7mm On Heather's workbench - a trio of JLTRT Mk2s

[Heather Kay]

I've officially started the 2013 7mm modelling season (finally), so I thought I'd share progress on what's happening on my workbench.

Currently, I am batch building coaches for Richard Carr. I've built four JLTRT Mark One coaches for Richard over the past couple of years, and he has now asked me to knock together three JLTRT Mark Twos. To be precise, I am building a brace of MK2b Second Opens and a Mk2c Brake Second Open. The coaches will be completed in BR blue/grey as they carried in the early 1980s. I deliver the finished and painted coaches to Richard, who then letters and weathers them.

I am starting the build with the wheels and bogies. Slater's don't produce a 3' plain disc coach wheel, so I am used the 3'1" 3-hole wagon wheels. A custom etched disc is glued over the front face, while the holes are filled on the rear.

The first stage was to chemically blacken the etched discs.


I used Birchwood Casey Brass Black, liberally applied with a cotton bud after cleaning each etch with an abrasive rubber. Each disc was then cleaned up with a fine file to remove cusps from the outside and inside edges. I have a thing about removing etched cusps.



All the wheelsets were degreased to remove the sticky tape residue used in packing, and checked for concentricity and back-to-back. I then used a sharp blade to remove the moulding pips from the backs of each wheel. I also twiddled a square needle file in each hole to give some roughness for the filler to grab on to later.



The inserts were superglued to the fronts of each wheel, trying to ensure the etched lifting holes roughly align on each side. The holes were bunged with Squadron White filler. Once they're dry, I suspect a second application of filler will be required to account for shrinkage.



The next stage is to clean up the filler, run a 0.9mm drill through each lifting hole (so you can see the little pinpoints of light as the coach runs by ), chemically blacken all the steel parts, and finally coat everything with my proprietary underframe gunge colour.

The next phase is to break open the B4 bogie bits, and see just how much cleaning up the castings will need this time.

 

[Dog Star]

I've officially started the 2013 7mm modelling season (finally), so I thought I'd share progress on what's happening on my workbench.

What is this? Starting a 2013 build without submitting the proposal to the official WT "What you going to build in 2013?" thread - official 'cos Jordan started the thread .

The next phase is to break open the B4 bogie bits, and see just how much cleaning up the castings will need this time.

Go on, be a sport... post a photo of the bogie castings as received .

Come to think of it... please post a photo of all of the other Mk.2 castings for those of us who might be so daft, silly, stupid, keen as want to build a Mk.1 with air brake and ETH fittings.

regards, Graham

 

[Heather Kay]

What is this? Starting a 2013 build without submitting the proposal to the official WT "What you going to build in 2013?" - official 'cos Jordan started the thread .

Um, I thought I did.

I certainly will show the castings as received. You never know, they might have remade the mould...

 

[Dog Star]

Um, I thought I did...

Just checking .

Uhmm the proposal was to "put together"... now we read that you are going to "knock together"... a quite different kettle of diseasel, need a different size of hammer .

 

[Heather Kay]

now we read that you are going to "knock together"

Synonyms, my dear sir, synonyms.

 

[richard carr]

Heather

I'm glad to see you have made a start on the coaches. Just to let you know that John Lewsey has some paint for you, both blua and gray, 3 cans of each. I have found that you need to spray quite close to the model to get enough paint on to get the whole thing wet and get a nice smooth finish. Its worth having a little experiment with before you start the coach sides.

Richard

 

[Heather Kay]

Thanks Richard. I'll contact John and see when he's likely to pop over.

 

[tomstaf]

I've officially started the 2013 7mm modelling season (finally), so I thought I'd share progress on what's happening on my workbench.

The next phase is to break open the B4 bogie bits, and see just how much cleaning up the castings will need this time.

Hi Heather,

Nice to see someone else having a go at the JLTRT MK2s. I hope the B4 castings in the kits are better than the ones I received. In the end I gave up trying to clean and straighten the casting out and used Easybuild's instead.

There are a few details that I wanted for mine so turned to etching. I had some passenger communication cord reset keys etched last year. These appear on the ends of each coach.



I've also got a few more parts that I'll be sending off to the etchers in the next couple of weeks - the rust strips either side of the doors (scales out at 0.9mm wide in 1:43.5) and the flat profile handrails for the BSOs. Let me know if you want any.

Cheers

Tom

 

[Dog Star]

I've also got a few more parts that I'll be sending off to the etchers in the next couple of weeks - the rust strips either side of the doors...

Only yesterday I asked Bob about the size of the visible portion of that strip on the Mk.1 carriages... I wonder if Bob's answer is applicable to Mk.2 carriages? (see the Mk.1 Resources thread)

I've also got a few more parts that I'll be sending off to the etchers in the next couple of weeks - the flat profile handrails for the BSOs.

You say BSO without saying Mk.1 or Mk.2 - maybe that distinction does not matter, in which case I shall be interested in those handrails for Peter's Mk.1 BFK .

regards, Graham

 

[tomstaf]

You say BSO without saying Mk.1 or Mk.2 - maybe that distinction does not matter, in which case I shall be interested in those handrails for Peter's Mk.1 BFK .

regards, Graham

All my parts are in relation to MK2s Grahame. MK1 BSOs have round or oval profile handrails, nothing like the MK2s so out with the wire for them me thinks.

Cheers

Tom

 

[Heather Kay]

I've also got a few more parts that I'll be sending off to the etchers in the next couple of weeks - the rust strips either side of the doors and the flat profile handrails for the BSOs. Let me know if you want any.

Thanks Tom. It's down to the client, really, so I'll check with him.

(He's probably reading this anyway and will let me know. )

The bogies. Well, where'd you start? What's that old saying? "If you want to get there I wouldn't start from here."



You know that feeling you get when a tax return is due? I have exactly that feeling on surveying these three bags of whitemetal lumps. I've been here before, of course, having constructed three sets of these kits for the Mk1 SKs. I can't say I am relishing the prospect, so the idea of an alternative is very tempting. It's down to Richard in the end.

To be honest, this batch seems to be slightly cleaner and in better register than before. Things are not perfect, certainly. There is a significant amount of flash to be cleaned up from the axlebox castings, in among all the fiddly bits, and from between the side frames. Parts need to be fettled to get a good fit before construction begins. I've spent about two hours cleaning up most of the bits for, let's see, how many? Ah yes, one bogie so far...



That bend is due to the camera. It's not as banana-like in real life!

Storing the many bits that make up a set of JLTRT B4s is made simpler by those plastic takeaway tubs they use instead of foil containers these days. One tub can hold one pair of bogies, even when they're finished, and when doing a batch like this I also letter/number each set and container. The coach bodies are numbered in the same way, so I can have three sets of bits on the workbench and know which bits belong with each other. Usually.



A supply of blunt scalpel blades, a butane torch and steel wire brush will be very handy in the coming days, I feel. This is the result after just a quick clean-up of the sides of one bogie.



Once the bits are cleaned up - assuming the client doesn't decide to go for Easybuilds in the meantime! - construction will be low-temperature solder. I'll explain that more when I get to it, sometime in February. I might well decide to tackle other mundane tasks for some light relief, such as cleaning up and painting the seat mouldings or completing the rest of the models...

 

[Dog Star]

A supply of blunt scalpel blades, a butane torch and steel wire brush will be very handy in the coming days...

Scalpel blades as scrapers I understand, steel wire wool instead of fibreglass brushes seems a good idea. Butane Torch? Now that has me stumped!

Please remember to post photos of the fittings for the air-brakes.

regards, Graham

 

[Heather Kay]

Butane Torch? Now that has me stumped!

For the stubborn whitemetal clagging up a file, run it in a flame for a bit to melt the metal and scrub it out with a steel brush.

Did I forget to mention, these three coaches are from a batch that came out of Derby Litchurch Lane in 1972 without any brake gear whatsoever?

 

[mickoo]

For the stubborn whitemetal clagging up a file, run it in a flame for a bit to melt the metal and scrub it out with a steel brush.

Did I forget to mention, these three coaches are from a batch that came out of Derby Litchurch Lane in 1972 without any brake gear whatsoever?

I hammer a piece of 20 mm copper tube flat and then push/scrape the copper along the grooves in the file, in your case of the image above from top left to bottom right, after a short while the copper becomes grooved to match the file and easily picks out the white metal lumps. Was taught that at basic tool college 30 years ago LOL.

A blow torch would also work quite well....runs to make note to purchase said item and obviate cut hands from holding flattened copper tube in future!

 

[lnerjp]

Dust the file with talcum powder first helps to prevent them from clogging up.

J.P.

 

[mickoo]

Dust the file with talcum powder first helps to prevent them from clogging up.

J.P.

LOL, try doing that in front of 30 hormonal driven youths in a workshop, seriously, one old tutor used to use French chalk, I suppose that's much the same technique?

 

[Bob Reid]

Only yesterday I asked Bob about the size of the visible portion of that strip on the Mk.1 carriages... I wonder if Bob's answer is applicable to Mk.2 carriages? (see the Mk.1 Resources thread)........
regards, Graham

Yes Graham, the (visible) dimensions in this reply - i.e. width & thickness of the anti-corrosion mouldings were the same for Mk1s or Mk2s (and if I'm not mistaken for the Mk IIIs as well though I can't confirm that).

Bob

(apologies Heather for interrupting your topic....)

 

[Heather Kay]

Apologies for the brief hiatus. After a couple of days of filing whitemetal bits, I needed a short break at the local care home for the bewildered. It must be lead poisoning.

Hopefully, very soon, I shall be able to explain my whitemetal soldering techniques. Watch this space, as they say.

 

[Heather Kay]

Soldering whitemetal

(I haven't illustrated this text. Try as I might, I don't have enough hands to operate the camera as well as the tools. I might consider a video at some stage.)

Many still consider soldering a black art. It really isn't. You just need the right tools and some knowledge. I would suggest soldering whitemetal is easier than soldering brass or nickel.

I cut my teeth soldering Langley Miniatures lorry kits together. My first Langley kit had been superglued together. I still have it, some quarter century later, but the glue has become brittle. Bits are beginning to drop off the model. I suppose I could have used epoxy, but I’m an impatient modeller, and dislike waiting for adhesives to set. Soldered models, only slightly younger than that first lorry, are rock solid.

So, what are the “secrets”, if any? First, let’s consider the tools.

• A temperature-controlled iron. It’s important not to let the whitemetal casting suck the heat from the tip, so an iron that will maintain its tip temperature is vital. I currently use a cheap import digital 48W “sodering station” [sic] from Maplin. It probably cost about £20. I took the precaution of acquiring a set of matching replacement tips, because experience tells me the cheap imports are not often compatible with the next cheap import the company sells once the container load has gone.
• Tools. Old needle files - not your best files - and a variety of scrapers and blades for cleaning up the components, before and after soldering. I have numerous offcuts of softwood to act as supports and protection against excess heat. You may also use pliers, tweezers, blutack, clamps, whatever, to hold components while you work.
• Flux, which prevents a cleaned surface oxidising too quickly, and lets the solder “flow”. You can buy all kinds of special concoctions for specific types of soldering, but I have to say I have used Carrs Red Label for years on both brass, nickel and whitemetal with no problems. As our American cousins might say, your mileage may vary. If you don’t use flux, the solder won’t “take” to the mating surface, and a poor joint will be the result.
• Solder of the right temperature range. My preference is for Langley’s home-brew type they sell on their stand and web site, which is short sticks, about 60mm long, and which melt at around 150°C. I’ve also used the Carrs brand 145° stuff. It’s all the same, really, just a kind of whitemetal alloy that melts at a lower temperature than the stuff they use for castings.

The technique is simple. It takes longer to describe than to do.

• Clean the joint faces with a file or scraper.
• Apply the flux with a disreputable brush.
• Pick up a blob of solder on the iron and “tin” each cleaned area. It only needs to be a thin coating, but it needs to cover the area to be joined. For hidden joints, I also tin down sides and edges to aid the heat flow into the mated surfaces.
• Bring both parts together, and make sure they won’t move during the process.
• Apply a splash more flux to the joint, pick up another blob of solder on the iron’s tip, and apply the heat.
• Let the solder flow, which sometimes takes a couple of seconds while the heat is transferred. You can see the melted solder draw along the joint. Sometimes, you can draw it along by moving the iron along the joint, like a paintbrush. Some would see this as heresy, but it’s sometimes the only way to apply heat over a larger area. Equally, it’s heretical to bring the solder to the work on the tip of the iron, but it’s not possible to bring iron and solder together as you would when soldering electronics or brass.
• Wait for the flux to boil off (avoiding the fumes if at all possible), withdraw the iron and hold everything until the solder turns from shiny silver to dull silver.
• Test to ensure the joint is firm, and clean up as required. Unlike glue, you can reapply the iron to melt the solder and adjust if something isn’t quite true.
• Don’t forget to wipe the iron tip on a damp sponge regularly.

Oh, I forgot the bit about the temperature of the iron! While the solder may melt at 150°C, the iron needs to be a fair deal hotter to get heat into the piece. The casting alloy can vary from kit maker to kit maker, so if this is the first time soldering a kit you may need to test on an inconspicuous part to ensure the iron won’t melt the component! For the JLTRT bogie construction, a temperature of between 180° and 190° seems about right. Enough to melt the solder, push heat into the castings but not cause any damage.

Looking after the iron’s tip is important. Using a resin-cored solder, for brass or electrical soldering, the advice is to leave the solder on the tip between use, cleaning it off before bringing it to the work. For whitemetal soldering, it is best to wipe the solder from the tip after making the joint. Never use abrasives or files on the tip of the iron to clean it.

Remember that whitemetal castings can act as excellent heat sinks. A large casting will suck the heat from the iron’s tip, and it might take a while for the solder to melt and begin to flow. It might also take a while for the heat to dissipate, so be careful picking things up after making the joint! Picking up a small blob of solder and adding it to the joint as you make it helps, because sometimes you need to form a fillet along the joint for strength. You can always clean up excess solder, so it doesn’t hurt to use more than you think in order to make a good joint.

You’re supposed to wash away flux residues after you’ve finished. I freely admit I don’t do this. Perhaps I’ve been lucky, but I’ve never had problems painting over a cleaned up solder joint. It could be I ensure the flux has boiled away completely, leaving no real residue to worry about. Do whatever you prefer, I make no warranties or guarantees!

One final thing, whitemetal soldering can also be used to fill and repair castings. The same techniques apply: clean the mating surfaces, flux, solder and heat. As the solder cools it contracts slightly, so you may need to add more until the filled hole is proud of the surrounding surface. Sand and file to finish. I used this technique on a set of axlebox castings a while ago. The holes cast for the Slater’s bearing cups were horribly off centre, so I filled them with solder, and redrilled them in the right place.

I hope that was helpful. As I said, there's no secret to soldering whitemetal kits. All you need are the right tools, the understanding of what you're trying to do and its limitations, and the guts to have a go and know you're not going to actually melt the whitemetal!

 

[Eastsidepilot]

You've covered the issue of white metal soldering completely Heather and I can't add anything.
The only thing I can say that may be of interest to others who are taking first steps with white metal is that the type of soldering iron that I have had success with,( and never melted a casting), is the adjustable temp. Antex 50watt used on it's lowest setting

ATB, Col.