GRS kit Midland Johnson 1F 0-6-0T

[John Candy]

A Beefier Buffer Sandwich.

The rebuilt buffer beams need to meet two criteria : Firstly, to be the correct depth and width and secondly (more importantly) to be strong enough to take the potential loadings.

I came up with following design to meet both requirements.

The etched (nickel silver) beams have been trimmed to correct depth and then a section of 3/8th x 3/8th x 1/16thick brass angle soldered along the OUTER FACING EDGE of the inner face of the sandwich (see photos).
Next four sections of 8mm x 4mm rectangular brass tube were cut, the same depth as the beam and soldered to the inner face of the same piece. Then the front face etching was soldered to complete the sandwich (clamps were used to hold together while soldering with butane micro torch).

Next (before adding the "ends" to the buffer beam sandwich) the buffers were test fitted. I put the rather "bloated" GRS buffers in the "spares" box and used a modified set of Walsall's LMS buffers, the rims/lips being cut away in the lathe to shorten the guides to make them more "Midland" in appearance.

If you use the WMI buffers, you will have to ream out the holes in the front face of the sandwich to take them. Unlike the GRS buffers, which are retained by a thread/nut, the WMI buffers need to be soldered to the beam.

Next a 1.25mm thick brass sheet offcut was fished out of the "odds and ends" box, a strip 5.6mm wide being cut from it and then rolled to the profile of the buffer beam ends. Four sections were cut to cover the ends of the buffer beams and soldered into place.

Before fitting the buffers, I drilled holes on the buffer beams and the buffer bases for bolts and rivets and (using RSU) soldered the them in place.

The beams were again clamped up while the buffers were soldered, using the butane torch, targeted on the tops of the buffer guides to provide just enough heat to melt the solder around the base of the buffer and not de-solder the rest of the sandwich.

The photos show the stages.

[John Candy]

Coming Together....Slowly!

The main frames were next modified to accept the new buffer beams. The heavy brass angle attached to the beam assemblies required rebates in the frames to accept them.
If you have assembled everything square and to correct dimensions, you will find that the buffer beams are a sliding fit over the frame ends, the result being (that although the buffer beams are soldered to the running plate) all shock impact is transmitted through the frames, avoiding the risk of the running plate buckling in a collision.

Next the steps were assembled and attached. Since the flimsy etched hanging bars(valances) have been replaced by chunky brass angle, the steps need to be reshaped to fit beneath the hanging  bars and not behind (otherwise they will be set back too far from the front edge).
To achieve this (and at same time substantially reinforce the very flimsy step etches) brass sheet was cut to provide backing plates which are soldered inside the angle and the cosmetic steps are then soldered onto the backing so as to butt up to the undersides of the hanging bars (thus reducing the inset). This requires the steps to be modified by shortening and the cab steps need to be re-profiled to the correct curvature (as supplied they are far too “curvy”at the top).

Note that the steps ahead of the tanks were not fitted when built but were a later Midland modification. In LMS days, the corners of the step treads were  often “turned up” as a safety measure but not all locos were so treated.

The chassis is designed to be attached to the body by two 6BA screws. Rather than rely upon the supplied nuts, I prepared two lengths of brass bar, tapped them 6BA and soldered to the top of the running plate. When doing this, measure carefully, otherwise the boiler and bunker units will  not seat properly on the running plate (clearances are VERY tight).




















 

[John Candy]

Detailing Progresses.

The Smokebox Door.
Firstly, the oversize, incorrect and just plain ugly GRS casting went straight into the melting pot (it is the same as that supplied with the 2F kit and that one suffered the same fate)! Fortunately, the Fowler-style replacement doors fitted to the 1F were the same diameter as those on the 2F, so I was able to cast a replacement from the pattern and mould I had made for the 2F a few years ago.



The GRS casting (on the right) compared with my replacement!

When built , the handrails on the engines curved over the smokebox door (as a continuation of the rails on the boiler side) but as the original Johnson smokebox doors were replaced by Deeley and then Fowler designs, the curved handrails were removed and shorter, straight, rails fitted to the smokebox doors. Check your photo as replacement of the door did not necessarily co-incide with the change of handrail shape.

Lamp Irons.
The original Midland style lamp irons were gradually replaced by the LMS type (check photo of your chosen loco. to see which were fitted during the period being modelled). My loco is modelled in the late LMS period (just prior to withdrawal in 1938) so has the modern LMS type.
There are no identifiable lamp iron parts supplied with the kit, so you will have to buy an etch from GRS or make your own.

[John Candy]

Stop ... Think!

Before proceeding any further with assembly, it is worth stopping to consider just how the boiler unit is to be fitted to the running plate and where the wiring is to be routed.
Points to consider are : Where holes are needed for wiring to pass from firebox area to bunker space (some electrical items will need to be in the bunker); how to constrain the wiring so it doesn't interfere with moving parts and, finally, how to fix the boiler unit to the running plate without risking damage to previously soldered parts.
To retain wiring in the boiler/smokebox area, I folded up a few brass brackets/clips and soldered them as shown in photo below. These will guide the wiring from the cell pack, motor and sound speaker down between the frames and (where necessary) under the cab floor to the bunker.
A further clip can be retained by the head of the 6BA screw which runs through the frame spacer beneath the bunker  (attaching the chassis to the running plate) and this can guide wiring up through a hole in the running plate and into the bunker.





Where individual electronic components are fitted will depend upon the system you are employing and space constraints. If you are locating items inside the tanks, it may be worth soldering cable clips in appropriate positions.
It had been my original intention to solder the boiler unit to the running plate but, having considered the risk to existing soldered joints (and difficulty of gaining access for soldering iron to make concealed seams) decided to bolt the two together. To achieve this, a 6BA tapped brass plate was attached to the underside of the smokebox and a hole drilled in the running plate to accept the bolt. The cab front has a brass angle fitted on the lower edge, facing into the cab and drilled/tapped 6BA (again a corresponding hole drilled in the running plate).
If you wish to retain the ability to separate the boiler from the running plate and are building a "full cab" loco (this doesn't apply to open cabs) then you will have to arrange the cab roof to be removeable (mine is soldered on, since I don't foresee any reason to remove the boiler).
Before fitting the roof to a full cab version, remember to fit and paint the boiler backhead and other cab fittings!









Detailing

Reinforcing angles along bottom of tanks and bunker : These are not provided for in the kit  but are represented  on my model by narrow lengths of brass strip.

Ejector : If you are modelling a vacuum-fitted loco, then you will have to fabricate the ejector. It sits on the right hand side and the pipework replaces the handrail which runs from tank front to smokebox.  I soldered mine up from bits of brass and copper wire and tube....a fiddly job but worth the effort.

Injectors (Clack Valves) : As I mentioned previously, the supplied castings have the pipework cranked inwards instead of outwards. I cut away the cast pipework from the valves and drilled the top and bottom parts to accept a stub of 60thou brass wire. I then formed new pipework from copper tube and this was  fitted over the wire stubs and the whole thing (not forgetting to insert  the cast flanges which fit between the valve and boiler)  was “Araldited” in position, taking care that all was square and vertical.

[John Candy]

Fitting the Bunker and Cab.

The final major component to be added is the bunker/cab rear/coal plate unit (assembly described a week or so ago). The cab entrance gap needs to be 22.5mm in width and this is the determining factor when positioning (along with the inset from the edge of the running plate, so as to align with the tank sides).
If your bunker unit is good and square, then it should fit easily within the scribed lines and the rear of the bunker should be parallel with the rear edge of the running plate.

When satisfied, I “tacked” one side of the bunker to the running plate using the micro torch and 179deg. solder paint. Playing the flame on the side of the bunker, just above the seam, until the solder runs ensures that nothing else will come unsoldered. The intense heat is delivered quickly to just where it is needed. In fact a high proportion of the smaller parts have been attached using the torch.
After double checking the alignments, 144deg. solder was run along the vertical seams on the inside of the bunker using the soldering iron which was just small enough to fit into the bunker. The joint was made instantly using a 100W iron. The seams along the base of the bunker were then treated similarly. Next, narrow brass strip was added along the base on the bunker sides (matching that previously added to the tank sides) using the RSU and solder paint. Photographs suggest that the base strip was not continued around the rear of the bunker.

Then to the enclosed cab sides  (if you are modelling a full cab version) : Having already trimmed the side sheets to shorten the leading  vertical edge (see earlier post), it was now necessary to shorten the rear vertical edge. I took 1.5mm off and this resulted in the proportions of the cab sides looking to be “about right” when compared with photos.

It was at this stage that the kit bowled a (hopefully final) “googly” :  The cab front spectacle plate is not symmetrical!  The left hand side is 1mm+ lower than the right side., meaning that the cab side sheet on that side is taller than the cab front. The only solution will be to pack the gap once the roof has been fitted.

That can wait until another day.... I am taking a break for a week, so you will be spared my ramblings for a while!

[John Candy]

After short break, work has restarted on adding the final details.

Tank Stays : As mentioned in an earlier post, the stays provided with the kit are only suitable for the Belpaire  (G5 boiler) rebuilds, which the kit does not provide for!

Using 4mm wide brass strip I cut four 9mm lengths and eight 3mm lengths  and soldered them as shown in the photos. Note that the stays are in different locations to those fitted to the Belpaire rebuilds. Measured from the front of the tanks, they are centred at 25.25mm and 79.25mm.

Lubricators : Those for the centre driving wheel bearings are located on the tank tops between the tank fillers and the boiler, centred over the driving axle. These I filed from brass bar. They are 8mm wide, 4mm in height and 1/8th inch deep (sorry about the mixed units but the brass bar was Imperial size). The filler "lid" is angled towards the front.

Water Tank Control Valves : These were made using wire and tube for the valve stem/flange and a press stud "popper" for the wheel! Position is 10.75mm from cab front and inset 9mm from tank edge.

Next task will be to solder the beading to the cab side openings and tank/bunker tops.

[John Candy]

After a brief diversion to complete refurbishment of a GRS GW autocoach, the 1F has finally been completed (three and one half years after starting)!

The cab is one of a batch which had an elevating ventilator of the pattern fitted to the rebuilt 3F tanks and the "Flatiron" 0-6-4 tanks (as well as some tender locos). Photos. suggest this type of vent appears to have been fitted only to a few 1F locos. fitted with full cabs in 1912 (Nos. 1670, 1672 and 1674 have been identified from photos.), the majority having the sliding vents.

The etched plates are from Guilplates : The Midland "makers" plates remained on 1670 well into the LMS period and,  although the LMS replaced them on many locos with the later style plates,  some Midland originals survived into the 1930s.

I wonder how many of these kits GRS produced?
The only other built example I have seen was the one displayed in their shop......are there "abandoned" part-built examples festering away in dark corners?

[Traininvain]

Graham Pearce has built a very nice model of a GRS Jinty:

https://www.youtube.com/watch?v=cahGfHsYAYU

[John Candy]

Graham Pearce has built a very nice model of a GRS Jinty:

Arghhh.... don't let Alan Marsden hear you refer to the 3F tank as a "Jinty".....LMS enginemen called them "Jockos" ..... the first thing Alan asked when he saw my 3F was, "Do you call them Jinties or Jockos?"!
I replied,"Jockos".

Regards,
John.

[Traininvain]

whetever, it's a nice model - but required a lot of work I hear ...

[John Candy]

Ian,

whatever, it's a nice model - but required a lot of work I hear ...

Yes, it is a kit which needs some effort to make it decent but is a resin model so not too many individual bits.

My account of construction can be read here ...... http://g3forum.org.uk/index.php/topic,1157.0.html

John.

P.S. I see you wrote (back in 2015) following :

« Reply #8 on: March 02, 2015, 08:59:20 AM »


Keep writing 'em John. They are of immense value to all those people who want to build a similar kit.

Full report for the G3 newsletter please.

Many tx

Ian

Did that article get into the Newsletter (indeed, was it ever written)?

[John Candy]

Four of Derby's finest ....... 1F 0-6-0T, 2F 0-6-0, 3F 0-6-0T and 4F 0-6-0.

Have you spotted the interloper?
3F No. 7668 (although a Derby design) was actually built at the L&YR Horwich Works, part of the final batch and the only batch actually built by the LMS (all the others were built by contractors).

The 1F and 2F were built from (now discontinued) etched brass kits from GRS; the 3F and 4F are from GRS resin kits (still available).

The 2F was a pleasure to build, the other three were "pigs"!

[hornbeam]

What was the tender chassis like a n the 2F John? Etched with a inner steel frame?

[John Candy]

Simon,

Yes, it is similar in construction to more recent GRS tender locos (e.g. Dean Goods).

John.