A K's Johnson 2F

[Nick Lawson]

While the tender frames are in the "paintshop" I have reverted to the loco body. The offside firebox side was deformed, such that sitting it on the footplate assembly left the boiler lopsided. After much humming and ha-ing I tacked the cab front in position to hold the boiler level at the rear and soldered the boiler assembly in position, filling in the gap in the bottom of the firebox from the inside.  I forgot to take "before" pictures, but pic1 gives an idea.

 

Pic2 (sorry it refuses to display the right way up) shows the "after" together with a reverser linkage I have made out of scrap etch. It still needs to be attached to the frames. You can also see the various bits of filling required.

 

Of course, I got carried away while soldering everything in solidly and included the cab front, having lost sight of the need to take it back out to get the rear wheel boxes in place. But they are also wonky, so I may replace them anyway.

 

Edited December 31, 2022 by Nick Lawson
Didn't intend to post that soon

[Nick Lawson]

I've been having a bit of "fun" recently, trying to marry up the motor + loco frames with the superstructure.

 

My intention was to drive the middle axle with a motor facing forward inside the boiler barrel. I had previously assembled a High Level RoadRunner+, which has an articulated  final drive allowing some leeway in positioning. (pic1).

 

Mistake 1 was to solder this into a final position which I had determined before the motor, axle, frames, boiler and running plate were all in one piece. My final position was of course unsuitable to allow the motor to be slipped into the boiler while attached to the frames. Fun1 was thus to un-solder the articulation without melting the plastic gears. Achieved. Tick. I have learned that it is better to get it all together and temporarily fix the angle  of the articulated drive with a tiny drop of superglue which can be removed more easily and replaced with a more permanent fixing when everything is right.

 

I then discovered that even freeing this up I still couldn't get the motor+frames into position nicely. At the beginning of this saga I had followed the original kit instructions and soldered a fixing machine screw in position underneath the smokebox. (pic2) This is not a good idea if you need to slide the frames longitudinally to slip the motor into the bottom of the boiler. With hindsight I wish I had soldered a captive nut into the body instead, as I subsequently did at the cab end. I have been bracing myself to do something drastic to cure this, but thankfully this has not been necessary.

 

The next fun was the realisation that mounting the motor in the gearbox horizontally caused problems, so I rotated it 90 degrees and refixed in the vertical plane.

 

Then finally I found that the now unused mounting lugs on the gearbox were  fouling the scrappy join between boiler and firebox, so I resorted to snipping these off. Et Voila! It fits, it fits! (pic3)

 

 

[Barclay]

Looking good. I have just had the same 'fun' putting a modern chassis with the same gearbox into a K's Coal Tank, so I feel your pain. The Dremel and its burr were in regular use to carve out enough room inside that's for sure!

[Nick Lawson]

@BarclayA fellow sufferer! Good luck with the rest of your build.

 

There will now be a short intermission in this one, while my heating system is replaced. Oh look, it's about to get much colder again.

 

 

 

[Nick Lawson]

My “intermission” has been longer than expected – Real Life having triumphed over Optimism again (dammit!)

 

Now... where was I...?

 

Never having done this before, I had assembled the Gibson tender wheelsets without any spacers and was surprised to find how much slop the tender had [pic 1], even on my sharpest curve (~ 32 inches). I haven't made up the Gibson driver wheelsets yet so my Cunning Plan was to experiment with a set of (slightly too small) Romfords I had - and matching axles which I acquired. I can screw and unscrew these repeatedly to add/modify packing washers, saving the one-shot Gibsons from damage. I started with a pack of Gibson mixed shim washers (1mm, 0.5mm, 0.25mm). Apart from all this it was just heartening to see the loco on wheels, even if they are the wrong ones. [pic2]

 

In broad terms, the answer is that I need hardly any sideplay. (The more precise answer must wait until I stop fiddling about). The gear train will be on the centre drivers and these are packed with almost no sideplay - according to my old car engine feeler gauge it's currently 12 thou ( 0.3mm). The front and rear axles currently each have about half a mm play.

 

Somewhere along the way I came across https://www.rmweb.co.uk/topic/98857-building-a-4mm-scale-mpd-midland-3f-0-6-0/?do=findComment&comment=1884166 and, albeit this table is intended for P4, I thought it looked useful, although it assumes that the play will be on the centre wheels which is the opposite way round to my arrangement. I'll try to see how my empirical approach (in EM) aligns with it.

 

One drawback of using the Romfords for my experiment is that they have deeper flanges than the Gibsons and, with current packing, these chunter over the tops of the chairs on sharp curves. However, I think that there is enough play that the Gibsons will be ok.

 

Also of course, I haven't fixed the motor assembly to the Romford axle, so this is all just hand-powered, so far.

 

A further twist is that all the above assumes the standard 16.5mm back to back for em gauge. I have however seen a discussion elsewhere that recommends a b2b of 16.65mm for smoother running. I'll have to think about that some more.

 

Anyway, what sort of side play do y'all allow on your loco axles?

[micklner]

Use Peco Fibre washers on the Tender , cut a slot in them and push them onto the axle, that is if you do not want to remove the wheels again. Sounds tight for the loco wheels to me. The Gibsons are thinner so they should give some more room.

[Buhar]

Hi Nick

 

I somehow missed this at the end of last year despite occasionally checking @Compound2632's activities as a means of ensuring I've not overlooked any matters MR/LMS.  It's often more useful to hear of mistakes and methods to correct them or how to deal with a kit's failings than to follow a smooth build.  Attracting wise comments from the likes of @micklner and @Izzy only helps further.  Also I find your writing style really engaging.

 

Best wishes

Alan

[Nick Lawson]

@Buhar Thank you for your kind words.

 

@micklner Thanks Mick. I like the slit washer idea.

The drivers may indeed need more slack, I'll see how I get on. To give more context, I'm trying to eradicate slack as much as I can for two reasons:

1. Because this is an EM build there is minimal space available inside the bodywork and I want to avoid wheels rubbing on the body. In particular, opening up the slots in the cab for the rear drivers has already thinned the locating ridges for the cab side-sheets so I don't have much left I can remove.

 

You might regard this lack of space as a self-inflicted wound, but hey... 😀

 

2. The other factor is that I currently have one working loco, purchased from Ebay. This works fine except one route through my self-built double slip point, built on a curve. The loco in fact runs correctly tender first, but not loco first, derailing every time. Having tried tweaking everything to no avail, I wondered if it was the loco itself. This has quite sloppy compensation, so I am hoping my self-build loco will work with my self-build point. If not, I may have to rip out the slip and start again, which I'm keen to avoid.

[hayfield]

Nick

 

Firstly with the loco wheels, Romford/Markit wheel flanges are notoriously over scale and in the past  builders use undersize wheels, plus the thickness of the wheels could also cause an issue inside the splashers

 

I have just measured a Romford driver 2.6mm wide and the flanges are 2mm bigger than the tyre. A Gibson driver is 2.1mm thick and the flange is 1mm wider than the tyre, I have a DJH 1366 to convert to EM gauge, I will build the chassis using Romfords, once its been painted I will fit a set of Gibson wheels more to get clearance in between the cylinders

 

As for the curved slip, they are very hard to build on the curve as inertia wants to send them the wrong way, could it be the side play rather than the compensation that is the issue (just a thought) 

[Nick Lawson]

15 minutes ago, hayfield said:

Nick

 

Firstly with the loco wheels, Romford/Markit wheel flanges are notoriously over scale and in the past  builders use undersize wheels, plus the thickness of the wheels could also cause an issue inside the splashers

 

I have just measured a Romford driver 2.6mm wide and the flanges are 2mm bigger than the tyre. A Gibson driver is 2.1mm thick and the flange is 1mm wider than the tyre, I have a DJH 1366 to convert to EM gauge, I will build the chassis using Romfords, once its been painted I will fit a set of Gibson wheels more to get clearance in between the cylinders

 

As for the curved slip, they are very hard to build on the curve as inertia wants to send them the wrong way, could it be the side play rather than the compensation that is the issue (just a thought) 

John,

Yes I had compared the size of my temporary wheels with the intended permanents and in diameter over the depth of the flange the 21mm Gibson is only a smidge larger than the 20mm Romford.

 

I'm not really bothered about the out-of-scaleness of the Romfords, I only mentioned it as making it difficult to tell whether the loco rolls satisfactorily with the current complement of shims. And, as you observe, the fact that the Romfords are wider means that if I have chopped enough whitemetal out for them to fit  that means that the Gibsons will be ok.

 

When I said the compensation was sloppy I suppose I really meant that "the (compensated) wheelset is sloppy". I haven't tried fiddling with that loco (somebody else's modified LMS 4F) as a. it works otherwise and b. it is anachronistic for my time period so may well be moving on when I have a stud of super-duper locos (but that may be sometime after hell has frozen over at my rate of progress).

 

One of the other aspects I've learned from all this is that there is no such thing as a standard EM gauge frame spacer. I have used Gibsons, which are wider than Comets, but narrower than the 14mm spacers purveyed on ebay (I think by a gent of this parish). Having seen how much slack I have with the Gibson spacers, I'd go for the wider option next time as it would give a better overall look and more useful space between the frames.

 

What frames/spacers are you planning to use for your 1366?

 

 

[Nick Lawson]

@hayfield Ooh, I've just spotted the link to your turnout workbench! Some catching up to do.

[Compound2632]

2 hours ago, Nick Lawson said:

Some catching up to do.

 

I was thinking of slipping in some remark about him doing traps as well but I thought to myself: Why? What's the point?

[cctransuk]

On 11/01/2023 at 21:07, Nick Lawson said:

I've been having a bit of "fun" recently, trying to marry up the motor + loco frames with the superstructure.

 

My intention was to drive the middle axle with a motor facing forward inside the boiler barrel. I had previously assembled a High Level RoadRunner+, which has an articulated  final drive allowing some leeway in positioning. (pic1).

 

Mistake 1 was to solder this into a final position which I had determined before the motor, axle, frames, boiler and running plate were all in one piece. My final position was of course unsuitable to allow the motor to be slipped into the boiler while attached to the frames. Fun1 was thus to un-solder the articulation without melting the plastic gears. Achieved. Tick. I have learned that it is better to get it all together and temporarily fix the angle  of the articulated drive with a tiny drop of superglue which can be removed more easily and replaced with a more permanent fixing when everything is right.

 

I then discovered that even freeing this up I still couldn't get the motor+frames into position nicely. At the beginning of this saga I had followed the original kit instructions and soldered a fixing machine screw in position underneath the smokebox. (pic2) This is not a good idea if you need to slide the frames longitudinally to slip the motor into the bottom of the boiler. With hindsight I wish I had soldered a captive nut into the body instead, as I subsequently did at the cab end. I have been bracing myself to do something drastic to cure this, but thankfully this has not been necessary.

 

The next fun was the realisation that mounting the motor in the gearbox horizontally caused problems, so I rotated it 90 degrees and refixed in the vertical plane.

 

Then finally I found that the now unused mounting lugs on the gearbox were  fouling the scrappy join between boiler and firebox, so I resorted to snipping these off. Et Voila! It fits, it fits! (pic3)

 

 

 

My usual solution to this situation is to mount the Highlevel Roadrunner+ drive extender on the rear axle, facing 45 degrees downward / rearward. That usually places the motor in the firebox / rear of the boiler, and on the boiler centreline - for ease of inserting into the boiler if necessary.

 

I'm in the process of rechassising several Airfix Standard 4MT 2-6-0s using this configuration in Kemilway chassis kits.

 

Running is very smooth - though I think that I should have selected a lower reduction ratio for the Mitsumi motors that I use - the top speed is lower than I would wish.

 

John Isherwood.

[Nick Lawson]

10 hours ago, Compound2632 said:

I was thinking of slipping in some remark about him doing traps as well but I thought to myself: Why? What's the point?

I see now I should have worded my previous post differently! Unintentional pun.

[Nick Lawson]

10 hours ago, cctransuk said:

My usual solution to this situation is to mount the Highlevel Roadrunner+ drive extender on the rear axle, facing 45 degrees downward / rearward. That usually places the motor in the firebox / rear of the boiler, and on the boiler centreline - for ease of inserting into the boiler if necessary.

John, I can't remember exactly now. I was originally thinking in terms of driving the rear axle, but I think I had a spacer in the way. Also very small firebox.

 

I'll bear this in mind for another time though. Thanks.

[hayfield]

13 hours ago, Nick Lawson said:

John,

Yes I had compared the size of my temporary wheels with the intended permanents and in diameter over the depth of the flange the 21mm Gibson is only a smidge larger than the 20mm Romford.

 

I'm not really bothered about the out-of-scaleness of the Romfords, I only mentioned it as making it difficult to tell whether the loco rolls satisfactorily with the current complement of shims. And, as you observe, the fact that the Romfords are wider means that if I have chopped enough whitemetal out for them to fit  that means that the Gibsons will be ok.

 

When I said the compensation was sloppy I suppose I really meant that "the (compensated) wheelset is sloppy". I haven't tried fiddling with that loco (somebody else's modified LMS 4F) as a. it works otherwise and b. it is anachronistic for my time period so may well be moving on when I have a stud of super-duper locos (but that may be sometime after hell has frozen over at my rate of progress).

 

One of the other aspects I've learned from all this is that there is no such thing as a standard EM gauge frame spacer. I have used Gibsons, which are wider than Comets, but narrower than the 14mm spacers purveyed on ebay (I think by a gent of this parish). Having seen how much slack I have with the Gibson spacers, I'd go for the wider option next time as it would give a better overall look and more useful space between the frames.

 

What frames/spacers are you planning to use for your 1366?

 

 

 

Nick

 

A well respected EM gauge modeller asked me to build a few turnouts for him, and stipulated a few things he required for faultless running

 

One thing he stated was that everything revolved around his wheel back to back gauge, if a wheel does pass the B to B test it is not used (I have several B to B gauges all vary slightly)

 

Probably backed up from a piece of advice from Martin Wynn (Templot) to fit check rails with a check rail gauge

 

Lastly a friend who had a P4 layout (one of the early trail blazing layouts)marked all his stock so that each loco, wagon and coach always faced in the direction it ran best, simply for the best running.  

 

I have noticed they vary, especially as some makes use the same spacers for EM & P4. I always try to have the driven axle with limited side play, If its an end one in an 0-6-0 loco then its only the centre axle which can move sideways, or if the centre axle is fixed then both outer axles have side play. Your de-railing loco I would firstly check the B to B then perhaps adjust side play. And or study where it de-rails on the slip, a slight adjustment might be needed

Edited April 28, 2023 by hayfield

[Nick Lawson]

As a displacement activity away from wheel settings I started making up coupling rods. Initially I had bought a set of Gibson rods but then saw various threads about "proper" rods for 6-coupled (and above) locos having separate knuckle joints and not articulating on a driver crank.

 

I considered trying to modify my rods in this style, but luckily spotted that Brassmasters sell replacement Midland 3F and 4F coupling rod etches for a princely £6.  As these have the same wheelbase as the 2F, I bought a set of 3F rods as hopefully being indistinguishable in 4mm scale. These solder together much like any others, but the etch provides extra parts to build up the bosses on the bearings and knuckle joint. In usual fashion they offer a choice of plain or fluted side out, which made me realise I'd never consciously noticed which were appropriate. A delve through some literature suggests plain.

 

As usual, after weeks away I was initially completely unable to wield a soldering iron to any effect. Much swearing later I now have these half built items. The joints aren't pinned yet and the whole lot still needs some filing, but I'm getting there. A quick eyeball check suggests that Brassmasters and Gibson agree on the dimensions of these rods, so I am optimistic that these replacement rods will fit my frames that were set up using the Gibson rods.

 

I suppose I'd better finally get around to fitting the wheels.

[Nick Lawson]

On 27/04/2023 at 09:54, micklner said:

Use Peco Fibre washers on the Tender , cut a slot in them and push them onto the axle, that is if you do not want to remove the wheels again.

@micklner Thanks Mick, now fitted as per your advice. The fibre washers were Comet rather than Peco because I had them. I had wondered about putting 1/8" dia washers on 2mm axles, but it seems fine.

 

Tender no longer trying to do a Vin Diesel drift round the bends.

 

 

[Nick Lawson]

 

Johnson 2-2-2 anyone?

[Nick Lawson]

Back to the tender:

 

A while back I started to fiddle about with brake gear, combining plastic Gibson hangers, (flimsy but great insulators), with the Mainly Trains brake gear etch from Wizard. Having stopped the wheelsets slopping from side to side I have now completed this stage. The holes in the brake hangers are quite large, so I followed the common practice of inserting short lengths of brass tubing into them to slip over the wire mounting points. In fact, having lost the first length of tubing into thin air, I superglued the end of a long length into the hanger and sawed the required length off the tube afterwards.

     I started by soldering the metal components - a high risk strategy given a wavering hand and plastic components all too close - but eventually decided superglue was my friend ( this week at least!). The etch contains a variety of lengths of rodding, cranks, adjusters and what have you; so, "for the craic", I faked up the front end of the mechanism (pic 2). The prototypical mechanism was of course more complicated than this.

    The main cross rod was inserted by drilling a hole through one side of the whitemetal body and part way through the opposite side. The cranks were doubled up from the etch. The angle of the pulling cranks is wrong, but was determined by using the shortest length of rod unmodified. A better effect could have been achieved by shortening these rods and soldering on adjuster ends, allowing the cranks to be set round 90 degrees or so.

    The displayed result is actually my second attempt at assembling this mechanism. The first attempt was almost right until I started to "improve" it by small adjustments with a soldering iron. After cutting out the resulting mess and salvaging the cranks, the mk 2 model was assembled with superglue and much less bad language.

   The main consideration though was that while most of the rodding is attached by the hangers to the brass frames, the front end is attached  to the whitemetal body via the cross rod. In order to separate body and frames the longitudinal rod ends can be unhooked from the cranks. They are only pushed on to the rather crude looking pins which I need to file down a bit.

    Pic 3 shows that you can just about see bits of brake gear here and there, so I feel it was worth the effort. I have added a representation of the external bearing plate for the cross rod on this side of the body. I need to do the same on the other side to cover the hole through which I inserted the rod. 

 

 

[Nick Lawson]

I moved on to hang the brakes on the loco but when I offered up a hanger I could see it wouldn't clear the bottom of the firebox. I wondered if the Gibson plastic hangers were undersize but they matched some alternative Mainly Trains etched brass ones I have, so I concluded the holes were in the wrong position. 

 

I had known that the pre-drilled holes on the tender frames were in the wrong place as they were on the wrong side of the wheels, but these ones had looked about right. Another time I will try to remember to check these details while frames are still flat packed, as much easier to drill. I inspected some pictures and estimated positions for the new holes.

 

Coincidentally, I see this morning that another parishioner has been similarly occupied on a different kit:

 

[Chas Levin]

Hello Nick, very nice work so far; I just today found and read through your thread and I look forward to further instalments...

[John-Miles]

On 11/05/2023 at 19:47, Nick Lawson said:

As a displacement activity away from wheel settings I started making up coupling rods. Initially I had bought a set of Gibson rods but then saw various threads about "proper" rods for 6-coupled (and above) locos having separate knuckle joints and not articulating on a driver crank.

 

I considered trying to modify my rods in this style, but luckily spotted that Brassmasters sell replacement Midland 3F and 4F coupling rod etches for a princely £6.  As these have the same wheelbase as the 2F, I bought a set of 3F rods as hopefully being indistinguishable in 4mm scale. These solder together much like any others, but the etch provides extra parts to build up the bosses on the bearings and knuckle joint. In usual fashion they offer a choice of plain or fluted side out, which made me realise I'd never consciously noticed which were appropriate. A delve through some literature suggests plain.

 

As usual, after weeks away I was initially completely unable to wield a soldering iron to any effect. Much swearing later I now have these half built items. The joints aren't pinned yet and the whole lot still needs some filing, but I'm getting there. A quick eyeball check suggests that Brassmasters and Gibson agree on the dimensions of these rods, so I am optimistic that these replacement rods will fit my frames that were set up using the Gibson rods.

 

I suppose I'd better finally get around to fitting the wheels.

I have used the Brassmasters coupling rods on my 2Fs (they are Gibson not Ks) and I am very pleased with the results. I think that avoiding the join on the  centre coupling rod pin reduces the amount of slop (that's a technical term !!) and gives better running.

 

I also have an ancient Ks 2F in LMS livery with Romfords and a Triang motor. Not seen this thread before but I have enjoyed looking through it.

[hayfield]

On 02/06/2023 at 07:47, Nick Lawson said:

I moved on to hang the brakes on the loco but when I offered up a hanger I could see it wouldn't clear the bottom of the firebox. I wondered if the Gibson plastic hangers were undersize but they matched some alternative Mainly Trains etched brass ones I have, so I concluded the holes were in the wrong position. 

 

I had known that the pre-drilled holes on the tender frames were in the wrong place as they were on the wrong side of the wheels, but these ones had looked about right. Another time I will try to remember to check these details while frames are still flat packed, as much easier to drill. I inspected some pictures and estimated positions for the new holes.

 

Coincidentally, I see this morning that another parishioner has been similarly occupied on a different kit:

 

 

 

Looking very good

[Nick Lawson]

@Chas Levin @John-Miles@hayfieldThanks for your recent kind comments

 

Sadly the next installment is a step backwards. I've been otherwise engaged for several weeks on some worthy-but-dull diy. Coming back to the bench yesterday I was dismayed to find a bad case of flux-induced rust affecting the tyres, axles and CSB springs of the tender. Wah! I dismantled this lot again and cleaned off the rust. I was going to oil it all to prevent recurrence, but it occurred to me that the sides of the tyres wouldn't have been shiny anyway. I have a small bottle of Mig Brown Oxide primer, which says vaguely that it is "multi-surface" so I tried brushing this onto the tyre sides. This matt finish accentuated the shiny black plastic wheel centres and the even shinier axle ends.  I cleaned off the latter and primed them and will slap matt black over these and the wheel centres later.

 

Pictures later when I've completed this manoeuvre.