I share your trepidation with getting stuck into modern chassis construction. I have a box with all the chassis parts for a small Metro sat in a draw with the necessary specialist tools waiting for sufficient confidence to build it. I will do it, although keep putting it off by doing other things.

You've made a good start and have a plan, so I'm watching and learning with you and sending good karma to the valleys.

Bon courage mon ami 👍

I think the trick, if there is one, is to do things methodically one step at a time, even if that means one task at a time, then to step back from the job for some thinking time before starting the next task.  It’s not a race, and if it takes me a year to complete I’ll be happy.  Next task  will be the frame cross-members; the kit offers 00, EM, and S4 but this task isn’t finished yet; as I’m working in 00 I’ll need to trim and file the protruding parts of the rear axle bearings down flush with the inside face of the frames first, to provide clearance for the gearbox, which is I suspect going to be time-consuming and frustrating.  They protrude about 1.5mm, and I may be able to get the bulk of the metal off with a slitting disc; the instructions say to file them down, which feels like it’s going to be onerous. 
 

But now I’ve started, I intend to take my time but keep momentum.  Thank you for the good karma, longchap, and if my efforts help you to take Confucius’ single step with your Metro, I’ll be delighted, so I’m sending as much good karma your way in return!

ATB, mon captain.  

Mr Johnster, sir, before you file down the insides of the brass bearings, my advice would be to:

i) turn the frames so that the outside is resting on the bench, put some flux right round between the brass bearing and the N/S frames and apply the iron, letting the solder flow right round the circumference of each bearing

ii) when that is done, cut most of the protruding bearing off with a file-toothed piercing saw and then clean with with a file

iii) gently reaming out any brass flash from the inner face of the bearings

iv) after the above, take a drill bill larger than 1/8 of an inch, in your fingers only, and twirl around both sides of the cleaned up bearings. You only need to do this a little, but it should create a small channel on both sides of the bearing, to aid putting the axles in and then lubrication.

Good luck!

Thank you for this good advice, my West British friend, especially the file-toothed piercing saw.  The internal surface of the bearings is pretty good as is, and won't need any work unless the axles are a tight fit; haven't try-fitted them yet and am working on the assumption that all shall be well and all manner of things shall be well, which might be risky, so a tryfit will be done next session.  The reaming was of the bearing holes in the frames, which are deliberately made undersize by HL and you are instructed to open them out until the bearings fit, presumably to ensure a good fit.  As I said, I did this 'little bit at a time' until they just fitted and soldered them.  I'm a little concerned that my solder joints will fail under the stress of sawing and filing, but they feel pretty solid; I am thinking that it would do no harm to reinforce them with a dab of runny superglue to capilliarise into the joint all the same.

I like the idea of the lubrication channel, though, and a brief hand twirl with a 1/8th drill followed by a cleaning up will do no harm either, but I'll tryfit the axles first to get a feel for how they run in the bearings.  This will ultimately be a compromise, as they must run freely but not loosely.  But a perfect fit will be prone to stiffness as a result of temperature changes, won't it?, as we are deaing with a steel axle running in a brass bearing fixed in a nickel-silver frame, and all of those metals presumably expand and contract at differing rates when the temperature changes, so there will have to be some play, but it must be minimal

I am particularly aware of what expansion and contraction can do on a layout after my teenage attic layout, in an attic insulated (not) for the purpose by Buffalo Bill Attic Conversions PLC, aka my old man, bodgerigar extraordinaire; the layout tore itself to pieces.  In reality I'm prolly worrying too much, as the layout is within the living area of the flat and reasonably cool in summer/warm in winter, and I've never experienced any such issue with it, but the mental scars of the teenage disaster are still there...

Probable session on this later this evening, as the other frame needs it's bearings fitting and then I'll do the tryfitting and fettling before attacking the protrusions.  That'll prolly be enough for tonight, but I'd like to have it sorted so as to clear my head for the frame spacers, which sound more like a weekend job!  I think these should be fairly straightforward, with much less fettling and filing, but that looks like famous last words even as I type it...  The issue here will be to ensure that the spacers are at proper right angles to the frames, and the axle bearings align with each other.  On buildings and wagon kits I use Legos (plastic bucket full of your choice from Lego shop in town, £6, excellent value and useful for all sorts of formwork, recommended) to ensure this, but I doubt there'll be room for this dodge in this case

Onwards and upwards, or at least diagonally and sideways!

Two frames, bearings fitted, and the protrusions hacksawed off with a junior hacksaw with the pieces secured in the vice.  I’ve cleared the swarf and debris from the bearings and tryfitted a 1/8th dia. rod, actually a screwdriver shaft of that size; all seems well.  The hacksaw made fairly clean cuts through the brass bearings, and the cleaning up of these surfaces with a file will be much less work than I’d feared. You can see where the side of the saw blade has polished the nickel-silver of the frame pieces, which acted as a guide for the saw, and a cleaning up session will still be needed; if there is any lumpiness to affect the fit of the gearbox, smooth running, which is the root object of the exercise, will be compromised!
 

So I’m quite pleased with myself; matters are proceeding much as I thought they should, and while I’m not running to time because there isn’t a timetable, I’m where I thought I should be at the present time.  

Cleaning up the inner protrusions of the bearings was only a few minutes work, filing the burrs away mostly.  It occurred to me that there was no need to cut the protruding bearings for the front axle, only the rear ones for gearbox clearance, but the securest way to hold the workpieces in the vices made it easier to hacksaw the front and rear bearings together anyway.  
 

So the next task was to fit the frame spacers.  These are tabs on the spacers and slots in the frames.  Starting at the front, which has to be folded along a fold line, and because it could stand up on it’s own while I soldered it in position; the instructions say to fit to the left frame, but I can’t see what difference it makes.  The next is the middle spacer, actually well towards the front just for’ard of the front axle; this was where the fun began.  Try as I might I couldn’t get the spacer to stay still while I soldered it.  The solution, it eventually dawned on me, was to weigh it down with something on top; what was to hand was the b2b. 
 

This did the trick; on to the rear spacer, mounted horizontally under wher the cab will go.  This was even fiddlier, and the big guns were called for…

On a roll, now, offer up the rh frame piece.  Of course, nothing lined up, and a bit of gentle benderising persuasiveness ensued, but we got ther eventually. 
 

Look, a chassis frame!  I’m a proper modeller after all, bask in my glory RTR peasants; oh, hang on a minute, it’s all a bit out of square and a little twisted.  Out with that 1/8th shaft screwdriver again to see if we can use it as a guide; it should turn reasonably freely when the alignment is correct and can be used as a fine-tuning guide to square things off.  And give you a bit of leverage for the benderising!
 

It worked!  Ok, don’t get carried away, that’s enough for tonight, well done Johnster you’ve earned the bottle of Newcastle Brown in the fridge.  Not going to do any more to it tomoz, having a chillax operating sesh instead.  But this isn’t as easy as the instructions suggest when you’re used to simple plastic construction kits.  Each instruction so far as thrown up situations in which you must work out for yourself how to carry out; ‘solder spacers to lh frame then solder rh frame to assembly’, for example, does not give much guidance when it comes to

holding things that repeatedly fall over, or how to ensure square and aligned bearings for food running without binding. 
 

This is of course all part of the fun and working things out for yourself adds to the satisfaction, and the feeling of achievement if you manage to get a good smooth slow runner at the end of it.  But so far it’s not been difficult (wait ‘til I get to the miniscule details of the brake rigging!).  Faffy, pushing the limits of Johnster’s ingenuity and problem-solving capacity, yes, but not (yet anyway; it’s still early doors) difficult. 

Having had a rest from the High Level coalface, I had another look at it tonight.  Only did one thing, next on the list, part 18 the cylinder support bracket.  Not rocket science even by my standards, a fairly straightforward foldup box shape with wing tabs to solder into slots in the front of the side frames.  You have to ensure that the top of the piece is level, but it sat level naturally in the slots, and so long as something is restraining the frame at the rear and the support bracket at the front so it stays where it is while you are poking it about with the soldering iron, there shouldn’t be much problem and there wasn’t.

It looks like this when you’ve done it, note that the bottom edge slopes downwards to the rear to match the angle of the cylinders.  
 

The next part is to make up the cuopling rod and drill out the crankpin holes in them, but I need to do a bit of instruction reading before I start that sort of shennigans, so no more for tonight!

i actually wrote that last night but didn’t post it for some reason.  I think I probably meant coupling rods not cuopling rods, though…

I’ve had a squiz at the instructions, and while the next job in them is indeed to make up the coupling and connecting rods, it is much later in the proceedings that wheels and axles come into play.  There is finishing off work on the chassis to do, the motion inspection covers and the internal motion, the valve gear representation between the frames, and it makes more sense to do these jobs and the gearbox/motor assembly first.  I am not comfortable with taking the rods off the fret until they are needed, as I am afraid of losing them. 
 

If I can save time and effort by using the Dapol wheelsets and motion, I will; there is nothing wrong with it and I’m not building the kit in EM or P4.  I might even be able to employ the Dapol keeper plate, which will sort the pickups and what looks like an admittedly finely detailed but probably highly fiddly brake gear assembly with plenty of discrete and tiny parts of the sort specifially designed to drive The Johnster nuts, or at any rate more nuts than he already is…

So I’ve decided that the best way to proceed for me is to finish the chassis and tick that off job done without taking the rods off the fret, not yet anyway.  After that I’ll start dismantling the Dap chassis and seeing what, if any, of it can be used.  

I’ve found my first mistake!  Hopefully rectifiable; the next move is to insert piece of wire through the small holes in the frame ahead of the cylinder support box and between the axles at the same level, leaving enough sticking out each side to trim to hold the tops of the brake assemblies.  But sum dam fule🥴, guess who, has covered the rh front hole with solder when he was doing the cylinder support box.  
 

I’ll try to redrill the hole later!

Phew! No real harm done and easily fixed and all part of the learning curve for the next one. Well done that man, you made a good mistake!

I've just managed to grab a place at a weekend loco building course in March, so can hopefully construct a small 2-4-0 tank chassis up to running stage, then can get started on the loco kits stash.

Best possible good fortune Mr J with your continuing build, which is reassuringly informative and entertaining.

Morning Jonners, 

Reading through this I have to say, hat's off for giving this a go. 

One observation if I may.......

I'm believe using the RTR keeper plate is a non starter. The pick ups on the Dapol/Hornby job are on the top of the chassis and contact the upper face of the rear of the tyres. 

Perhaps something could be cobbled up to dangle said pick ups from the top of the chassis, alá RTR ? 

Rob.