Another A1 Models diesel - part 5 bonnet.

Here's the bonnet etch;

I decided that the single large side grills were a bit too long, so I used strips of etch offcut to divide them into two smaller grills;

I did notice that one of the dividing strips was slightly off after I took the photo, but soldered joints can be re-set thankfully. I find that hiding the join when letting material in like this to be quite difficult, hopefully it won't look too bad once painted (half inch brush twenty year old pot of 'umbrol...).

I also scribed some panel lines onto the bonnet sides, using a scrawker;

The bonnet top panel had panel lines etched onto it already.

The very nicely etched grills are shown on the instructions as fitting on the outside of the bonnet. I decided that they'd look neater fitted from the inside;

I scribed a couple of lines inside the bonnet to help me get the grills level and central over the openings.

When folded up I found that the sides were about half a millimetre too deep, so once the bonnet assembly had been soldered up I filed the bottom of the sides down to suit the front panel.

Almost complete;

I'm unsure whether to add an exhaust or not, I quite like the clean lines and I'm reluctant to add anything else except of course couplings.

Although a works plate on the front might be a worthwhile addition, Narrow Planet list a 'Bagulay-Drewry' plate which would suit. Or perhaps a made up company?

With chassis and roof;

Somehow I think that it would have looked better with slightly larger wheels and a shorter wheelbase. But I'm not changing anything now.

All soldering done with my Antex XS25 and 145 degree solder, except the dividing bars on the bonnet sides where 188 degree solder was used.

Cab interior next.

Paul.

Another A1 Models diesel - part 4 cab.

Finally, onto the actual kit!

Before I did anything else I marked out the handrail and door handle positions on the cab sides, and drilled them .45mm.

Note the jewellers loupe (eyepiece), one of my favourite tools as I use it not only for marking out but for inspecting soldered joints and paint jobs. I favour the 'MRJ method' of marking out, using a sewing needle in a pin chuck instead of a traditional scriber and the loupe and a small drill (typically .45 or .5mm) to drill a start hole rather than use a centre pop. See 'Marking out a hole' by Mick Moore in issue 205. If that sounds a bit overkill, remember that wonky handrails can spoil a model. I also drilled holes for door handles at this stage.
Handrails and door handles were made from .45mm brass wire and fitted before the cab was soldered to the footplate, which made life easier as I could get the iron in from either the top or the bottom, and also get into the cab with flush cutting snips and a file to remove most of the handrail stub from inside the cab. I want to fit interior detail later on. Also note the two 'tabs' attached to the cab front and back sheets, these are made from scrap etch and are for the cab roof to be glued to after painting.

The roof has been folded up and the inner fold lines strengthened with solder. Rainstrips have been added as well, from .33mm brass wire, a small detail but one that I find quite satisfying.
I made the cut-out in the cab front a bit bigger, to help clear the motor wires.

Soldering the cab to the footplate took several attempts, tacking it in place, checking it, re-positioning it, before I was happy. For this I used 145 degree solder, the lower temperature needed being less likely to upset any of the footplate joints. In hindsight I think that I should have stuck to 188, as I find 188 flows better than 145.

Here it is in place,

And with the chassis fitted;

Its starting to look like a loco now;

Bonnet next.

Paul.

Another A1 Models diesel - part 3 footplate.

As I've scratchbuilt my own chassis rather than using the recommended Kato tram unit I've had to make up a replacement footplate. This does gave me the opportunity to slightly shorten the loco, hopefully improving the proportions. One thing that I was keen on from the start was that the loco would be inside framed, purely because I want to see the wheels on the train go round and round. Well, I did make them myself! And it gives the loco a slightly continental look, which I like.

The main footplate and the bufferbeams are cut from 1" x .016" brass strip, chosen simply because I had some in stock. Side and inner plates are from 8mm x .3mm strip.

I decided to cut out footsteps in the rear sideplates, which I made 4mm x 2mm, a scale 12" x 6", hopefully adequate for a 4mm scale foot to use safely. I first marked out the step, drilled a couple of 1.8mm holes then used square and triangular needle files to open out the steps to the correct size, checking all the time with a jewellers loupe. I did this before cutting the part from the strip of brass. It took no less than 4 attempts to make 2 that I was happy with. I didn't bother with front footsteps...
Valences are 1mm square brass strip, for strength.

I don't enjoy trying to solder brass nuts to footplates, so instead I used 2mm x 3mm brass strip, cut to 8mm long, drilled and tapped 10BA. The drilling and tapping was done before the piece was cut to length. There's more metal, which makes a better join, and its much easier than messing about with nuts and cocktail sticks...
Footplate and chassis together;

All soldering done with my trusty Antex XS25, 188 degree solder, and Eileen's Strong Flux.

Cab next.

Paul.

Back spindle steady for the Unimat 3.

When turning the end of a long length of rod, longer than the headstock spindle, some means of supporting the back end of the rod becomes desirable. This is to stop the rod running out of true, handy when turning journals at both ends of a roller for example, and to reduce any vibration from the unsupported end affecting the workpiece. As well as to stop the end hanging out of the back flapping around when using thin rod.

These steadies are simply turned from whatever material is to hand, in this case brass;

They are made a light press fit into the spindle. I drill them out to .1mm above the size of the rod that they are used with.

In place;

And in use;

Obviously when using bar this long in a Unimat 3 then the belt cover cannot be opened or shut, so I leave it open.

I used to use these a lot when I worked as a turner, not only for turning rollers as mentioned above, but for production work when several parts are turned and parted off from one piece of bar, which is why I use them on my Unimat.
Again, this is something that can be adapted to any lathe.

Paul.

Another A1 models diesel - part 2 chassis.

This is my second home brewed 009 chassis, and in the main the chassis follows on from the my first attempt at a scratchbuilt 009 chassis, seen here.

The frames are made from 8mm x .3mm brass strip, two sides being soldered together so that they can be drilled for the axle bearings and spacer locating holes. Bearings were turned on the lathe as were the spacers, lathe ownership does of course mean that I can produce the parts that I want and not rely on commercial sources. These spacers (6mm wide) are both drilled through and crossed drilled so that they can be used to hold body and chassis in close harmony as well as hold both frame sides together for soldering. Here are the frames clamped together, bearings soldered in place, ready to have the spacers soldered up once I'm happy that everything is nice and square;

Note the lengths of 2mm dia. silver steel being used to check that both axles are in perfect alignment (I'm using 2mm axles).
However, when I test assembled the chassis with the layshaft loosely supported by the motor and bearing mounts it became obvious that fitting the layshaft into the chassis was going to be rather difficult...

I didn't allow for a spacer being in the way. Ideally I want to be able to assemble the layshaft before sliding it through one end, the worms being small enough to fit through the front bearing hole, which is drilled 4mm, to suit the roller bearing that I'm using at the pulley end. My solution was to remove the turned spacer from one end and replace it with one made from brass strip, suitably drilled to attach chassis to footplate. Here's a pic. of the modified chassis frame, next to the front motor and layshaft bearing mount and rear bearing mount;

With the layshaft and axles in place, complete with gears, the front and rear mounts can be tacked in place. The gears need to be fitted at this stage to check that they're meshed correctly. To stop any stray flux corroding the steel axles I smeared them in oil. Once I was happy with the position of the mounts the layshaft was removed (slid out through the front mount) and the mounts soldered up. I did manage to solder up the front mount slightly wonky, but the beauty of soldering is that any joint can be adjusted.
Here's the chassis with the axles and layshaft trial fitted;

After I was happy with everything, I did double check with the gears re-fitted after the mounts were soldered in place, I added two little triangular strengthening brackets (made from scrap etch) to the motor mount to stop the motor vibrating. This is a problem on my first chassis, it doesn't affect the running but the the unit is noisier than I would like. At the same time I soldered in a spacer in the middle of the chassis to hold the pick-ups in place;

The mounts and pick-up spacer are made from 6mm x .5mm brass strip.

When I made the wheels I drilled them out to 1.9mm, I wanted a light press fit on the 2mm dia. axles so the plan was to broach them out to just under 2mm. This method has so far worked well on previous locos, which have had axles varying from 1mm (Kato) to 1/16" (Saltford) diameter. This time though I had trouble, two of the wheels had a pronounced wobble*. To remedy this I took the drastic step of mounting the wheels in a collet and drilling them out to 3mm. Then I turned a length of brass bar to 3.05mm and pressed a wheel onto the end. After a quick check that everything was concentric I drilled the wheel to size and parted it off. Repeat for the other wheel. Again they were broached to a press fit. My thoughts now turn towards drilling and reaming wheels 1.5mm and using 2mm axles with the ends stepped down to suit. This would also set the back to back.
Once the wheels were in place and I was happy I assembled the layshaft;

The roller bearing at the pulley end was simply glued into its mounting hole with cyano. There's a tiny spacer between that bearing and the pulley, one of the smallest parts that I've turned measuring a mere .4mm long. Gears are Tenshodo.
The motor is epoxied to its mount. Its a little Chinese 12v job bought for less than £2 a pair off eBay, measuring 7 x 16mm with a 1mm dia. driveshaft. They were so cheap that I bought 10, and this is the first time that I've used one. Nigel Lawton pulleys and drive belt are used, 1.2mm root on the motor, 4mm root on the layshaft coupled together by a 6.5mm ID belt.
The completed chassis;

Pick-ups are always a pain. A piece of copperclad sleeper is epoxied between the wheels, with the pick-up wire formed from 36swg (.193mm) phosphor bronze wire (from Eileen's). Solder the pick-up wire on the pad with 188 degree solder. Then the motor wire with 145 degree. And the pick-up springs off, heading for the carpet... Continue, holding everything in place with bits of wood, tweezers etc, until the job is done and the air has turned blue...

Before wiring the chassis up I held it in a vice and applied power to the motor leads, letting it run for an hour or so, making sure to change speed and direction a few times. The motor seems to perform well, although there is some vibration and noise, which isn't a problem and is what you'd expect for something that costs under a quid. It would be interesting to compare one with a higher quality job. Once the pick-ups were installed I ran it around my oval of Kato Unitrack (I don't own a layout). It ran well from the start, and continues to improve. I took it with me to a recent narrow gauge show where Will King very kindly gave it a test run on his layout (I was keen to see how it went through points), and again it ran smoothly. All very promising for future builds.

Footplate next.

Paul.

*In the previous two examples (Kato and Saltford) the bore diameter was smaller than the bore length, on these wheels the bore diameter and length are the same. A five sided tapered broach was used. Could the problem be in the relationship between bore dia. and length when using a broach? Hmmm.

A headstock internal stop for the Unimat 3.

Recently I took on the job of sorting out some axles for a friend. He had a model railway loco kit in the pipeline, and had been let down by a supplier. The job involved cutting a lot of axles from 1.5mm silver steel and facing them to the required length. To save myself a lot of measuring I made this little timesaver;

The main part is brass, with a length of 1mm silver steel rod as the stop. It fits into the headstock spindle;

Once in place a chuck can be fitted;

I've left the collet and closing nut off for clarity.

Each axle was cut overlength with a junior hacksaw, then held in a collet whilst being pushed up to the stop. Then the axles could be faced to length, all using the same setting and without the need to check and measure each one.

Of course this is meant for a specific job, I'm sure that an adjustable one using threaded rod could be made if required. I had to use 1mm rod as part of the stop rod sat inside the collet, each axle being 16mm long.

One thing to note is that collets tend to pull the job into the chuck, which did move the stop rod slightly, despite it being Loctited in place. On any production job checking every few, or every hundred or so, parts is necessary anyway. At least if the stop if moving inwards then work will be overlength, and easily put right.

This simple little tool saved me a lot of time and effort, and the basic idea can be adapted to almost any lathe.

Paul.

Saltford Peckett re-paint.

A long time ago (early nineties) I built a pair of Saltford Models Pecketts, seen here. The first one built, the red one, has always been my favourite 009 loco. The second one, the green loco, was never finished as I stalled at the painting stage. Both locos were brush painted, I didn't own an airbrush back then and never used aerosol primer either. For the green loco, the subject of this blog post, I used acrylic paint, unusual back then as most railway modellers still used enamels. Unfortunately the paint was a bit thick, and the finish poor. So I left it alone for the next twenty five plus years...

A couple of weeks ago I decided to remedy the paintwork and finish this one off once and for all. The first stage was to rub down the old paint using rubbing sticks and a fibreglass brush. Saltford locos are built as one piece, there's no seperate body and chassis, making painting rather more interesting than usual as the moving parts need to be carefully masked off, in this case with Tamiya tape and toilet paper shoved in the cab to protect the motor;

Red oxide car primer came first, for the buffer beams, which were then masked off so the rest of the loco could be squirted with grey primer;

I did have to do a bit of filling and rubbing down in a couple of places, primer is great for showing up small imperfections.
The bufferbeams could then be painted with Revel 330 'Fiery Red', which is the same as Humbrol's 'Signal Red'. I then tried to paint the roof black, firstly with Tamiya's 'Nato Black', then with Phoenix Precision's 'Dirty Black', but couldn't get a decent finish with either. So I masked of everything bar the roof and sprayed it with Hycote black primer. I would rather have used a muckier black but a poor finish on a roof would be very noticable, and I didn't want to get the airbrush out of storage (the rest of the loco is brush painted).

For the bodywork I decided to go for a blue, in this case Citadel's 'Altdorf Guard Blue' (I love the names Games Workshop use!). Frames are Phoenix Precision 'Dirty Black', ok on the footplate as there are no large flat areas to cover, and the footplates are expected to be a bit scruffy anyway. Buffers share the same pot of black, and were glued in place after painting. Testors Dullcote provides protection and tones the paint down. I couldn't decide how to finish the connecting rods, I was thinking of red as per my first loco or leaving them bare (they are whitemetal castings) but I instead chose Vallejo Model Color 'Oily Steel' despite having an aversion to metallic paint. I think I made the right choice.

I did a little bit of extra work on this loco back in the day, the cab sides and back have been reprofiled to allow for handrails to be fitted, and whitemetal springs were fitted above the front wheels. These are Chivers Finelines castings, bought from their trade stand many years ago. I also added some pipework under the saddletank, from brass wire, scraped clean of paint after finishing. Nickel silver wire was used for the handrails, and staples made good lamp brackets. I also fitted brass axle bearings and an LH17 motor instead of the cheap Mabuchi, complete with a flywheel that I turned at work, when machining payed my mortgage.

I made new flycranks for this loco, described here, but lost them and had to make two new ones. Such is life. Anyway, my two Pecketts posed together;

Unusually the con. rods are retained on the flycranks by slivers of plastic sleeve, slipped over the crankpins, and the rods slide along fixed 'pistons' which are glued into the cylinders, using split pins fitted behind where the cross head should be. Simple but surprisingly effective.

There is another one of these characterfull little kits waiting to be built...

Paul.

Another A1 Models diesel - part 1 introduction.

A while back I turned up some insulated wheels as an experiment. In fact I made a full set, two insulated and two solid metal, so that I could use them in a chassis and test them properly. Well, if I was going to make a chassis then I'd need a body to go on that chassis, so after quick look at A1 Models ebay shop I chose kit no.70;

I quite like the modern design, spacious cab and sloping bonnet, and can see some potential for detailing. Its designed to sit on a Kato 11-103 tram chassis, which means that there's plenty of room to play with inside. By using a scratchbuilt chassis I'll have to make a new footplate, there is one supplied but its specific to the Kato product, in fact everything below footplate level will be scratchbuilt in brass. Bufferbeams aren't supplied anyway.
As the kit is semi freelance (based on a Baguley but with the bonnet altered), I have a free hand when it comes to the chassis and detailing the body.

I've made a start on the chassis, and I've already hit an unforeseen problem, which I'll describe in my next post.

Paul.