CF MRC

Presidential motion support.

I have been making the two brackets at the distal end of the slidebars. Our clever etching chaps would probably have had a few flicks of a mouse and hey presto all done! However, these ones were cut out of two sheets of 10 thou nickel silver well tinned together. The first photo shows the Macor blocks I use for holding items whilst soldering: they save the finger tips!

 

The design for the brackets was sketched out in my notebook, as can be seen in the second photo. They are quite complicated and will need to look like a heavy casting when complete. The pair of brackets were fretted out with a piercing saw, as can be seen in the third photo, with bits to cut out marked by cross hatching. The two brackets can be seen in the fourth photo, ready for bending. The bending lines were pre grooved with a fine slotting file (some of the design bits proved to be superfluous).

 

Once bent up into shape, the brackets were silver soldered on to the slide bars. They were spiked into a charcoal block and the slide bars rested against the end and then held down with some bent dress making pins shoved into the charcoal. The valve guide end was draped in wet tissue to prevent the soft soldered piston stuffing box from coming adrift. Very small pieces of solder and flux were placed on the ends of the bar and the whole lot heated to red heat, with the solder flashing nicely. This also served to stiffen up the bracket by filleting the corners.

 

Final photo shows the two sub assemblies. They have now been roughly fitted to the engine and I'll show the mounting when complete. The beauty of using silver solder is that it is very strong and soft soldered details can be put on without everything falling apart.

 

Tim

They would make a nice train on CF!

Tim

John Allison IIRC?

Maybe John modelled the Lickey, but I also modelled a 1:37 incline on my N gauge layout Gouldby for Caldecote. It featured a Big Bertha converted from a Minitrix 2-10-0, or more precisely, the goodwill of a Minitrix 2-10-0. It featured in the last issue of Model Railways edited by Roy Dock in the mid 70's. The layout was also used to illustrate the Graham Farish range.

 

Tim

Why was 6 scared? Because 7, 8, 9.

 

Tim (from Hertfirdshire)

The engine will perform much better with finescale wheels Valentin. My Johnosn single was originally made with n gauge wheels and spent more time going sideways than forwards. I think that the better fit of wheel to rail gives better traction in a small awkward engine.

 

Tim

Justin

Takes a look at model aircraft ailoron pivots and cranks for any mechanism. It's what we used fir the front turnout on the NLR electric lines. Pretty cheap and very reliable & adjustable.

 

Tim

I packed out the cylinders with an L shaped shim. The cylinders are now a bit taller and have the characteristic and conspicuous brake lever arm supporting bracket underneath. There is now just clearance, even with the overlong front coupling rod pins. One thing I have only noticed today is that there should be a very slight downward - backward slope on the cylinders: fortunately, this was easily accommodated by the slack on the fixing screws.

 

The motion support bracket will be next. It hangs over the front drivers and will be quite a large chunk of metal. I will soon need to bend out the front guard irons, otherwise Lord Prasident will plough up Jerry's track on Saturday!

 

Tim

Looks like you are having fun there Gareth. Where is the motor going?

 

Tim

With the mileages that our locos do, I am not convinced that Simpson springs would last long enough. However, we have used skids under our 0-6-0s for years. They work very well and are hard to spot if chemically blacked. The running gets better and better of course as the track gets cleaner and cleaner. The only down side is that they are bit vulnerable in storage, but can be easily tweaked. Axles need a bit of slack in their bearings, but over do it and CF will soon wear them out!

 

Tim

I do hope the photo above with the mini drill was staged, as anything that can cut through metal can also cut through flesh and bone, and those drills are notoriously prone to flying off fore & arft if not clamped down.

Probably teaching Granny to suck eggs, but I thought it worth mentioning for the younger viewers who may be watching

Stuart, point well taken: the photo was obviously staged, otherwise I couldn't have taken the photo! However, you will observe that the blade is below the metal sheet and so could not jump over the top towards my thumb. Also I only use such powered instruments with very significant finger rests to lock one hand against the other, limiting any potential run away, as shown in earlier posts with hand instruments.

 

Tim

Water tank now completed.  

 

And a couple of shots of it in situ with 391 about to top up :-

 

water tank #5.jpg

water tank #6.jpg

 

Still to be fixed in place and bedded in.   I'll probably try and get it a little nearer the turntable to give a little more clearance between the corner and the track leading to the exchange sidings (in the foreground of the last picture).

 

Jim

Looks like your engines like peaty water Jim!

 

Tim

A star ship.

Having sweated on the piston rod stuffing box I have now ended up with two mini starships. I have left the slidebars closed together for mutual support- the motion support bracket will sort this out when it's made.

 

Once on the engine it is evident that a little bit more side clearance would be useful. I can easily pack out the cylinders by 10-15 thou and still be well within prototype loading gauge. This will also allow a representation of the brake operating pivots and levers between the frames. The front coupling rod pin will not have a collar on it.

 

I think I have worked out how to make the crosshead: it will involve some metal origami.

 

Tim

Silver soldering

For strength and convenience, the slidebars / lug joint needs to be silver soldered, as the piston stuffing box will be soft soldered to the bottom of the lug. For silver soldering I use a borax flux, easyflo silver solder and a small gas torch - as can be seen in the first photo. The components are held by pins in a heat resisting mica block with other carbon blocks to also act as heat shields.

 

The assembly photo shows the components held in place with a pin, running through the valve guide. The area is fluxed with the borax paste and a very small piece of solder cut and placed in the flux near the joint, out of sight at the back. The components are then heated up with a flame and the solder flashes into the cracks - simples! The secret with silver soldering is just using the right amount of solder.

 

The final photos show the assembly after cleaning up. The slidebars are currently very delicate and desperately need support at the back. Next job will be to make the piston stuffing boxes and then the cross heads and piston rods. As always, the camera is rather cruel.

 

Tim

P2 rear valve spindle guide and slidebars.

These are quite tricky pieces, as they are fixed to each other. For construction purposes they needed to be removable from the cylinder. I therefore turned up some brass bits to give me enough meat to whittle out the correct shape for the valve stuffing box and guides as well as a lug into which the slidebars would be soldered. I made three - the second one was a tad too small and was not an interference fit in the cylinder.

 

The slidebars were made from thick steel sheet, with the slot cut out using a fine diamond disc, as can be seen in the second photo.

The slidebars were filed down to shape and slotted into the lug at the bottom of the valve spindle stuffing box (third photo).

 

Tim

Seeing a realistic train move through a realistic scene as a three-dimensional painting has always been what floats my boat. Fortunately, we all live in a very broad church!

 

Tim

It depends on scale. We used to run very long trains on Chiltern Green and the scenic scope of the model easily accommodated them, as you could stand back and see them in context. It is more difficult to do this in the larger scales because you can't stand back far enough (unless outdoors).

Tim

If they were Jidenco origin, you deserve a medal! Look forward to seeing everyone on Saturday in St A.

 

Tim

I went to school with Andrew Kinsella's son, Keith.

 

Tim

Another diversion was an attempt to produce a scale (ish) working street/platform oil lamp. Every commercial working N gauge lamp I've seen has been hideously over scale. I didn't fancy trying to rig something up with surface mount LEDs in the lamp itself, but it struck me the Ratio lamp moulding, which is mainly solid translucent plastic, could be used with fibre optics.

I replaced the post with an equivalent length of 1.5mm OD, 1mm ID brass tube, and wrapped around, tweaked and soldered some 0.4mm wire to represent the wrungs at the top. I then ran a 1mm fibre optic up the middle, roughed up the end that sat nicely inside the moulded lamp, and connected it to a flat topped warm white LED with heat shrink. The result isn't terribly bright, but then the real thing wouldn't have been either, I don't imagine? The closest resistor I had to hand was 1K (working from 9v battery) so imagine I could make it a tad brighter by swapping this for a lower resistance one. I did consider trying to find even thinner tube and optics, but I imagine the result would be even dimmer? Here's the works

IMG_20151231_165650small.jpg

Happy New Year!

Justin

All your lamp post now needs is a Victorian 'lady' standing under it! I think you could make the post a bit finer if you tapered it with a few strokes of a file, maintaining a 1.5 mm o/d X 6 mm high base. You have 0.5 mm to play with and it only needs the goodwill of the metal at the top. Think yourself lucky that we won't be putting in an order for 3 dozen on CF!

 

Tim

I have now completed the rear running plates on the P2. Gresley engines with this type of running plate have a small step between the cab floor level and running plate over the wheels. The front running plate finished just short of this position. In one of those jobs where things fall into place quite nicely, I bent up the step as an extension of the rear running plate (as can be seen in the first photo): it also does a good job of masking the joint. Of course the clever etch designers would probably have made this all from one piece, but scratchbuilt components are generally better made in penny numbers (at least they are with me).

 

Soldering this assembly in place was a bit tricky as the engine is a very good heat sink. It was of course tinned with 144 solder and then held in place at the front end with a little self-locking clip, as can be seen in the second photo. The iron needed plenty of solder on it to make a good heat transferring area with loads of phosphoric acid flux in the region. It was laid up next to the valence and runny plate and set at maximum temperature - 450 deg C. When all the solder was flowing well the iron was removed. There was quite a bit of solder to clean up, but I think the final running plate and step looks the part.

 

Tim

Teaching is a fascinating hobby: I am really am not concerned about what is said of the profession - we all know someone who has inspired us. I get great pleasure from teaching hand skills to people from all walks of life. Putting in the theory behind it all is also a challenge, but again very worthwhile. In 33 years of teaching I have only found two individuals who simply couldn't develop adequate manual dexterity (or as one of our technicians used to say "the students need to get manual dexterity with their hands"...). When you have an individual with a strong artistic tendency, then the results can be outstanding.

 

The beauty of model railways is the ability to combine pictorial artistry and engineering: not many practical hobbies allow that, especially when you have a project involving a group of individuals all contributing to the greater whole.

 

Tim

Up market Brio?

 

Tim

Pictures of the modified articulated Japanese tram mechanism for the tube. Basically, all of the top hamper was removed to fit into the loading gauge, copper tungsten weights were fitted over the bogies and some substantial wiper pickups installed (110% reliable). The wheel standards are irrelevant as there are no turnouts.

 

Tim

Mark

The B Type bus was completely scratchbuilt in Plastikard, using an early photocopier for the advertisements and destinations and office staples for some of the metal bits.

 

The tram was also by Matthew and skids along on solid acetal 2mm scale wheels moulded by Denys Brownlee as replacements for Peco wheels. It is actually the second tram, as the original (at that stage only the lower saloon) was nicked at the first time we exhibited the layout at Horticultural Halls in the mid 80's. Every few years it needs a new set of wheels. It is magnetically coupled to a massive mechanism under the road (also made by Denys) that has five wheels: the large fifth wheel is in the middle, is rubber tyred and runs on a strip of emery paper. The gauge is equivalent to Irish broad gauge in 3/16th scale, with substantial sprung copper wiper pick ups running on the circular steel rail. The tram has one magnet (N) and the mechanism under the road has three (NSN) to centre the vehicle above it in the road. The road itself is thin PCB with the code 40 FB rail directly soldered to it. No one seems to notice that it only goes up and down the same length of track. It is usually the most reliable part of the layout and must have covered hundreds, if not thousands, of miles over the years. I have one of the Oxford diecast trams, but that is very disappointingly crude, especially at the top. Might be OK with very major surgery.

 

I converted the STL from a white metal kit (might have been a Beaver RT). The other buses are from solid clear resin castings, very subtly made by Ced Verdon. On the North end of York Way we have an indeterminate 1:400 bus headed south, sourced from architectural suppliers.

 

The tube was completely scratchbuilt by Stewart Hine using a power bogie with an armature from a Z gauge mechanism. This was replaced by a Japanese tram type mechanism this year (much cut down and modified) coincident with a major simplification of the underground layout. This has to be 110% reliable and previously it had not been. My four year old grandson had great fun 'driving' it at the last AP show!

 

 

Tim