Author Topic: The "Plastic Bugger" .... aka GRS kit for GWR 8750 Pannier.  (Read 7098 times)

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Offline John Candy

Have continued working on the cab which has proven to be a bit of a "bugger", not least because of difficulty accessing the interior to measure and fix the detailing!

The exterior: Note the reshaping of the floor at the cab entrance, the addition of door handles and top edge beading to the doors. The doors were set crooked in the casting and were slit along  the offending edges and glued back parallel with the entrance apertures.

The interior : This took a lot of sorting out....largely the result of being supplied with a bag containing a large quantity of small castings which had no means of identification and no instructions on assembly.
A whole day was spent just trawling through books and the web to find close-up views of the cab interior and identifying the parts.
The best advice I can give is to ignore the photos which accompany the instructions (they appear to be taken using  a different, brass, kit ) and use photos from preserved 57XX locos.

A major trap (literal pitfall) awaiting you, is the location cast into the floor of the cab to locate the reverser.  DON'T do as I did and plant the reverser into it. Fortunately, I immediately went on to fit the rear axle springs and positioned the cab floor into the cab shell to check the height : It was immediately obvious that the lever was sitting far too low and was not far enough out from the centre line. Luckily, the superglue had not fully cured and I was able to remove the lever rachet from the "pit" without damage to either part. The "pit" was then filled with Isopon and the reverser re-positioned, a "casing" (visible in photos) also being added to the inboard side of the rachet. Note the position of the smaller lever adjacent to the rachet and is in a very different position to that shown in the instructions.

The Running Plate : WARNING
The hanging bars (a.k.a. valances) are steel angle (brass on the model) but note that the flange fixed to the running plate faces outwards  NOT inwards on 57XX locos.
The instructions tell you to locate "about 4mm" in from the edge of the running plate but that should refer to the outer edge of the fixing flange : The vertical bars should be a scale 6 inches (6.75mm) inset from the edge. If you fit as per instructions, then the drop end plates will be almost flush with the buffer plank ends, instead of being noticeably inset.

Decision time!
The fixing flange on the brass etch is far wider than scale, so fitting the "right way" round will not work. The running plate in the kit is steel which is over scale (of only need to look at the bent corners of running plates in old photos of these locos to see why) so adding to the visible thickness is probably not wise. The only sensible method is to have the flange facing inwards but the vertical bar inset by the correct distance....  6.75mm NOT "about 4mm"!

There will be ramifications when you come to fit the steps to the running plate and possibly with other fittings (e.g. the sand boxes) but they can be dealt with when that stage has been reached.

Photos illustrating some of the cab and boiler mods are attached and fuller explanations will follow.


My fellow Members, ask not what your Society can do for you, ask what you can do for your Society.

Offline John Candy

The second of my GRS 8750 class kits (being completed in parallel with 4667) is to be built as 5786 in "as built" condition.

The most obvious difference between the early and late Lots is the cab but there are several other differences (many of which were erased by later modification to match the newer locos.).

1) As built, none of the pre-1942 locos were fitted with the external top-feed casing.
2) There were no steps fitted to the sides of the bunker.
3) The handrail on the leading edge of the cab opening was not fitted to the side sheet but to the extended end of the cab cut-out beading.
4) Cab doors and sliding shutters were not fitted.
5) The injector arrangement differs from the locos with the top-feed casing.
6) The "contractor-built" locos were fitted with riveted tanks (the Swindon-built tanks were welded).
7) The lubricators for the middle axle bearings were plainly visible ahead of the splasher.
8 ) The tank fillers (including those on the early Lots of locos of the 8750 type) were the older circular pattern, not the more modern oval type as fitted to the kit.
9) The tank saddle braces (the bits of inverted T-section which lie across the boiler and firebox on the kit) were flat section and not "T" .
10) The whistles were not fitted with shields and were operated by direct cable linkage to the whistle and not by internal steam valves.
11) The brake hangers and blocks are of an earlier pattern, quite different to the later (forged steel)  pattern as supplied with the kit.
12) Position of the lamp irons which carry the spare lamps : Original Swindon drawing (and photos of early locos in original condition) show two lamp irons by front of the leading splasher on LHS. Photos of locos built in late 1930's and after, show two lamp irons on LHS between tool box and injector. In photos taken later, some locos (with either cab type) have three lamp irons in either of the positions previously mentioned!

That covers most (if not all) the visible differences between early 57XX locos and the later 8750 types but remember that there was a transition period during which 8750 locos (those with the Collett cab)  were built with other features carried over from the earlier design and , similarly, many, but not all, of the earlier locos were gradually "updated" with all or some of the "improved" design details. All eventually received the bunker side steps and cab doors but other updates were "patchy" in their need a dated photo if you want to get it absolutely right!

Reverting to the major surgery, which is the cab replacement, the plan is as follows.
1) Cut (from brass) a new cab front spectacle  plate which stops just below where the tank top corners meet the cab side (dimensioned to fit between new brass cab sides).
2) Cut a cab rear spectacle plate which stops just below the bunker side sheets.
3) Cut two new cabside sheets which are full height at front and include the strip which carries the roof (the cab back is only as thick as the separate rear spectacle plate).
4) Cut a new roof from brass.
5) Cut away the roof, upper sections of cab (front and rear) and the entire forward section of the cab sides (reprofile the top forward corners of the bunker to match profile of new cab entrance).
6) "Slim down" the remaining (lower) section of resin cab front, which will attach to the boiler/tank unit, so the new brass cab sides sit at correct overall width.

Detailing :
Roof : Transverse sliding vent (brass sheet and angle) and rain strips (brass angle).
Cabsides: Rivets ;  beading around opening from brass strip (including extension to locate leading handrail).
Cab rear : Spectacle bars, rivets, coal doors and brake handle recess.
Cab front : Spectacle surround, rivets, holes for whistle controls.
Bunker (resin retained with new profile) : Substitute half-round beading for the flat beading.

Attached photo shows the butchered resin cab and the only parts retained for incorporation into the new cab for 5786.

Livery Note: If you are building a loco with top-feed casing, it would never have been lettered "Great Western" (except preserved examples now living in a theme park world!) since the "GWR" branding (superseding the "shirtbutton" art deco totem) was in use by 1942, when the first locos were fitted. The 8750 locos built from 1942 onwards, until end of the war, were turned out in plain black livery, not green.

« Last Edit: Jan 07 2018 10:25 by John Candy »
My fellow Members, ask not what your Society can do for you, ask what you can do for your Society.

Offline John Candy

WARNING : If you have already built your 57XX/8750 kit...and are perfectly happy with is the time to stop reading!!


Ever since I started working on this kit I have had that "something isn't quite right" feeling.... but as with the LMS 4F kit which I built a few years ago, I couldn't put my finger on it unti I got well into the build.

Well, when I started measuring up for the templates to mark out the replacement brass cab for 5786, it hit me. What isn't right and alters the "demeanour" of the model loco, is the curvature of the shoulders of the pannier tanks. The radius of all four tank shoulders is way too tight, not that far off being "square" and it alters the whole appearance of the loco.

It will have to be altered but the thickness of the resin casting is a limitation as the parts stand : It may be necessary to add material to the inner surfaces of the tank castings to provide sufficient depth to "round off" the shoulders to an acceptable profile.

It has to be done..... for me it cannot remain "as is", the whole thing looks too "boxy".
As soon as I have finished cutting the parts for the new cab, I will deal with the tanks.

More soon.

My fellow Members, ask not what your Society can do for you, ask what you can do for your Society.

Offline cabbage

There IS a reason I build almost everything...



Offline John Candy

Indeed........ the two Panniers will definitely be my last GRS kits ....... "on the stocks" are brass GNR and GCR locos (scratchbuilt) plus a trio of (superior) LNWR brass etched locos...... from a well-known source.

With interest, I read the following in another model rail forum the other day .... if the writer is also a member of this forum, perhaps he will hold up his hand?

<quote> I built a 8750 ex G.W.R. Pannier in Gauge 3 as a commission for someone. The idea was to use a Garden rail kit as a starting point but to produce something with at least as much detail as you'd expect in a good 7mm model. I'm not sure what percentage of the kit was used in the end, but I did replace quite a few things  with better scratch built items. The kit was a real mixed bag which reflected the different attitude of the garden rail community (of the time) which was very different to 'indoor' scale modellers. </quote>

I have the feeling, not a lot has changed, at least in certain quarters.


My fellow Members, ask not what your Society can do for you, ask what you can do for your Society.

Offline John Candy

The good news was possible to re-profile the shoulders of the pannier tanks without breaking through the castings.

To do the eight shoulders (two locos) took a couple of hours and left me surrounded by a heap of resin shavings, etc. First I shaved with a knife, then used a diamond file to take off the "edges" and finally smoothed with fine emery.

It was not easy taking photos in artificial light to show the difference it has made : The end profile is more rounded but the biggest difference is the side elevation view : The light now reflecting off the curved shoulders has removed the "slab-sided" appearance which just didn't look right.

The new cab for 5786 is almost complete and then both the bodies will be detailed.


My fellow Members, ask not what your Society can do for you, ask what you can do for your Society.

Offline John Candy

A Tale (or Tails) of Two Panniers!

5786 has a new brass cab while 4667 has a modified resin cab.
Apart from the immediately obvious, the differences between the two types (as originally built) are the lack of bunker side steps on 5786 and the arrangement of the cab entrance leading  hand rail, which is not attached to the cab side but stands in the cab entrance, supported at the upper end by an extension of the cab cutout beading.

One "odd" feature of the rear cab sheet of the early 57XX locos is the way in which the brake handle recess was positioned, such that the top LHS corner had to be "cropped" to avoid the rim of the spectacle! I have to ask ,"Why?"!

5786 still requires the bunker beading and handrails, etc. to be added to the sole remaining section of resin casting. The cab front is 100% brass (I decided against retaining the lower resin section, as mentioned in an earlier post). The brass used is 0.8mm thick and the rivets were produced by drilling to half the thickness of the brass (from the inside) and then using the Metalsmiths rivet press (the drilling removes any tendency for the area around the pressed rivets to distort, in the same manner as half-etching does with kits of thinner material). 

One point to note (and an error I have observed on GRS made up kits in their publicity photos) is that the bunker side  steps were on the LHS ONLY.....not both sides of the bunker. All locos were eventually fitted with these steps even where not an original build feature (similarly, all the cab hand rails were eventually altered to correspond to the later type).

Next to roll and detail the roof, which should be a fairly quick task.

More soon,

P.S. I should have mentioned that the brake handle recesses were made from aluminium sheet.... the castings in the GRS kit are way too small.
My fellow Members, ask not what your Society can do for you, ask what you can do for your Society.

Offline John Candy

The new brass cab for 5786 has been completed (still needs a thorough clean, as can be seen from photos.) and as soon as the beading,  lamp irons and fire iron  brackets have been fitted to the bunker section and the the boiler backhead fitted to the cab front, the two parts can be painted and assembled.

The cab backplate is fitted to the bunker coal plate by two 8BA screws/nuts and the cab front will be fitted into the rear of the tank casting.

More soon.

My fellow Members, ask not what your Society can do for you, ask what you can do for your Society.

Offline hornbeam

Hi Jon,

What size of iron do you use? Also when attaching beading what’s your method, do you tin it first? I’m looking at building my first etch brass kit so keen to get some tips thank you,


Offline John Candy

Hi Simon,

I used a 100W Antex which made light work of the 0.8mm brass components (which is quite a bit thicker than the average etched kit).

I tin the beading and the edges to which it is being attached and use either the iron or RSU (latter if beading needs to be pressed to stay flat/in contact during process .... also useful if attaching details in close proximity to an earlier joint).

My fellow Members, ask not what your Society can do for you, ask what you can do for your Society.

Offline John Candy

Re: The "Plastic Bugger" .... 57 Varieties (GWR not Heinz).
« Reply #25 on: Jan 20 2019 10:54 »
As part of a concerted effort to clear my workspace of unfinished GRS kit models (so I can get on with the more interesting projects), the pair of 57XX panniers have taken centre stage. They now need just a few hours work to complete them. I selected 5786 and 4667 to form the basis of my models.

To assist anyone engaged in detailing one of these locos, the photos below show the differences in tank detailing between the two (5786 being Swindon-built, 1930 example and 4667 one of the later modernised design built 1943, both completed in "as-built" condition.

Although all mechanically similar and lumped together as the 57XX class, there were (as one might expect among the largest single class of loco ever built) a multitude of detail variations and permutations thereof.
Detailing is not clear-cut between the original and modernised designs, there being many Churchward-style features (e.g. Turnkey /screw-down tank fillers and a lack of bunker steps) which were included in the early Lots of the modernised 8750 series locos. The prominent top feed casings only appeared from 1940 onwards and were retro-fitted to many but by no means all, the earlier locos over time.

The two most obvious differences in my models I have mentioned above (top feed and tank fillers) but other subtle differences are the cross-section profile of the tank stays (flat on 5786 and T-section on 4667) and the type of steps fitted to the tank front.

If you want to simplify your own kit-build, I would suggest choosing a pre-1940 loco with the modernised Collett cab and the lever-type tank fillers and this will involve removal of the top-feed casing but considerably simplifies other detailing. You could also remove the modern tank fillers and fit the older turnkey type, since many early locos in the 8750 number series retained the older fittings.....check photos.

Whichever type of loco you select, it is worth "rounding-off" all four "shoulders" on the tanks. They are far too "sharp" on the resin casting as supplied. Filing/sanding them to a far more rounded profile "softens" the lighting effect on the tank sides and alters the demeanour of the loco.

If you do retain the top-feed, the pipework was enclosed in a steel pressing where it runs down the tank sides (just ahead of the cab) to the injectors on the running plate. The kit provide a section of styrene plastic tube to represent this but it is not only incorrect in cross section but you will have problems trying to bend it to match curvature of the tank shoulders..... it will simply snap..... although heating may help but I didn't bother. On 4667, I took a length of thick wall copper tube (3mm dia.) and bent it to match the curvature. Inserting a length of 13A ring main copper earth wire into the ends of the tube will prevent it from losing its circular shape and the wire can be pulled out after shaping. The face which is to be glued to the tank sides was filed flat, as were the sides, leaving just the front face rounded. At the bottom, I left a section of wire as a spigot the join to the injectors, while at the top, the core of the tube will accept the plastic-coated wire (supplied with the kit for the pipework) as a force-fit.

Photos of 5786

Photos of 4667

My fellow Members, ask not what your Society can do for you, ask what you can do for your Society.

Offline John Candy

57XX Variety : Cab Detail Variations.

Photos showing cab differences between early-build locos (as originally built) and later locos with the improved Collett cab.

Points to note :
Bunker side steps and accompanying grab rail (fitted only to LHS of loco).
Vertical cab entrance handrails.
Cab door on later locos.
Position of handbrake housing.
Number of fire iron rest brackets (early locos had just three, with middle one offset to left of centre).

Always check a photo of your chosen loco, since "improvements" to minor fittings were gradually introduced and did not coincide with the change to the new design of cab (i.e. some early locos with the new cabs lacked some of the improvements when new). Older locos were, over a long period, retro-fitted with updated fittings.

My fellow Members, ask not what your Society can do for you, ask what you can do for your Society.

Offline John Candy

Re: The "Plastic Bugger" .... More holes than Gouda cheese!
« Reply #27 on: Feb 03 2019 20:09 »
More holes than Gouda cheese!

You look at the running plate of your 57XX (as supplied with the GRS kit of the 8750 variant) and are grateful that the majority of holes have been laser cut in the steel, leaving just the lamp iron and sanding lever cross-shaft rivets to be drilled. It's an illusion..... a lot of the holes are IN THE WRONG PLACES!
There are 8 holes which need to be filled and re-positioned, in addition to the aforementioned rivet holes to be drilled.

The grab rails by the steps between the leading axles are too close to the edge and too close together, the sanding lever pivots and the holes locating the filler caps are very much displaced from their correct positions.
The photo below shows the redundant holes encircled in red with the newly-drilled holes close by.

Incidentally, the reverser reach rod is neither mentioned in the instructions nor supplied with the kit, so you need to make your own and cut a slot in the running plate to mount the supporting crank.

There is a Swindon GA drawing in GWJ No8 which I have used in constructing these models. Incidentally, one detail variation which I have not seen mentioned anywhere is the position of the step between the leading axles. The Swindon drawing shows it considerably off-set towards the leading axle and photos of Swindon-built locos show it thus. However, photos of the contractor-built locos show it more centrally positioned between the leading axles. Ex-works (broadside) photos in photographic grey livery of Nos. 5700 and 6743 clearly show this. Of the "early cab" design, only Nos. 5750 to 5799 were built at Swindon.

If "Easy Build" suggests to you that all that will be required is superglue, a selection of small twist drills, screwdrivers and spanners plus some filler and emery paper , then you are living on a different planet to GRS! "Easy Build" is not a description any reasonable person would apply to this kit. You need only look back through this thread to appreciate that comment : Cutting the end off the steel motor shaft, and using a Forstner bit to drill out castings to provide clearance for the flywheel, cutting away the rear end of the tank casting to provide clearance for the motor are just a few of the traumatic moments an inexperienced builder will face.

Thankfully, the kit it is no longer being produced (the moulds are worn out) but I understand that a replacement (modified form) kit is being considered. I only hope that all my comments on the "Plastic Bugger" (not a tag which I bestowed upon the kit but one which is entirely appropriate) are taken on board if a new kit is eventually to be produced.

My fellow Members, ask not what your Society can do for you, ask what you can do for your Society.

Offline John Candy

Re: The "Plastic Bugger" .... Coupling Rod dilemma.
« Reply #28 on: Feb 06 2019 12:41 »
Coupling Rod dilemma.

One unsatisfactory aspect of the 57XX/8750 Pannier kits is the coupling rods. ALL 57XX pannier tanks had fish-belly pattern rods but the kit is supplied with parallel rods. This problem had been gnawing at me for some time and I was almost resigned to leaving them as they were.

I decided in the end to rectify by applying nickel silver overlays to the steel rods. As it happens, the task was made simpler when I remembered that I had discarded the fish-belly rods from the Dean Goods kit in favour of steel rods.

The Dean Goods rods (as supplied with the original batch of kits) were of a tri-fold nickel silver arrangement which I intensely disliked and had replaced with steel rods of the fluted parallel type (as were fitted to the final Lot of Dean Goods locos).

Fortunately, the Dean Goods has the same wheelbase as the 57XX and I was able to use the leftover parts (with some modification) and soldered them over the 57XX steel rods without removing from the chassis (using the monster 175W iron).

Before and after photos.

My fellow Members, ask not what your Society can do for you, ask what you can do for your Society.

Offline John Candy

I have reached the stage where I am just adding the final few cosmetic items and thought it would be plain sailing from here on in.  I had overlooked the provenance of this kit .... it still had a few nasty surprises up its sleeve!

The etch for the sanding lever gear (which is very prominent above the running plate on these locos) looked very good and I confidently detached and cleaned up the parts. The cross-shaft provided was much larger in diameter (around 2.5mm) than the mounting holes in the etches but it would not be possible to open out the etched holes.... they were too narrow to accommodate a 2.5mm hole.

Not a great problem, I simply selected a slightly smaller diameter rod from my stock box and used that. However, the distraction of the shaft diameter caused me to forget to check the Swindon GA drawing and photos and I merrily went ahead and soldered up the sanding gear. It was only after that I then checked the drawing and found the primary lever to be the wrong shape! Bugger! It took almost an hour of fiddly work to de-solder the gear from both locos, reshape the lever and refit.

This is just one more "defect" needed to be added to quite a long list of remedies necessary to be applied to this "Easy Build" kit.

Photos below show lever shape before (top) and after reshaping (below).

My fellow Members, ask not what your Society can do for you, ask what you can do for your Society.