KATIE FROM SCRATCH – PART 3.

 

 THE MEAT AND POTATOES

 

This section is main part of the story, and I am writing with a degree of hindsight from the position of having actually run the chassis/boiler combination on the track, pulling half a dozen wagons (smug grin).  I must apologise up front for missing out on a picture of the chassis with wheels, cylinders, motion, blast pipes and superheater fitted, before fitting the boiler.   Actually, these went together more easily than I had expected they would, with the exception of the Return cranks, of which more later.  Sometimes the urge to Do Something overtakes the more rational self that looks after the documentation!

 

Please note that I am not an engineer either by training or especial aptitude, and I’m writing from the standpoint of someone whose experience is confined to changing the spark plugs on the car, servicing the motor mower and drilling holes in the wall to put up picture hooks and curtain rails.   I was always rather duff at plastic kits.

 

I’m dividing the text into processes, so that the issues I came across get a thorough airing.  I don’t think it’s especially useful to tell you chronologically that the Return Crank fits on after the Penguin (pivot for part of the reverser linkage)  - you have manuals and the list of assembly procedures from Part 2 of this saga as well.

 

I had many delays, due to low temperatures outside in late March and early April, coupled with waiting for the paint from Precision Paints and a rather fraught period in my non-railway life.

 

Tools

 

My update re tools in Part 2 has been overtaken by events, and what I used and bought are listed below.  The manual says you don’t need special tools to build Katie, but it all depends what you mean by “special tools”.   With hindsight I would say that everything listed below is more or less essential (but I expect others to disagree).

 

I already had the following in my toolbox:

 

  • Miniature screwdriver set.

 

  • Long-nosed pliers, with a good grip on the end.

 

  • Hammer (used gently!), heavy head better than one for fretwork, soft head for preference but probably not essential.

 

  • Plumber’s pliers – the ones with an adjustable jaw width – for all sorts of things you never expected to need them for.

 

  • Standard size G-clamps.

 

  • Good quality vice, for bending brass sheet.  Mine was inherited from my grandmother, and must be getting on for 100 years old (she was an amateur engineer, who wired up the first electric light in her house and was also a whizz at furniture making too).

 

  • A couple of standard screwdrivers.

 

I bought the following:

 

  • Set of BA spanners.  Roundhouse provides thin pressed steel versions of these in the kit, which, while they work, aren’t very comfortable to use.  I bought a set of decent ones for a tenner from Mackays (my local tool specialists, usual disclaimer) of Cambridge, and feel they were worth the money.  On occasion, having two spanners the same size comes in handy.

 

  • A set of needle files for the odd little delicate fettling, e.g. smoothing off the edges of the drop links (the curvy things in which the drop links move up and down to effect reversing of the valve gear).  Mine cost me a couple of quid at my local DIY, and I could probably have just about got by without them.

 

  • Miniature size G-clamps.  With hindsight, C-shaped miniature clamps would have allowed more clearance in awkward situations.  You need them to hold parts together while you do the soldering. They cost £2-something-or-other each, and I bought 2.

 

  • A Dremel drill.  Mine cost me £50 in Homebase and came with lots of attachments that were handy to get the connecting rods to fit, filing down the ends of protruding bolts etc.  Dremel isn’t necessarily the bestest – them as knows say Proxxon is the one to get – but the generic item’s size, speed and variety of attachments make it almost indispensable to the modeller.  Cost: £50.

 

  • Dremel drill bits, including a 1.6mm drill specified for drilling the cranks (of which more later). Cost: £8  (you can get individual drill bits elsewhere but you don’t get the plastic case).

 

  • Dremel drill chuck.  The standard-fit collet (thing to hold the drill bits and other business ends in place) won’t cope with the above-mentioned drills.  The proper Dremel chuck costs a tenner.

 

  • Dremel drill stand.  I suppose a cheap standard-size stand and drill would work, but the relative delicacy of the Dremel set up gave me confidence in what was for me uncharted territory.  It works rather well too!  Cost: £39.

 

  • Butane flame gun.  This is specified by Roundhouse as necessary to do the soldering, as a standard soldering iron can’t produce enough power to counteract the heat-dispersing properties of brass.  Cost: £27, but included a large 70:30 butane/propane canister that I am now using for Katie!

 

  • Jar of Baker’s No3 soldering fluid (flux) – again specified by Roundhouse.  Cost: £3 ish.

 

  • Roll of unfluxed wire solder - £3-ish

 

The total cost of these tools came to £160 (ouch).

 

Nuts, Bolts and Parts Management

 

Fitting screw-together parts is not especially memorable, and doesn’t really need much explanation, except to say that it is always wise never to open a section of packaging until you have identified an immediate need for the part(s) in question.  This prevents you from mixing things up.  However (there is always a However…) some of the bubbles contain spares/duplicates of screws, nuts, bolts etc that have no immediate application, and it isn’t immediately apparent that that’s what they are.  They are there in case you drop one under the workbench and can’t locate it amongst all the crud down there.  Keep anything you have opened in a sealed box until you need it, and try to link the correct bolt with the correct part.  I speak as one who didn’t consistently do this, and I mentioned to Barry of Roundhouse that labelling screws etc and including photos in the manuals would be a help to dunderheads like me.

 

Soldering

 

Soldering is needed to construct the body, as there’s no other way (a) to fix the front panel of the saddle tank onto the main part, and (b) to fix the saddle tank to the cab.  The instructions do say that you can drill and bolt the cab, but it’s rather expected that you’ll solder it.

 

I had never done any serious soldering before, so was rather nervous!  I discovered that, even if you’ve washed your hands, Baker’s Fluid can last on your fingers overnight without you noticing – I rubbed my eye the following morning and had to resort rapidly to the Optrex.  Treat it with much respect.

 

Re flame guns, I got a full-sized one.  Note that the lit flame is nearly invisible and very hot, so use with great care, especially avoiding inadvertently heating nearby combustible materials.  I kept both doors of my garage open and had the fire extinguisher handy, also the mower and its petrol outside in the garden – I’m a devout coward.

 

If you aren’t a Born Again solderer, take a tip and get a miniature flame gun that you can use in the kitchen to make crème brulee and impart artistic browning effects to meringues…

 

The way I did the soldering was to fit and clamp the parts as instructed in the manual.  Then I applied Baker’s fluid with a paintbrush, followed by a short length of unheated solder balanced precariously on the joint.  Then I applied the flame gun, using the plumber’s pliers to hold the very hot metalwork.  If I was lucky the solder went where it was wanted.  If not, I had to heat the errant solder lump with the torch and remove it with a screwdriver, which now has a nicely soldered tip.

 

If you are experienced with solder it shouldn’t be too difficult to do a better job than I did, but nevertheless I got there and the outside panels (where it matters) look OK after painting.

 

 

Painting

 

Painting is not just a case of “slap it on with the nearest brush.”  As mentioned in Part 1, I bought my paint and primer from Precision Paints of Colchester (found via Google and recommended by Roundhouse if you ask).

 

Precision Paints sell a book telling you how to get the best finish, and I’m afraid I followed very few of the precepts.  My garage is not warm enough in winter (and delayed my starting any painting at all, until I hit on the dodge of using a fan heater pointing at my cardboard box spray booth).  I don’t have an airbrush or a compressor, my garage is anything but dustproof and I don’t wear lint-free overalls and a facemask.  Therefore the finish on my engine is not perfect, but then it isn’t on full-size ones either!

 

You can use a brush, or an airbrush, or aerosols.  I opted for aerosols, and used 2 aerosols each of the following:

 

  • Grey etch primer – essential to get paint to stick to brass
  • White primer (Precision Paints say this is essential as the final perceived colour is affected by the primer, and their topcoats are designed to work with white primer – even black!
  • Dull black
  • LNER Doncaster green

 

Don’t think you’ll get away with one aerosol, as most of the paint will probably miss its intended target.  I now have two cardboard boxes (used as spray booths) beautifully enamelled inside!

 

Do take the trouble to shake the aerosol vigorously for at least 3 minutes before each paint session (to ensure proper mixing of pigments and propellant), and store it upside down, with the cap downwards.  The labels are deliberately put on apparently upside down to encourage this.

 

Clean the bare metal with the best solvent you can get hold of – paint thinners or, in my case, car brake cleaner from the car accessory shop, where I also bought high temperature heatproof black paint for the smokebox.

 

Do use fine wet-and-dry sandpaper to rub down the surface to be painted, whether painted yet or not – and wet the sandpaper too, to act as a lubricant.  Wipe dry with a lint-free cloth.

 

It’s best to take time putting on lots of thin coats, so that the paint doesn’t run, but natural impatience can override such good advice....

 

The first thing I painted was the smokebox, and I also painted the boiler (see picture of boiler suspended on garden wire) using the high temperature matt black paint.  In retrospect it was a complete waste of time to do the boiler, as it’s completely covered in a brass wrapper, except for the backhead inside the cab.

 

 

The next thing I painted was the chassis, using Blu-Tak to mask the wheel bearings.  This worked but the solvent in the paint made it very sticky to remove.  Perhaps best to use conventional masking tape! 

 

 

The brass boiler wrapper was painted green so that I could go ahead with assembling the boiler and chassis.  In the event, achieving steam up took me nearly a month longer than I had expected, as I used up paint quicker than I expected and had to order more.

 

I still need to put an extra coat of green on the cab/saddle tank and then paint the inside of the cab cream.  Then I’ll screw on the handrails and fit the dome.

 

 

Construction Issues

 

The worst thing to happen was that I botched the drilling and pinning of the nearside return crank.  The purpose of this is to fix permanently the position of said crank – which is the outside-most part fixed to the rear wheel and which drives the valve gear.  I made the mistake(s) of trying to get by without a proper chuck to hold the drill steady and padded the drill bit out to fit the collet that came with the drill as standard.  Nada!  To do this job properly you need a 1.6 mm drill and a means of holding the loco crank and the drill in alignment.  Hence the need for the drill stand.  Also, do set the drill to work at slow speed (for a Dremel) – 3,000rpm is quite fast enough, and if you turn up the wick all you do is polish the end of the drill so it don’t work no more.  The replacement parts from Roundhouse came promptly.

 

I made a second mistake in not giving the replacement main rear wheel crank a proper squeeze onto the axle quartering before screwing in the retaining screw – and it came undone and stopped the engine in mid test.  Easily fixed though.

 

I should also have taken a photograph of the completed chassis without the boiler.  Sorry about this.  The instructions suggest that you test it with a compressor – which rather stumped me, until I hit on the idea of connecting my electric car pump to the inlet of the superheater tube.  It worked – just like fixing it to a tyre valve.  The pundits say you should put 3 in 1 oil into the cylinder and valve in lieu of steam oil.  This I did – and, hey presto, it all worked!  No doubt a foot pump would work too – up to a point.

 

Next Episode

 

The next episode will be the finishing off of the painting, plus screwing/gluing/clipping on of various bits of “jewellery” round the engine.

 

I’ll document the fine-tuning process, and then the fitting of radio control. 

 

In the meantime I’ve included a movie clip of Katie under steam test on blocks.  This was the bit that made it all worth while

 

 

Richard Stamp 2006.

 

As always you can ask questions or offer help via the Forum section that runs along side there articles.

 

KATIE FORUM LINK