I also made a number of other adjustments, to the footboards and also the panelling, to make the model both different and authentic. The latter, the beaded panelling, is a right pain in the whatsit and took much longer than any other element of the assembly – so don’t to it unless really want to! And this is what it looks like next to the kit as originally intended, with the later style lookout.
I will be making these available via the Miscellany Models site shortly, when I have done enough of the other elements I am working on to do a production run. In the meantime, I do have a pair of very slight seconds (there is a tiny bit of over etching – almost impossible to see, the pictures of my vehicle have the same problem). These are available for the price of the metal; say £2.50, plus postage (which won’t be much). Ordering is via here: http://miscellanymodels.com
And the real thing looks like this:
(C) Bill Steel
