Author Topic: GRS kit Midland Johnson 1F 0-6-0T  (Read 15003 times)

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Offline John Candy

Re: GRS kit Midland Johnson 1F 0-6-0T
« Reply #15 on: Mar 17 2014 19:43 »
Mark,

Thanks for that suggestion, I will investigate to see whether correct size available.
I noted that the grooves which are etched into the underside of the running plate to locate the valances  are asymmetrical on my kit and the angle brass may be an easy way to overcome that problem as well.

Problems with this kit are coming "thick and fast" ..... par for the course!!

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

Offline John Candy

Re: GRS kit Midland Johnson 1F 0-6-0T
« Reply #16 on: Mar 21 2014 14:02 »
After some head scratching, the ashpan is now fitted and is clear of the compensation beams.

Firstly the upper edges of the ashpan etchings (which are nickel silver, as are many of the etchings in this kit) were filed so that the edge was straight but the centre section sits a tad below the mainframes, with just the ends sitting behind the frames.
Next a section of thick brass sheet was cut to a length which spanned the frames and sits in two rebates filed in the tops of the frames.
A 2.5mmm hole was drilled 16mm in from each end of the brass, to accept two lengths of brass rod.

The brass was then soldered to the mainframes using a butane torch (the frames are very thick steel  being about twice the thickness of the frames on other GRS kits I have built).

Next a piece of thin nickel silver sheet was folded to form a spacer, which holds the two sides of the ashpan 47mm apart (the spacer is soldered to the ashpan parts just above the curved sections).

The assembled sides of the ashpan are then placed in the correct position between the frames and a small spot of thick superglue applied to each end where it contacts the frames, to hold it while the next step is undertaken.

Next, two sections of 2.5mm brass rod are cut, such that they fit through the two holes drilled in the brass and sit on the surface of the ashpan spacer (leave about 1mm projecting above the brass plate to assist soldering).

Solder the rods, firstly to the brass top plate and then to the ashpan spacer... I used Carrs 179 solder cream and the butane torch, so that contact was avoided which might otherwise have displaced the ashpan during soldering.

The ashpan is now firmly fixed to the frames but, as a "belts and braces" precaution, I then applied a small amount of Araldite epoxy along the seam where the ashpan contacts the frames.

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

Offline John Candy

Re: GRS kit Midland Johnson 1F 0-6-0T
« Reply #17 on: Mar 22 2014 14:27 »
Now the modifications which keep the compensation beams clear of the ashpan and to ensure the previously rather "sloppy" fit of the pivot does not allow the beams to slip off the hornblocks.

Rectangles cut from 7mm x 2.5mm brass bar have been soldered to the ends of the beams in the areas where the beams contact the hornblocks.

They were then dressed with a file to ensure the profile of the beam ends is maintained.

When the beams are reassembled onto the frames, stainless steel 3mm washers are used to space the beam from the frames and maintain the beams parallel to the frames.

The beams are then adjusted (bending gently) so that they have paper-thickness clearance between the new brass blocks and the frames.

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

Offline John Candy

Re: GRS kit Midland Johnson 1F 0-6-0T
« Reply #18 on: Mar 22 2014 21:43 »
Now for the next step.....or should that be obstacle!

You will at this stage be pleased that you carried out the compensation beam modification in the last section because it now enables you to execute a simple solution to the next (and unexpected) difficulty.

The brake hanger/block assemblies are suspended at the upper end by hex-head bolts.
According to the instructions, these are 8BA and screw into the frames (the bolts being of a length that prevents them intruding into the inner surface of the frames, where they would otherwise obstruct the compensation beams in their original/unmodified form).

Firstly, the bolts included in the kit were 10BA not 8BA and secondly, the frames are drilled for 10BA clearance (and have not been tapped 8BA ..... note the commencement of the kit instructions where the list of tools required does not include an 8BA tap).

This is where you will be glad of that extra clearance provided by the compensation beam modification.

You can use 10BA hex headbolts with nuts on the inside of the frames without fouling the compensation (in fact the 10BA gives better appearance than 8BA which would be over-scale).

You will need longer 10BA bolts than those supplied with kit and they will need to be trimmed to leave just enough thread to hold the nut when inserted through the frames.

This is the method I used, since I have a stock of 10BA hex bolts but no 8BA hex bolts.
If I had 8BA hex bolts, I would have tapped the holes in the frames but not everyone assembling the kit will necessarily own a BA tap and die set.

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

Offline John Candy

Re: GRS kit Midland Johnson 1F 0-6-0T
« Reply #19 on: Mar 23 2014 15:35 »
Continuing with the brake rigging assembly, we are now in "uncharted territory" so far as the instructions are concerned!

The initial stage is explained; you attach the pull rods to the lower end of the brake hangers, using some brass tubular spacers and 10BA nuts, attached to the threaded ends of some very nice turned steel cross shafts.
You will have to open out the bore in the spacers to provide clearance for the 10BA threads (no warning of this in the instructions, I used a No.51 drill).

Where the instructions finally leave you in suspense, is in the arrangement whereby the pull rods are attached to the brake actuator pivots and cranks.

No proper description and, as it turns out, a misleading and inaccurate photo of the arrangement on the specimen used in the illustrations.

The parts supplied as etchings are usable and reasonably accurate but the assembly needs proper explanation and some additional parts are needed.

The brake actuation cross shaft acts (on the prototype) to rotate cranks which are attached to the extremities of the shaft and the cranks are connected at the other end  to the end of the pull rods ... the attached photos show the arrangement.

The ends of the pull rods themselves ARE NOT directly connected by a cross shaft .... which is what the kit instructions appear to suggest.

To be entirely accurate, the actuation cross shaft need to be 5mm in diameter, far larger than the supplied steel items.
However, the frame support brackets, cranks and the hand brake column linkages need to be threaded onto this shaft, so the supplied nickel silver parts need drilling out to 5mm. While the support brackets and cranks have enough "meat" on them to withstand opening to 5mm, the hand brake linkage is "marginal".

First, I assembled the rigging as supplied, in order to mark on the frames a positive location for the cross-shaft support brackets.
The instructions suggest these nickel silver brackets be glued to the steel frames but I wanted something a bit more secure.
There is very little overlap between brackets and frame but enough to drill clearance for a 10BA nut and bolt which, in conjunction with a spot of Araldite, should be sufficiently strong.

If you are going to use the supplied steel shaft (in preference to replacing with a 5mm diameter shaft), before fixing the brackets to the frames, drill out to 3mm to accommodate the shaft (if replacing the shaft then drill to 5mm).

You will also need to drill out to 3mm the two components of the handbrake linkage if using the supplied shaft. If replacing with a 5mm shaft, I suggest turning a collar from brass rod to slide onto the 5mm shaft and then soldering the handbrake linkage to this...then drill out the the 5mm hole on the linkage to accommodate the shaft..

I opted to replace the shaft with a 5mm brass rod and the attached photos, taken prior to final fettling (in particular the handbrake linkage is hanging loose on the shaft) and fixing will, hopefully, make the foregoing a bit more comprehensible!

Now only the sandboxes need fitting to the frames and it will be ready for painting..... however, nothing with this kit (so far) has been as simple as it sounds!
My fellow Members, ask not what your Society can do for you, ask what you can do for your Society.

Offline AllWight

Re: GRS kit Midland Johnson 1F 0-6-0T
« Reply #20 on: Mar 23 2014 19:37 »
I must admit john that I use plastic tubing purchased from my local model shop for the spacers on the crops rods and as the collars for the top part of the brake hangers. Once painted you can not tell the difference between the brass tube or plastic.

Mark

Offline John Candy

Re: GRS kit Midland Johnson 1F 0-6-0T
« Reply #21 on: Mar 24 2014 07:19 »
Sandboxes.

These are supplied as four chunky whitemetal castings, which the instructions suggest be glued to the mainframes. The area of contact between the leading boxes and the frames (if mounted in the correct, rather low, position) will be minimal and I would not be happy relying upon glue.

However, before we get involved with fixing, the sandboxes themselves require quite a bit of attention.

For starters, one casting was about 2mm greater in (side-to-side) width than the other three (suggest you check yours) so first job was to file the oversize one down to match the others..

Next the "look" of the boxes is not correct. While, in general terms, the shape is more or less right, the slant of the lower front surface is too much towards the horizontal, with the result the the vertical front facet is noticeably too deep.

The angle of the slanted surface was filed so that the vertical facet is 5mm deep and the edges were then rounded off with emery.

The flat tops (i.e. excluding the fillers) of the sandboxes need to be 17mm below the upper edge of the mainframes, so the frames were marked in the appropriate position and the boxes offered up.
The outline of the boxes was marked on the frames and the boxes and frames were numbered.

Next  10BA clearance holes were drilled in the frames for attachment of the boxes. The numbered boxes were again offered up to the frames and the boxes were lightly attached with a small drop of cyano to hold them while the positions of the holes in the frames were marked by running the No.51 drill through the holes in the frames to leave a shallow diimple. The boxes which were then removed (and the glue residue cleaned from frames and boxes) then drilled to take 10BA screws.
After the screws had been screwed into the sandboxes, the heads were cut off and the sandboxes were then bolted and glued to the frames.

Now the chassis is ready for a coat of primer.

To sum up progress so far : There has not been any problem which, with a bit of lateral thinking and perseverence, cannot be overcome relatively simply.
The instructions are inadequate at best but the quality of the wheelsets and many of the other chassis components is far better than many other GRS kits I have constructed.

Next the wheel sets will be re-fitted in the frames and some testing on the rolling road 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

Re: GRS kit Midland Johnson 1F 0-6-0T
« Reply #22 on: Mar 04 2015 12:20 »
Well, it was only a matter of time before the 1F would be dragged from the shadows and back onto the workbench.

Project was shelved almost a year ago when the concrete mixer and garden took priority.

As it was left, the chassis was ready for painting BUT I then spotted something which I had missed until then.
The brake hangers and blocks supplied are of the old "sandwich" type, on which the block is pivoted between a pair of hangers.

All but one photo (and that a very early photo) show the single hanger type where the block fits over/around the hanger.

Off came the brake parts and the whole caboodle was "parked" in a corner until sufficient enthusiasm (by now worn wafer-thin by all the problems) could be revived.

Well, that happened yesterday and I now have a fresh set of brake hangers/blocks.
The hangers are made of aluminium and the blocks are whitemetal castings which were surgically removed from their hangers (they were left-overs from another GRS kit which required a "transplant" of parts).

Blocks were superglued to hangers and we are set to make progress!

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

Offline Geoff Nicholls

Re: GRS kit Midland Johnson 1F 0-6-0T
« Reply #23 on: Mar 04 2015 20:54 »
A nice piece of work so far, John. Of course Johnsons work for the Midland was merely a pastiche of the dynamic and innovative work he did for the great Eastern Railway(there was a bit of a ruckus when he moved the carriage door hinges from the right hand side, to the left!).
I was wondered if I could backdate the 1F to either:
class 417 wheelbase 7' 7" + 7' 8" wheels 5' 3" dia
or
class 477 wheelbase 7' 7" + 7' 11"  wheels 5' 1" dia.
I don't suppose the 1F matches either of them?
Geoff.

Offline John Candy

Re: GRS kit Midland Johnson 1F 0-6-0T
« Reply #24 on: Mar 04 2015 21:33 »
Geoff,

The 1F has 4ft 7in wheels and the wheelbase is 7' 4" + 7' 8".

Not impossible but you would need a pillar drill to get through the thick (3mm) steel frames with accuracy and there would be a lot of effort required to re-profile the frames without mechanical aids.

The body is brass, so there is not the problem of having to perform surgery on resin parts!

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

Offline Geoff Nicholls

Re: GRS kit Midland Johnson 1F 0-6-0T
« Reply #25 on: Mar 04 2015 21:52 »
hmm, better to scratch build and buy useful bits separately. I hadn't realised the wheels were smaller.
As an aside, the 7' 7" Johnson used, was continued by Adams and Worsdell used it for the highly successful  Y14/J15 

When you build the body, will you keep the boiler separate to facilitate spray painting, or just do it as one whole unit?
Geoff.

Offline John Candy

Re: GRS kit Midland Johnson 1F 0-6-0T
« Reply #26 on: Mar 04 2015 22:01 »
Geoff,

I haven't yet got as far as working out how the body is to fit together ...... let me get the chassis running first.

I am not encouraged by the first sentence of the instructions relating to the running plate.......it says some of the holes are etched in the wrong places!

Add to that the list of "design errors" which Andy listed earlier in this thread and it sounds as though it will be a case of "suck it and see"!

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

Offline John Candy

Re: GRS kit Midland Johnson 1F 0-6-0T
« Reply #27 on: Mar 05 2015 19:07 »
A free-running chassis at the first attempt... it stands "trim" on plate glass.....the compensation works beautifully....mechanically, it has be the best GRS chassis I have yet assembled.......why can't they all be this good?



It is really heavy, the steel frames are 3mm thick (about twice the "norm" for a GRS kit)  the wheels are cast iron with steel tyres and 10mm axles and run "true as a die" (far superior to the Slaters wheels usually supplied with GRS kits). The steel coupling rods are good and strong, sleeved with (larger than usual for GRS) brass captive bearings . I would go so far as to say that anyone wanting to use it as the basis for a live steamer would not be disappointed.

After the initial "niggles" requiring a few modifications, I am very happy with the result (and I don't often say that about a loco kit)!!





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

Offline John Candy

Re: GRS kit Midland Johnson 1F 0-6-0T
« Reply #28 on: Mar 08 2015 14:00 »
Before taking up the challenge of the superstructure, I spent a couple of days collecting photos of Johnson 1F locos.
The "instructions" with the kit (if you can call them that) are abysmal.
No diagrams/drawings/photos showing how the body parts fit together or covering the placing of the details.

The written instructions cover less than an A4 sheet of (widely-spaced) type .... would probably more useful on a roll in the bathroom than as kit instructions!

What quickly became apparent was that "Johnson 1F" is a generic term which covers several different classes of loco.
The kit states it is for the "1377" class (which under the 1907 re-numbering scheme became 1660 to 1844) and there are dimensional and detail difference between this class and the others.

Having detached from the fret and cleaned up the major components, first task was to correctly locate the running plate on the chassis.
The instructions warned that the holes for the mounting (to chassis) bolts were etched in the wrong places...so first task was to elongate the holes, as per instructions.
The instructions then tell me to solder the locating nuts to the running plate......well, since most of the metal to which the nuts would have been soldered had now been filed away, they are being a trifle optimistic!
I shall have to cut thick brass plates, drill and tap them and then solder to the running plate.

Offering up the parts of the bunker to the running plate, soon showed that the locating slot (in the running plate) for the cab coal front plate is not in the correct position.

Checking the underside of the running plate revealed that the two etched rebates for the valances are not spaced at equal distances from the edges (one side is 1mm further in than the other).

That's enough problems for now!

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

Offline AllWight

Re: GRS kit Midland Johnson 1F 0-6-0T
« Reply #29 on: Mar 09 2015 13:37 »
For a moment there John I thought you were being highly complimentary of GRS with reference to the chassis assembly of the loco then I read the next installment and its back to finding fault with castings or finished items as well as apportionning blame. You are an accomplished modeller I am certain you can cope with these challanges so try to put a positive spin on your issues that arise it may well come across better to joe public who can read this. I have built lots of the GRS loco kits and i agree there are good and bad ones. However speaking as a modeller I like these challanges.

Keep modelling

I look forward to seeing the loco up and running soon

Mark