Brian Madge Alice class Hunslet part 12 - turning a new dome.

Velinheli has a nice brass dome cover. The kit comes with a whitemetal casting, which I have to say is rather an odd shape, more pith helmet than dome. Now, nothing looks more like brass than brass so I made a rough sketch, found an offcut and set to work. I don't have a drawing of V. with dome so to get the dimensions needed I scaled a photo, as described here.
The end of the bar, which will be the base of the dome, needs to be filed to suit the top of the saddletank. I started with a half-round needle file, roughing out the shape whilst comparing it to the casting. Once the shape was reasonably close I 'blued' the filed end with a marker pen, wrapped a piece of fine wet+dry paper around the tank and gently rubbed the blued end along it. Any high spots were highlighted by the emery paper removed the blueing, the high spots then being gently filed and scraped away (with a three-sided scraper) until all high spots were removed and the end sat nicely on the tank top;

Its worth taking time over this part, as any gaps between dome and tank would stand out and look awfull.
Now the bar could be held in the lathe and turned. First of all I turned down the flange dia. (7.7mm), then using a round-nosed tool turned the main body down to 5.9mm dia. A 2mm hole was then drilled to 3.5mm deep;

The workpiece was then removed to the workbench, and the flange sides filed to shape using a round needle file, strips of fine wet+dry paper, and plenty of care;

Again, time and patience is needed for a good result.
After returning the workpiece to the lathe and parting the dome off a short length of 2mm dia. rod could then be soldered into the drilled hole;

This not only allows the dome to be held in the lathe for final finishing but also locates the dome on the tank.
First of all it was faced to length, then a .7mm hole drilled in the end, before filing the top to shape. A short piece of .7mm rod was cyano'd into the end, to represent the top fixing bolt, and rounded off with a file. Rubbing sticks were used for finishing;

Model engineers and Unimat enthusiasts would no doubt be horrified by my use of an ER16 collet in an E16 holder!

Now with the 2mm rod cut down, here it is on the loco;

And next to the supplied casting;

Paul.

Brian Madge Alice class Hunslet part 11 - boiler, cab sidesheets and steps.

Each cab sidesheet is made up from 4 parts, an L shaped backing sheet; half-etched overlays , for the rivet detail; then an L shaped top plate. An alternative one-piece half-etched sidesheet is provided for those locos with rounded cab corners, but no rounded top plate.
Here's the sidesheets, on the right the overlays are soldered in place;

I left the top plate still attached to the etch sheet which made soldering the sidesheets to the top plate easier;

Then I soldered one side onto the footplate along with the handrail (.5mm brass rod). I had the idea that I could solder both sidesheets in place then glue the boiler between them, but as the top of the sidesheets curve inwards to suit the tank profile that didn't work...
So I soldered the boiler in place instead. First of all I tinned the footplate where the boiler would need to be soldered with 188 degree solder. Then I used Carrs 70 degree to tack the rear of the boiler in place from the underside. After checking all was good I used a little chip of solder to make the front joint where the front edge of the smokebox meets the footplate. Then the rear could be finished with a dab more solder. This went exceedingly well, I haven't soldered whitemetal for over 20 years, prefering glue (I don't subscribe to the view that all metal to metal joints have to be soldered), and I've never soldered whitemetal to nickel silver or brass. I used my 25w Antex and Eileen's Strong Flux. Here it is prior to cleaning up;

Note that the smokebox rivets have been filed off, I've done the same to the tank sides. All will be replaced with Archers transfers.
Here's a cruel side view with both cab sheets in place;

Note that the footsteps have also been soldered on. On some quarry Hunslets including Velinheli the backplate of the step has a semi-circular cut out, possibly a local modification to allow access to something or other, easily replicated with a rat-tail needle file. For some reason the etched step has a fold down lip at the bottom not seen on the prototype, I've left it as intended for the moment as it will add strength to an otherwise vulnerable area.

The smoke box door, which needed minimal fettling,  is just epoxied in place after drilling out the centre ready for a dart to be fitted;

Now I can start thinking about detailing.

Paul.

Brian Madge Alice class Hunslet part 10 - turning a new water filler.

A while ago I turned some Austerity sandbox fillers from brass. Although they looked fine they were made from solid bar and I wasn't completely happy with the handles, which on the prototype is a rounded knob. As they sit tucked away under the tanks I'm not too worried about their appearence but I was sure that I could improve things. So I decided to try a different approach and made up a new water filler for my OO9 quarry Hunslet. There's nothing wrong with the cast filler supplied with the kit, I just decided to make something finer. On the prototype the cap is only slightly bigger than the flange and the whole assembly has quite a low profile.

The first job was to shape the knob. I held a short length of .7mm brass rod in a collet and attacked the end wth a triangular needle file to make a rounded shape;

Please note that bare brass is a pig to photograph! Click on the photo for a larger image.

I then filed the end of a length of 4mm dia. brass bar to suit the saddletank, then turned the end down to 3.6mm dia. by .5mm long. A .6mm dia. hole was drilled in the end, which was then gently countersunk, and the filler parted off to .8mm long;

The two parts could then be soldered together after opening the hole out with a broach until the .7mm rod just fitted, the solder sitting in the countersink;

On the left can be seen my first attempt, which I decided was just too fine. The lower flange section was turned down to 3.75mm dia., and I felt that whilst it looked good close up the lip of the cap would disappear under my usual rubbish paintwork. Here's the final cap in place, with the supplied casting sitting in place of the dome;

I know that some would view the above as a complete waste of time, especially as the rounded knob is hardly noticable at 'normal viewing distance' (whatever that is) and that there's a perfectly acceptable casting supplied, but its been another enjoyable exercise which I've learnt from. And that to me is the whole point.

Paul.

Brian Madge Alice class Hunslet part 9 - positioning the boiler fittings.

The boiler/saddletank casting needs to be drilled for the boiler fittings, that is the chimney, water filler, dome and safety valve assembly. Of course the casting is suitable for a variety of different small Hunslets, some of which had domes, and some of which didn't, so casting dimples for the filler and dome would mean that the dimples could be in the wrong place according to the loco modelled. I'm modelling Velinheli, which is fitted with a dome.

To find the correct postion for the filler and dome I had to do a little maths...
I started by finding a good side view, luckily there's an excellent photo in the April 2013 issue of Railway Bylines (volume 18 issue 5).
I took the measurement of the top of the saddletank from the photograph, then divided it by the measurement of the model's saddletank to give me a ratio to divide by (133 / 23.7 = 5.61).
Then I measured the position of the centre of the water filler from the tank front on the photo, and divided that by that ratio (36 / 5.61 = 6.42).

The same was then done to find the dome position from the tank rear (45 / 5.61 = 8.02), and the position of the safety valve, which is slightly offset to the rear.

Now I had the relevant measurements I could drill the casting, easily done with the Unimat set up as a drill press and the casting held in a machine vice;

Well, if you've got the tools use them!

Here's the boiler fittings sitting in place;

 

Note that the dome and safety valves have yet to be properly fettled and seated.

My apologies if my terminology is incorrect, but I'm not a mathematician! Comments welcome.
I'm also aware that I could have just set the dome and filler positions by eye, but this has been a usefull exercise.

Paul.

Brian Madge Alice class Hunslet part 8 - handrails and couplings.

I wanted nice discreet Bemo style couplings for this model, large couplers would look wrong and spoil the lines of the loco. Mark fitted Greenwich etched couplers to his, which suit this size of loco well, but I wanted something even smaller especially as I intend fitting wooden side buffers as well.
I chose RT Models etched couplings, without loops, soldered to the bufferbeams by bending the tail of the coupling through 90 degrees to give a large surface area for the joint;

 Another thing that I wanted was fine handrails and stanchions (knobs), so I'm using Markits 'N' gauge stanchions and .33mm wire. These are straight rather than shaped but I feel that standard 4mm scale stanchions can look overlarge on such a small locomotive.
Before the boiler is fitted to the frames I decided to mark out and drill out the holes. The first job was to measure the height of the stanchions, where they seat on the saddletank, using the drawing from the Cliff Thomas book. Then the measurement could be transferred to the model using a scribing block;

The casting is sat on a parallel block for convenience.
Then the hole positions could be added, a scale 3" from the tank ends, and the holes drilled .4mm. To make sure that all of the stanchions sit at the same angle on the tank edge I sat the casting in a V block and used a pin vice held upright to drill 4 holes at 45 degrees;

Velinheli's handrail continues around the chimney, so a length of .33mm wire was bent to suit, threaded through the stanchions, and the whole assembly taped in place, using plasticard offcuts to space the handrail away from the boiler, like so;

Then I used a tiny amount of solder paint and a light touch with the iron to solder the wire into the stanchions (but not the stanchions into the casting!). After trimming the excess wire away from the firebox end the handrail can be sprung out and put away until after the model is painted.

Here's the boiler sat on the footplate, handrail in place;

Note that the rivet detail has been removed from the boiler sides, the rivet pattern on Velinheli differs from the casting and will be added after priming using Archers transfers.

Obviously I've used a few tools here that won't be in many modellers toolbox, the only reason that I own V blocks, parallels etc. is because I once worked in machine shops. Please remember that this blog is about how I do things, not about how you should work!

Paul

Brian Madge Alice class Hunslet part 7 - turning a new chimney.

I've turned myself a new chimney for my Brian Madge small quarry Hunslet. There's nothing wrong with the casting supplied with the kit, but as I have a lathe and enjoy making things on it I decided that turning up a chimney would be an enjoyable way to spend a morning. Its also a way of adding a personal touch to the kit, and a turned chimney always looks better than even the finest casting.

The first job, as always, was to prepare a simple 'fag packet' sketch, dimensioned in millimetres, from the drawing in Cliff Thomas' excellent 'Quarry Hunslets of North Wales'.

This time I decided to take a different approach to forming the bottom flange, so I hand filed the end of a length of 5mm dia. bar to suit the smokebox, not too difficult as long as care is taken and the hand remains steady;

Of course this would be harder work if making the chimney for a larger loco, probably requiring fly-cutting.

The actual turning of the chimney was basically the same as for the Waril type, apart from leaving the bottom of the flange solid and the shape of the top cap, which is convex above the lip and concave below. The top of the lip was formed with a file, and the lower part formed using a round-nosed tool (as was the bottom flange). The bottom was also drilled with a 1mm drill so that it could be pinned to the smokebox. Here it is ready for the next operation;

Note the flat sections seen at the top and bottom of the smokebox flange, these needed blending in with a round needle file. So the turning was now removed from the chuck before parting off to make holding the chimney easier when filing.

The filing itself was just more steady work with a fine needle file and wet+dry. I wrapped a piece of masking tape around the parallel section to protect it from stray file marks, and checked the work regularly with a magnifying glass;

Once I was happy with the shape the chimney could be re-chucked in the lathe and parted off. The next job was to drill it out from the top. To do this I held it in a split mandrel (7mm dia. brass, skimmed over the top and drilled to suit the centre section of the chimney, then cut in half down the centre with a razor saw and parted off) and drilled it out to 1.8mm dia., 7mm deep;

And here's the end result, along with the supplied whitemetal casting and the split collet;

And placed on the loco;

Those that know a little of the history of my model will be interested to learn that the damage inflicted upon it (cab backsheet snapped off!) has now been repaired.

Paul.

Brian Madge Alice class Hunslet part 6 - cab rearsheet.

The cab rearsheet comprises of 8 seperate parts including the two handrails. The main sheet has a flat rail soldered onto its top edge, to work out the best way of soldering this in place took plenty of time and thought!

I decided to solder the back sheet to the rail whilst the rail was still attached to the etch. I clamped the etch between an offcut of thin MDF and a piece of 6mm x 12mm stripwood (64p from B&Q), the stripwood being positioned in such a way that the backsheet sat over the rail ready for soldering (it looks a bit messy in the photo below but cleaned up nicely);

The solder, 188 degree as usual, didn't want to flow into the joint at first despite carefull preparation, I suspect that the heat from the iron leached resin from the wood contaminating the metal. The solution was to tin the rail first then solder the backsheet in place. After making the joint and removing the assembly from the etch I ran the iron carefully along the joint just to tidy up.

To attach the rear sheet to the footplate I again used a short length of stripwood clamped  to the footplate to ensure a right angled joint, the clamp then being held in a vice whilst I made the joint;

 

I feel that half etched lines on the footplate and under the top rail would have made lining up the rear sheet easier.

Handrails were fitted next made from .5mm wire soldered in place. The etched holes in the footplate are on the large side, I would have prefered to use .45mm wire. Personally I think it would have been better if the handrail holes were etched undersized so they could be broached to size.
All of the above done with 188 degree solder.

Studying photos of these locos during their working lives shows that the rear doors were often left open, so that's how I've fitted them. Some locos had handles on the doors, some didn't, and the pattern of handle varied when fitted suggesting local modifications. Something to note if modelling a particular loco. I'm basing this model on Velinheli which didn't appear to have handles, but decent photos of the rear of these locos seem to be scarce.
After fitting the doors I soldered the runners in place, these are delicate 'L' shaped etches that measure .6mm x .3mm. I tinned them on whilst still attached to the main etch, then carefully cut them free and sweated them to the backsheet. I did manage to solder one in place upside down, easily done as they are very fine, however the beauty of soldered construction means that joints are easily undone, cleaned up and re-made.
Doors and runners after cleaning up;

For the doors and runners I used 145 degree solder.

Its getting there;

Next job will be the cab side sheets.

Paul.

Brian Madge Alice class Hunslet part 5 - crossheads and connecting rods.

The crossheads and connecting rods are, like the slidebars, machined from nickel silver. They are held together using 16BA screws and bolts.

The first stage after de-burring is to solder a screw to one crosshead half, I used 188 degree solder. I then filed the screw head down until the slot disappeared.  The instructions tell you to assemble the crossheads and con. rod onto the slidebars held together with a piece of blu-tack to aid soldering the second half of the crosshead in place. All good advice which of course I ignored. I just bolted the two halves together with the con. rod between them, made sure everything was square and that the con. rod moved freely and the crossheads slid easily along the slidebars, then put a drop of flux on the screw thread, placed a tiny chip of 145 degree solder on the thread then a light touch with the iron secured the nut without soldering everything up solid. (I did try soldering the nut to the crosshead - I managed to solder the whole assembly up solid and had to strip it down and clean it up. Thank goodness for desoldering braid! I live and learn...). The thread could then be cut down and the nut filed down as much as I dared.

Here's a pic. of one assembled crosshead/con.rod and the components of the second;

It was my intention to make both up together, but I managed to lose one crosshead half when it pinged out of my pliers across the workbench, never to be seen again despite a fingertip search of the surrounding area. Brian supplied a spare, which arrived the next day! Superb service!

A side view;

 

And from underneath;

Running just gets better and better, but then its done a fair mileage running around an oval of Egger-Bahn set track on the sideboard!

The piston rods are stainless steel pins and the advice is to glue the head of the pins to the crossheads with a drop of gel cyano, which I'll do during final assembly after painting.

Thats all of the mechanical work done now, time to decide which loco to model and think about the bodywork.

Paul.

Brian Madge Alice class Hunslet part 4 - cylinders and slidebars.

The slidebars are machined from nickel silver and are ready formed, which makes assembly easy as the hard work has already been done. A screw needs to be soldered in place to bolt the assembly to the frames, 16BA is provided but I found this to be a sloppy fit in the machined hole in the slidebar so I used 14BA instead, opening out the frame holes slightly with a 5 sided broach. Also 14BA is a lot less fiddly than 16BA! Then the turned brass cylinder can the soldered in place;

 

188 degree solder was used for the screw and cylinder.

Cylinder wrappers are half etched with a raised section on one end. This raised part is designed to poke up through a cut-out in the footplate and represent the top of the cylinder casting, which on the prototype can be seen sitting above the footplate either side of the smokebox. Although I can see why Brian has designed the wrapper this way, to make the entire cylinder including the top part in one piece, its a bit of a faff trying to not only line up the wrapper so that the top sits nicely in the footplate cut-out but also to form the wrapper so that the upper part can sit at an angle. So I've ignored the raised section and wrapped the overlays right round the cylinders;

 

Wrappers soldered in place with 145 degree solder.

I'll make up the cylinder tops later on with scraps of plasticard filed to fit into the footplate cut-outs.

Before fitting the cylinder/slidebar assemblies I had to cut down the 14BA screws. However, before I snipped the screws to length I fitted two nuts onto the threads, screwed down to the slidebars.Then the uncovered part of the thread was filed away until a nut would slide along it. The screws were then cut down leaving part of this filed section attached. The reason for this is simple - it can be rather fiddly trying to get a small nut to start on the end of a thread, even more so when that thread is difficult to get at i.e. between two frames. By doing the above the nut can be placed on the filed section where it will sit without falling off until you are ready to start screwing the nut down the thread. Hopefully this sketch will makes things clearer (click on the pic. for a larger image);

One assembly in place;

There are etched cylinder end covers still to be added, I'll epoxy these in place later on (when I've got some Araldite mixed up for another job).

Crossheads and connecting rods next.

Paul.

Brian Madge Alice class Hunslet part 3 - flycranks, coupling rods and bufferbeam overlays.

On the brass body detailing etch there are half etched overlays for the buffer planks, used to provide rivet detail. The rear overlay has a row of rivets along one edge, the instructions do not say which way up it goes but studying photographs of the prototype shows that the line of rivets goes along the bottom. These were soldered in place using my usual 25w Antex and 188 degree solder. Here's the front overlay in place;

Flycranks are machined in brass and are supplied with crankpins (16BA screws) already soldered in place. They are designed to be Loctited in place, both axles are gear driven so the coupling rods are cosmetic and quartering doesn't need to be precise.

I started by fitting the cranks to one side, checking for smooth running with a coupling rod fitted, then fitting the cranks to the other side, again checking with both rods fitted. I took my time and spent ages test running at every stage. Once I was happy the front crankpin could be shortened and the crankpin bush carefully secured with Loctite as below;

Clearences between the wheels, cranks and the frames are very tight;

 

I do wonder if the frames would be better etched in thinner (.015"?) material to provide extra clearence. However, once set up its a super smooth runner.
I had to offset the motor block slightly, to hold the block in place I've glued small plasticard pads onto the sides of the block where it meets the footplate (not seen in these photos).

I did have problems with the cranks, for some reason I had trouble getting the Loctite to 'grab' despite cleaning everything with a glassfibre scratch brush followed by lighter fluid. In fact one crank came loose as I was unscewing one of the crankpin nuts so I could cut down that particular crankpin. I refitted the crank with Rapid Araldite, if I build another one of these (highly probable, Brian does a cabbed version as well) I'll probably use Araldite rather than Loctite on all of the cranks.

Here's how the loco looks at the moment;

I'd get on with this kit a lot faster if I didn't keep spending time test running it, there's something about outside frames and flycranks that fascinates me.

Paul.

Brian Madge Alice class Hunslet part 2 - chassis running and footplate assembled.

It now runs!
The motor is simply glued onto the chassis block, I used Araldite Rapid, before Loctiting the small pulley in place in line with the layshaft pulley. (Motor and pulleys are from the Nigel Lawton range.) The motor was then wired up and test run, I ran the motor in for a while without load before fitting the drive band (a spare is provided) and testing the chassis on an oval of track. With a bit of extra weight on top it has proved to be very smooth and controllable.
Here's the chassis sitting on a 1p piece;

Note the resistor, this is supplied with the kit as the motor is a 10 volt unit, apparently it can be run on 12 volts with care but I prefer not to take chances! All of the exposed wiring is covered in a thin coat of epoxy to prevent shorts. Don't look too closely at my soldering, although I'm comfortable soldering etched brass and nickel silver the thought of joining two wires together fills me with dread!

The footplate, buffer planks and frame sides are etched in .020" nickel silver, which is quite heavy gauge for an etched kit but adds usefull weight. The frame sides include spring detail and slot through the footplate;

There are several small projections under the frames, the outer square 'tabs' represent gaurd irons which on the prototype are angled inwards, and the smaller 'tabs' represent the bottom of the brake hangers which can just be seen on the prototype, these are half etched. This half etching means that the frames are in fact handed, which is not immediatly obvious and not mentioned in the instructions. Alternative slotted buffer planks are supplied presumably for those wanting swivelling couplings.
All soldering done with my trusty 25w Antex and 188 degree solder and all parts fitted perfectly with the minimum of fettling, which was just a case of filing off the cusp.

The motor block installed in the footplate assembly;

 

The frames just rest on the axles.
From underneath;

 

Digging out my scale rule and comparing the frames and wheelbase with the scale drawing published in 'Quarry Hunslets of North Wales' shows them to be accurate in all major dimensions apart from the width which is a scale 5" too wide, probably to compensate for the overwidth (for this loco at least) one-size-fits-all track gauge that we use in OO9.

Paul.