Paul's workbench

[kimballthurlow]

Dumbarton seems rather current ... for some reason.

Kimball

[Atlantic 3279]

Stac Polly / Pollaidh, Muckle Flugga?

[Danby Wiske]

Wow.... that's Brutal.....

In my defence, the joke was told to me by an Australian!

[nzpaul]

Stac Polly / Pollaidh, Muckle Flugga?

Exotic, difficult to spell/pronounce Scottish place names....could be even better than sheep breeds.

Wow.... that's Brutal.....

In my defence, the joke was told to me by an Australian!

Hehe, all good. I'm surprised that the "west island" gag hasn't been seized upon...usually invokes some witty comebacks.

There's a severely chopped up A1 body sitting on the table at the moment. Going to need that name soon I think.

[nzpaul]

Hi All
Rough assembly of my imaginary high tractive effort Pacific. The chassis is one of the really old Triang types that's screwed together, perfect for this application. Boiler has been shortened and splashers removed from the running plate. The wheels are an old set of 24mm Romfords that will need the flanges shaved a bit to stop them interfering with each other.Cylinder position sorted out and it all sits at the right height. Concept proven so I guess I'd better finish it. I'm thinking about making a P1 type tender but on a standard wheelbase 6 wheel chassis, trying to make it stand out for other reasons than just being a shorty A3.

As expected its dimensions are very close to that of a V2.

Cheers
Paul

[Hatfield Shed]

... I'm thinking about making a P1 type tender but on a standard wheelbase 6 wheel chassis, trying to make it stand out for other reasons than just being a shorty A3...

Alternatively, you might think about improved route availability, the more compact loco is a move in this direction. What would help on the tender is a twin bogie arrangement for greater track kindliness on tighter curves. This was sketched out at Doncaster so not wholly alien. (You need the tender capacity four axles offer. V2s were hampered by the water capacity limitation of the three axle tender.)

[NZRedBaron]

True enough; I have a slightly battered copy of Brian Haresnape's pictorial history of Gresley designs; on page 16 of which are two developmental draft schemes (dated May 1934 and March 1935 respectively) for the A4 class; the 1935 draft design has a streamlined corridor tender with a capacity for 9 tons of coal and 5000 gallons of water, mounted on a pair of two-axle bogies.

[nzpaul]

Alternatively, you might think about improved route availability, the more compact loco is a move in this direction. What would help on the tender is a twin bogie arrangement for greater track kindliness on tighter curves. This was sketched out at Doncaster so not wholly alien. (You need the tender capacity four axles offer. V2s were hampered by the water capacity limitation of the three axle tender.)

That's an interesting idea, a bogie tender isn't something I had considered. I've cut up some more bits of paper to make mock ups of ideas currently on the table, the P1 4700 gallon tender and a GNR 8 wheel with a pair of bogies from a Lord Nelson in place of the rigid 4 axle chassis. The SR bogies look similar to the type under the rear end of those weird articulated NER Atlantics that were fitted with booster engines. I'm not sure which I like best. It may come down to cheapest availability of parts, a 6 wheel tender can be built with parts I have already, not sure where I'd find bogies that look like these.

What do you think?

Route availability would be the same as A3 I would imagine. Surely it would end up very close in weight to a V2 or A3, somewhere in the 90-100 ton range for loco only, with a 4 wheel front bogie it might be heavier than a V2, maybe not. It wouldn't be a light weight though, especially if the idea is maximised tractive effort.

Paul

[nzpaul]

Hi All
I'm continuing to muck about with the chassis for the 6'2" Pacific. I've built up this Comet 50:1 gearbox and driven it with a Scalextric Red motor, these are normally for hotting up an F1 slot cars, but I bought a few cheap and thought it worth a try. The motor is rated at 20,000 RPM no load and supposedly has more torque than the standard Scalextric motor, that's significantly more revs that the FF050-11170 motors I've used for a couple of other models with the same gearbox. Running on the rollers it behaves quite well and even chugs along at slow speed happily enough. The motor does turn over at very low voltages so once a DCC chip is fitted I think some form of electronic governing may be in order, a theoretical 400RPM at the wheels would be quite extreme.
The coupling rods are made up from a set of Gibson "Universal Rods" which despite my best efforts at accuracy still required some adjustment to achieve smooth running. I won the battle in the end after about an hour and a half of filing and testing.
I Might have to do something about the Red colour as well, it's visible with the lid on.

Quick video of it running.
https://www.youtube.com/watch?v=CiMQJGK4U7c

Cheers
Paul

[Hatfield Shed]

...Route availability would be the same as A3 I would imagine. Surely it would end up very close in weight to a V2 or A3, somewhere in the 90-100 ton range for loco only, with a 4 wheel front bogie it might be heavier than a V2, maybe not. It wouldn't be a light weight though, especially if the idea is maximised tractive effort...

This depends on a package of factors in addition to weight; and of course the brief to the design team. The shorter frame and engine wheelbase compared to the A3 pacific is a move in the right direction for all of weight reduction, minimum negotiable radius and a more compact dimensional envelope to fit within the loading gauge. Some of Mr Bulleid's funky ideas on frame design and wheels, might be handy.

[nzpaul]

I suppose when you're building a theoretical model, its purpose and specifications are entirely up to yourself. My own ideas if it being built for high tractive effort with no concessions to route availability, or the alternative idea of a "light pacific" are equally viable. With a bit of modellers licence you could argue the case of this as an alternative to the B17s or something like that.

Paul

[nzpaul]

Hi All
I mentioned my C12 in another thread the other day, it's a model I've been meaning to revisit for a while. I'd originally called it finished in 1997, 24 years later it's time to have another look. The first job was to re-power as the original Sagami open frame 5 pole motor will require major surgery to become DCC friendly. I've installed one of the Hornby Type 7/Romford 50:1 gears combinations I've use in other small engines. I've also tidied up the brakes while the chassis was in bits, reminded me why it was a good beginners kit, the chassis is a fold up etch so no need for jigs etc.
I had to scratch away the paint around the top of the tanks and cab to solder on some beading and use insulation tape to add some boiler bands which I had omitted first time around. Also made repairs to the bunker coal rails and fitted lamp irons front and rear. I suppose I should sort out a boiler backhead and cab interior as well. Back to the paint shop soon to refinish, then figure out what to do with it. This was built years before I took an interest in DCC or started concentrating on things associated with the Waverley Route so a C12 is going to be something of a rule 1 interloper.

Paul

[nzpaul]

Small update on the imaginary A2.1.
I thought I might share how I've set up the pick-ups and brakes. Although it's unavoidable in many cases, I don't like metal brakes in close proximity to the wheels as it's all too easy to create a short circuit inadvertently. For this model, I've soldered the brake mounts to the pick-up PCB with no cross rods linking the two sides, if something occurs that causes the brake shoes to touch the wheels they'll act like another pick-up, not a particularly accurate representation but certainly practical.

Valve gear is made up from spare Hornby A3 parts and only required the shortening of the connecting rods and the radius rods, fiddly but not too stressful. The elongated Hornby expansion links are exacerbated by the shorter wheels giving the gear a slightly awkward gait when in motion. To attach the Hornby return crank to the Romford crank pin I soldered a crank pin spacer washer to the return crank with 60/40 solder then 100deg solder to the crank pin in the hope the high temp stuff would hold together (it worked).
I've re-deployed a pair of Bachmann V2 rear frames for the trailing wheels again, unlike "Captian Cuttle" a couple of pages back, this chassis didn't allow for them to be set up as a removable unit so they're supported on a simple plastic box under the cab.

Paul

[nzpaul]

Hi All
I've decided to stick with my original idea of a P1 style tender for the fake A2 and after around 6 hours I have this to show for it. Once this one is completed I really need to go back to my old P1 tender and bring it up to this level. It probably would have been easier to find a GBL V2 tender or similar and modify, but this has been quite fun.

Also started on the conversion to left hand drive and fitting of some GK resin parts to make a nice looking boiler, awaiting header covers and handrails but I got distracted by the tender. The front bogie is an old Hornby tender drive FS type complete with slightly ugly wheels, they may get changed yet.

Paul

[nzpaul]

Hi All
One last photo before the weekend is over. It's occurred to me that we refer to A2s as being Raven, Thompson or Peppercorn, so based on that, this will officially become a Gresley A2 (in my head at least).
Hand rails and header covers now fitted, the hand rail knobs are some long weird looking things that I didn't want to use on anything else,I'm not sure where they came from but, waste not want not....perfect for this project.
I've run out of parts to go any further on the tender and have sent a fairly hefty order to Wizard Models for all kinds of bits and pieces to finish this, and a few other models.
Tender propped up on paint brushes to mock up the way it will look.

Cheers
Paul