Atlantic's works: Portable layout update

[Atlantic 3279]

There's no need to rush off messages to remind me, as I have a list of all of those who asked about possible J6 and K2 resin parts, but patience is at last likely to be rewarded as I have completed my current round of casting of "standard" parts for these two loco types. I haven't done any original taller GN cabs for the K2s yet, nor any of the still experimental resin chassis blocks for the J6s, but as the pictures below will tend to confirm I have nine otherwise "as complete as they will be" sets of parts for each loco type. I've batch produced each part rather than making one complete set at a time, because the different techniques for the successful filling of each mould would simply have been too confusing had I tried to keep switching from mould to mould. I still have to inspect closely and pack into sets the J6 fittings before I can start sending any of these off to anybody, and should tall GN K2 cabs be wanted or J6 chassis blocks these will have to be cast as and when possible. I believe I've cast enough parts to cover the number of requests / enquiries I've already had, and with the number of other things I'm also trying to accomplish it is very unlikely that I'll be able to return to the casting of further full sets of parts for these locos for quite some time. I'll endeavour to be in touch individually in the near future with those who previously stated an interest. If any sets of parts remain after I've offered them to those on my list, I may be able to supply them to others, but I have no time at present to respond to fresh enquiries or start building up a "reserve list" so if you have only just noticed these items please await further news on here before sending me any requests.

A word regarding the tenders: Those presently paired with the K2 bodies have round water filler and unequally divided wheelbase side frames. Those paired with the J6 bodies have rectangular water filler and equally divided wheelbase side frames. The same inner chassis is provided with both, marked for unequally divided wheelbase but with enough material to allow drilling at equal centres instead if desired. Supply of "the other" type of tender with any loco body will only be possible if modellers' wishes facilitate swaps.

[52D]

Doncaster has migrated to Lincolnshire.

[manna]

G'day Gents

Not content with one or two in a class, he gone for 'Fleets' of 'em.

With the 'Pound' going down the gurgler, want to swop, a block of butter for a couple of chimney's, half a side of lamb for a K2

manna

[S.A.C. Martin]

Brilliant work Graeme! Looking forward to getting my hands on the kits. Nearly finished the V2s you supplied me way back when so my K2 and J6 should be complete by 2019

[Atlantic 3279]

Here are some notes and images in order to show exactly what points may need to be addressed in preparing the J6, K2 loco and the GN tender castings for use. I've only used the J6 loco body castings as specific examples but similar considerations apply to the K2 parts and the tenders. As will be noticeable, many of the parts have few or no features that register or engage with adjacent parts to control final relative positions, so when it comes to assembly it is sensible to refer to a decent scale drawing and to photographs of actual locos in order to get things in just the right places.

The flat cab fronts are formed against a flat surface at the top of the resin layer in the mould. Tiny air bubbles entrained in the resin mixture inevitably end up in the surface layer of the resin and when this is cleaned back to final size with files or abrasives the bubbles are broken, leaving tiny pits in the surface. Fine filler needs to be pressed or otherwise introduced into these before further rubbing down if the eventual painted surface is to be free of defects.

Although the moulding box for the boiler was "cunningly" tilted when the moulding rubber was poured in, bubbles in the rubber still managed to cling to the smokebox front and the valve front cover plates below the smokebox. The resin boilers all emerge from the mould with a combination of tiny hard beads of resin and small pits in these front surfaces. The beads of resin are easily broken off with either finger nail or the tip of slim metal tool. The pits again need a little smooth filler, best pressed in with fairly narrow, flat ended tool such as a jeweller's screwdriver. Care is needed to avoid burying the two raised circular valve front covers with excessive amounts of filler, and to avoid digging into these with any metal tools used for cleaning up.

Some of the J6 boilers have a thicker wall of resin on one side than they do on the other, owing to the core piece in the mould failing to centre exactly. In the image I've failed away some of the excess of material inside one half of the smokebox, hence the coarse file marks visible in there. There is no problem of excessively thin or weak areas in the thinner side. Firebox sides are equal enough, and thin enough in all cases to allow a motor to sit in the firebox. If the motor needs to go forward inside the boiler barrel then either the deliberate selection of a boiler with nice equal side thicknesses is called for, or some filing out will be necessary.

The smokebox doors are cast in an open mould, hence there's a meniscus on the back surface. They look as if the raised lip around the edge of that meniscus ought to plug into the opening in the smokebox front. This may just be posible for the K2s if the hole in the smokebox front is filed out a little, but fitting them into the J6 boiler fronts in that way would be a long, tedious job. It is much quicker to rub the back of the smokebox door moulding on a large flat file or abrasive sheet to flatten it off entirely, taking care to stop before any damage to the outer ring around the door occurs. The flat backed moulding can then be positioned exactly as desired on the smokebox front and glued in place - but only when loco construction has reached the stage at which access to the interior of the boiler is no longer required......

The backheads also have an open-mould meniscus and need to be filed flat to sit neatly against the cab front. It's very much a generic LNER narrow-firebox backhead, so the lower parts also need trimming/shaping to miss any splashers that protrude into the lower cab space and to make the backhead sit at the right height. The diameter of the upper part is about right for the K2 but the edges will need filing back somewhat to suit the J6 properly.

Buffers and Ross Pop valves (the latter with wire inserts for strength) come out of the mould in a sheet of flash. They will need careful trimming-round to remove the flash and the seam lines before fitting to the model if best appearance is to be achieved. I did even try to produce whistles in the same manner as the Ross Pops but the results have not so far been encouraging!

The brake shoes, middle steps and the front valve spindle guides are also on a sheet of flash and need trimming free of same. The thick brass wire insert in the valve spindle guides actually forms the whole thickness of the front section of the guide, the resin forming only the thicker rear parts of each guide. There's plenty of rearward extension of the brass insert to act as a strong locating pin when fitted into a suitable hole drilled into the centre of each circular valve front cover.

They are perilously fragile but as an experiment / test of skill I've put a reversing lever moulding in with each set of J6 fittings. I haven't bothered with the K2s as it was tricky enough to produce just a few of these moudings successfully. In some cases the sheet of flash around them is thicker than I would have liked. Trimming the flash away thoroughly without snapping the moulding, especially the slender top parts, will require care and patience. The height as moulded is probably too great so the base will need cropping off before the lever will suit its home in the cab.

Just in case a mounting for an NEM coupling pocket is required (one of those rectangular-sleeve things with the wedge-shaped tail) these little resin blocks can be filed down at the sides so as to fit neatly between the frames and screwed to a frame stretcher above. Filing of the top face of the mounting block or the addition of spacer pieces will be required to set the desired coupling height. I've put one of these with each K2 body, each J6 body and each tender.

[manna]

G'day Gents

Some gorgeous castings, there Graeme, considering the size of them.

manna

[Atlantic 3279]

Thanks. If everybody agrees, that's wonderful news. Either way, I have been honest and open about the imperfections in the castings.

[S.A.C. Martin]

Looks fine to me - never been afraid of filling then filing anything in model railways. Looking forward to it!

[Atlantic 3279]

Although the question has actually cropped up in a private message it seems to me to make most sense to respond on here with a reminder of the chassis options for those resin K2 and J6 bodies, as I see them:

K2

My original model, the master for the mould, was developed to fit some Bachmann split-polarity V3 chassis units that I had. In order to use those, the rear end of the chassis block and keeper plate have to be sawn off aft of the useful screw holes that sit under the cab floor. If you want the leading pony truck in exactly the right place and looking right you have to carve that around too, but it can be made to at least behave itself if you leave it where it is and you are happy to just trim the cut-outs for the wheels under the front of the body. The cylinders don't look correct as they are, and the slide bars, crossheads and motion bracket are wrong too. In order to even fit the body onto the chassis, the front projection of each valve cylinder and valve guide must be cut off. To make the cylinders look better, a wrapper is needed to make them fatter and to make them meet the running plate edges correctly. New slide bars and a supporting downward extension of the rudimentary moulded plastic motion bracket can be made if you have some suitable nickel silver strip or similar. I used wire stubs soldered into the motion bracket extensions and in turn super-glued to the plastic moulding in order to give my modifications at least some strength. My new crossheads came from the Comet range, via Wizard models. I had to solder on the necessary drop link to carry the Walschaerts valve gear. I haven't written full "instructions" for use of a V3 chassis nor have I the opportunity to do so. Most of the method is apparent if you can find the relevant previous pages of this thread.

I haven't tried such a chassis so I cannot comment of how much is involved and how to do it, but a brief look at the relationship to the K2 resin body did suggest that a Bachmann K3 chassis ought to be useable too, but apart from the body not having been designed to fit such a chassis, the cylinders / motion are no more correct for the K2 than are those on the V3 chassis. The coupled wheels although of a finer type than the V3 offering and on solid metal axles are under true size for a K2.

The SE Finecast K3 chassis may also be useable, but the cylinders and the same parts of the motion as above will again need to be altered.

It is not confirmed but a remark on here a page or two back from a person with the right connections indicated that London Road Models might be prepared to supply K2 chassis parts. Anybody interest would have to make their own enquiries.

J6

My own models have made use of the experimental resin chassis blocks that I produced. I don't have a full description of method to offer, but in summary: Brass axle bearings were inserted after drilling and filing out the well-dimpled indications of axle positions in the resin casting. This required knowledge and use of a means of setting the spacing, the levels and the squareness of the axles correctly before securing the bearings. My coupling rods were Gibson, one set may have been a proper 7' 3" + 9' 0" pair, but in two cases I used some Gibson universal ones because I had them sitting around. My nylon gears including the motor worm, and the metal rods on which the gears turn, came in packets of mixed gear sizes from Squires. The chassis is marked in approximately the right places for the metal rods but a certain amount of fiddling around was required in order to achieve smooth, free, quiet gear meshing. The motors I've used are like these http://www.ebay.co.uk/itm/like/12146327 ... 1463278485 with the unwanted end of the armature shaft shortened as necessary and some thrust washers added "cunningly" outside of the bearings to reduce noisy end-to-end movement of the shaft. The motor platform on the chassis can also be drilled differently to take a small Mashima motor. Chassis performance and durability is a case of "so far, so good".

Roy Mears has used the resin chassis block slightly differently in respect of motor and gears, cutting off the moulded motor platform and opening up space between the frames to take a gearbox (High Level?) and fitting a bigger Mashima.

I'm not aware of an RTR chassis that offers correct wheel size, correct wheelbase and which will fit wholly within the J6 body, fouling neither the cab space nor the space beneath the boiler. A Hornby(?) Southern (700 class?) 0-6-0 chassis has been suggested but it appears to me that the bottom of the boiler, which forms part of the chassis, is too low down to neatly suit a J6. I used a cut-down Bachmann K3 unit in my J2 variation but a big chunk of the gear housing shows below the boiler.

Gibson frames may be an option for a home-brewed all metal chassis.

LRM do a J6 of course but I'm not suggesting that you should expect them to offer the chassis parts separately....

[mick b]

Interesting information, thanks Graeme.

[Atlantic 3279]

As life has prevented me so far from returning to the P2 projects, for long promised production of moulds then completion at last of my own "not properly finished models", I don't want to jeopardize availability of motive power for Grantham's appearance at the NEC later this month by starting to mess about with the locos now. I'll try to do that over the winter. Small projects that can be fitted in between life's other demands, picked up and pit down as necessary without losing the thread and without leaving a load of parts and tools lying around will have to be my limit for the moment. Some tinkering with tenders will do for a start. I have another GN Ivatt tender to provide for a J6 that donated its tender to my J2. I also have the LRM later Stirling tender to build so I can put a more typical tender behind my K's J3 (and a half).

The easiest one to tackle first however was tender top swap for my Royal Lancer, a simple renumbering of Hornby's Flying Fox. This loco would be fine with its original Hornby GN tender as a pre-1928 portrayal of Royal Lancer, and I'll be keeping the GN tender top to allow reversion if required, but for appearances on late-thirties Grantham the tender should either be a 1928 corridor type (before July 1937) or a "New Type" 1928 non-corridor post-July '37. Until recently, I had the option of re-using a 1928 NT tender top from a Railroad Cock o' the North model, but the shade of green was slightly different to Royal Lancer, full application of lining and lettering was required, and the top would not have been a direct fit on Lancer's tender underframe. It turned out in any case that Jonathan Weallans had need of such a tender top for another Pacific ID change, so I let him have the work of sorting that out and decided to pursue the corridor-tender option for the time being.

The 1928 corridor option looked a bit easier as I had a fully decorated NRM Scotsman tender top in what looked like the right shade of green. A bit of edge lining along the bottom of one side needed attention, but nothing much really. There were a couple of snags however, as always, and it wasn't just the modern electrification warning flashes that needed cleaning off. The Scotsman tender top as received looked like the standard Hornby imperfect interpretation of a corridor tender (but not the real Scotsman's) in post-preservation condition: very high front plate, (reduced) streamlined fairings, and a funny "shouldered" shape to the rear plate caused by side coping plates "restored" to a non-original shape. I decided I could probably back-date the tender, without wrecking the livery, to portray it as it would have been before appropriation for use behind an A4. I feel sure that the corridor tender behind Royal Lancer up to 1937 would still have been free of the fairings and high plates that were added to suit use behind A4s.

With much care I trimmed back the width of the coping plates over the edges of the coal space with sharp knife, by about 1.5mm, and cut out the rounded front corner pieces entirely. I then filed down the front and read plates of the tender to get as close as I could to the correct height and shape. Some pieces of tinned brass strip were soldered up into the single coal rail that originally sat atop the side corridor. New tank breather pipes were made from tinned 0.9mm brass wire.

In lowering the front plate I've obviously lost the top edge lining, but HMRS should come to the rescue:

I couldn't get right down to what I believe the scale height should be because when it came to the rear plate the height of the corridor connector moulding appears to conflict with this. I did however get rid of the angular shoulders and filed the overall height down a little. as I couldn't lower it fully I did not entirely lose the moulded beading along the top edge - nor the lining. Although that beading is now rather narrow, most of it is hidden by the rail over the corridor connector and it is painted black too making the error hard to spot. You can also see in this picture where I've cleaned off the warning flashes either side of the top of the corridor connector.

That single coal rail and the new breather pipes, shown unpainted. The posts supporting the coal rail of course are planted in tight holes drilled in the corridor top.

Nothing is perfect of course, and as mentioned elsewhere recently, albeit in jest, a non-corridor or GN tender's underframe isn't quite right for a corridor tender. The buffer beam should actually be inset slightly more under the rear of the tank (hardly visible) and the rear steps should have a "dart's flight" or "fantail" shape rather than the rectangular one. The scale coupling of course should also be a drop-head buckeye rather than a hook and screw-link. I'm not messing about with the steps at this stage because I may eventually change the top again for a 1928 NT. The corridor connector conceals the wrong coupling on the buffer beam and the infernal Kadee does look a bit like the necessary buckeye.

Now you have all got proper early-type corridor tender tops behind those "correct" 1928-1937 models of A1s and A3s, haven't you?

[Godred01]

Those changes to the corridor tender look amazing, how hard was it to modify it into 1928 condition?

[Mercator II]

More excellent work Graeme, looking forward to seeing it in a few weeks

Come the new year, and the on set of winter, am sure returning to the casting will happen. I certianly look forward to owning a P2 converstion part, and maybe even finding the time to build it!!!

See u from otherside of the barriers at NEC

[Atlantic 3279]

how hard was it to modify it into 1928 condition?

I have no idea of how to quantify difficulty as it all depends on personal ability to make repeated, gentle, straight, true cuts with a knife blade (rather than forcing the cut in an attempt to get through in one go), ability to file to shape without digging the file in to other parts of the model, and knowing "how" to solder to suit the situation, especially in this case where I did it in close proximity to the plastic with the posts already inserted in the holes, to save having to use another method to match up posts and mounting hole centres - which means having to solder quickly and effectively before the heat spreads.

[drmditch]

Many congratulations on those mouldings, especially the reversing quadrant. Do you mind me asking about the size?
My attempt at this for the J54 (Grantham North Pilot) is much cruder, but it would be interesting to know whether I got the scale anywhere near correct.

Many thanks also for the information on the tender. I have an NRM Scotsman to rework (at some point), so it will be very helpful.

I hope I am still on the list for P2 components, when you hve the time to make them. There is no rush from my point-of-view. My re-built railway is only making slow progress, and I keep getting distracted by building rolling stock!