PWM Shunter build

[auld_boot]

As promised here is a thread for the build of my Mercian models PWM shunter. Please don't expect rapid progress and frequent updates as I am by no means a fast worker.

The chassis so far looks like this:

As this is my first O gauge build I am keeping it simple with no springing/compensation/CSBs etc. Having said it was a simple approach this is the second attempt at the chassis, I first tried to build it using a few spare axles that I had to hand to keep things square.
After a visit to the gas stove with the first attempt I bought myself some foot long 3/16 stainless steel bars and used those to check for square. All axles now run smoothly and it sits square on a sheet of glass so fingers crossed.

Next up was the radiator casing and grill, I wasn't happy with the way the grill sat as designed. It meant that the slats were protruding out of the front of the casing, which looked odd to me. You can see what I mean if you look at the models here: http://www.modelrailways.tv/7mm-scale-diesels.html compared to the real thing here http://pwm651.blogspot.co.uk/2011_07_01_archive.html
So instead of front mounting the grill as suggested I used some fine L section to make a frame and rear mounted the grill etch. I'm much happier with the way it looks now.
I also closed off the square hole on the side and made a step for it from scrap etch.


Next the engine casing. Nothing much to say about this other than it's my first attempt at bending a part into shape (2nd if you count the radiator), this is where I started using the term 'fighting with the kit' as it took 3 attempts to get it to this shape. I've left the side panels off for now as I want to make it so that the body and cab is separate from the footplate and I think it might be easier to put the other body parts together before the side panels are on.


Footplate. The instructions say to solder the side valences into the half etched slots on the footplate. My footplate didn't have any half etched slots so I used some 2mm L section brass as I could think of no method that I was within my capability to get a 2mm strip of NS square to the inside edge of the footplate.


So with the startings of cab the loco parts so far when placed together look like this:


Which brings me up to date with the cab and it's lack of interior detail, with such large side and rear windows on these locos I cannot leave the interior without something resembling some workings. This is all I have so far, I have a feeling a trip to Aviemore could be happening soon:

 

[auld_boot]

As promised progress is slow, but it's gradually getting there. I've added brakes, some detail to the cab interior and the bonnet sides. Oh and inside I made half a dozen little L brackets so that the body can be screwed to the footplate.
I resisted the temptation to rearrange the bonnet side doors, for a while 97652 ran at Taunton with the centre doors at the front but I thought if I changed them I'd only have to explain it frequently and it would also restrict the model to being 97652 in yellow livery.



I need some advice please, I want to blacken the wheels. I know this is a much discussed subject and I've read all I can find on here about the process, clean, dry, warm, soak in dilution and then rinse and burnish. My problem is that my jar of Carrs metal black states it is for brass, will this work on the steel wheels?

 

[Jinty]

Nice progress on the diesel shunter.

For blackening steel, I use Birchwood Casey 'Perma Blue' found from your local gunsmiths. about £8 - £9 a bottle, it might be found on Ebay as well.
A good cleaning down with a piece of scotchcloth (Green pan scrubbers), then a clean with IPA, and then I use a cotton bud to apply the liquid out of the container, onto the steel tyres. Clean off with water. Re-apply if needed.

 

[Dikitriki]

I find you get a much better coverage with the blackening if you dilute it 20 to 1 plus with water. The reaction is slower and more controllable, and is less prone to wipe off, as sometimes happens with neat solution.

Richard

 

[oldravendale]

I too use Birchwood Casey Brass or Steel Blue and it usually works well. In the case of wheels I clean them up with a brass wire brush in a mini drill, then IPA before washing and applying a diluted 1:1 bluing solution. I've found the bluing solution a bit aggressive if used neat and, for me at least, by the time I've stopped the action it's started to flake off. I guess that, as with anything, you need to experiment to find a procedure to suit you. There are one or two primers on line if they help.

Has anyone used the paste or either of the pen applicators? They look mighty convenient - if they work!

Brian

 

[OzzyO]

Clean with meths and apply with a cotton bud, if your not going to paint them apply a light wipe over with a light oil. To clean the brass centre to the Slater's wheels I use a brass "pencil" brush in the Dremmel and follow as above.

OzzyO.

 

[Jinty]

I find you get a much better coverage with the blackening if you dilute it 20 to 1 plus with water. The reaction is slower and more controllable, and is less prone to wipe off, as sometimes happens with neat solution.

Richard

I'll certainly give that a whirl, as I blackened a pair of Slaters axles and wheels today for my upcoming BR brakevan, and it built up a bit too quick, and quite a bit ended up on the kitchen roll I was drying them with!!!!!

Clean with meths and apply with a cotton bud, if your not going to paint them apply a light wipe over with a light oil.
OzzyO.

Am I mistaken in assuming that the metal blackening slows down the process of rusting of the wheels?

 

[OzzyO]

Am I mistaken in assuming that the metal blackening slows down the process of rusting of the wheels?

You are not mistaken in assuming that the metal black slows down rusting. But I just find that a light coat of oil gives a nice sheen if it's not going to be painted as well. This is what I do on the backs of the wheels and axles.

OzzyO.

 

[simon.bolton]

I'd be interested to know whether anyone has had any experience of the blackening process acting as an insulating barrier to wheel pickup?

Cheers
Simon

 

[oldravendale]

I've used Birchwood Casey Metal Black on the wheels of everything over the last ten years or so and experienced no problems at all with pick up. All my stuff is DCC with the exception of a Sentinel which I've yet to get round to fitting a decoder in, but all run equally well.

Like OzzyO I coat any chemically blackened areas with a very light oil - I normally use Carrs Electrofix, but that's just because I've had a bottle for years and not spilled it all over the bench yet.

Brian

 

[The Penguin Of Doom]

I like the progress of the build so far, it's coming along nicely.

I might have missed it, but who manufactures the kit? The etches look nice and crisp.

Cheers.

Sean.

 

[Brian Daniels]

First line right at the top of the page says it's a Mercian Models kit http://www.modelrailways.tv/7mm-scale-diesels.html

 

[Brian Daniels]

Just wondering if this build got any further as I am building one at the moment and scratching my head with the lubricator.

 

[auld_boot]

Sorry Brian, very little progress on mine and certainly not got as far as the lubricator.
I've just taken a look at the parts that I think are meant to represent the lubricator (for some reason I have two of them?) and I can understand the issue you're having.
For one, there's nothing supplied with my kit for the mechanism that links it to the centre of the wheel. So it looks like some more fabrication is required, as there was with the cab interior.
There's quite a clear photo of a freshly painted lubricator setup here:
Strathspey Railway Aviemore PWM651
The same photostream has some cab interior shots as well.

Another issue I encountered was the air tanks supplied with the kit, they were way too short and fat to be correct. I've recently purchased some brass tube to make new tanks.

 

[auld_boot]

Just thought of a couple of other details I noticed, my kit has 4 identical sandboxes supplied but on the real thing the sandboxes under the cab are shorter than those at the front. Another thing missing that is quite noticeable on the loco is the little extension piece on the footplate beside the cab, I assume to allow the driver to walk to the front of the loco along the footplate (hence the horizontal hand rail on the cab side).

I'm not trying to knock the kit here, I realise there is a cost vs detail balance to met i.e. too much detail in the kit and it could price itself out of the market.

 

[Brian Daniels]

Thanks for getting back to us on this kit build, I don't think you are alone in having a kit that's taking a little while to do!

I guess you have not seen these pictures of PWM 651 now at the Swindon & Cricklade Railway on my Flickr site PWM 651 Details

Here are a couple of pictures of my build so far. I will put more pictures and my comments up on my workbench thread so as not to hog your thread.