Atlantic's works: Portable layout - Ground Signals Again

[S.A.C. Martin]

That's interesting Tim - does that cover all the A2/3s? If so, I may need to get the scalpel out on mine (60500).

Modifications looking good Graeme. Really enjoying the steady stream of updates.

[mick b]

I drilled the footplate for the Wolf for the wire with a 0.5mm drill it went through very easily

I use Staples bent to shape and glued under the footplate for lamp irons = nice and strong

Simon

Get cutting they never had the step on the Smokebox .


Good spot never noticed either

[S.A.C. Martin]

Thanks Mick, cutting in progress!

[Atlantic 3279]

Doh! That step!!! Just as well I've only tacked the door in with three little spots of Evostick.

I'd agree with Mick about staples for lamp irons, easy enough, strong, steel so take paint well, unlike brass at times. Maybe not as fine as etched lamp irons, but if you plan to plant drilled, plastcine/blu-tac filled lamps on them at times, robust may be better than dead-scale.

[Tim79]

Re: staples - I have a large box of #16 staples for that very use. The difficulty I have is working out how to do the blanks left by the absence of electric lighting, where the lamp iron is on top of a C shaped (in profile) backing piece, for want of a better description.

I fear it's going to be a scratchbuild, which adds more time to this A2/3's build cost......

Graeme: was Steady Aim one of those that had the split handrail above the numberplate when moved or did it retain the full length one initially? I ask as the only images I've ever seen of it have split handrails!

Cheers,

[Atlantic 3279]

I think you may be right about the handrail eventually being the split type Tim. It's a poor approach, I know, but for the moment I'll avoid more work and use of more new handrail knobs and just leave mine in one piece as it is still "generically" correct for an A2/3 in later life. In the highly unlikely event that I am barred from running it on my mate's proposed layout until the handrail details are correct, I'll alter it at that stage....

It's only a Thompson loco after all!

PS - I can't think of an easy way to address the problem of the de-electrified lamp irons, other than to turn a blind eye or avoid modelling the locos that definitely had them.

[S.A.C. Martin]

If I may - I've been working on this problem myself because 60136 Alcazar had the exact same problem, and to boot, an unusual handrail/smokebox numberplate position. I have taken to creating the electric lighting in CAD to eventually have them printed out in plastic. Whether or not it works will depend on the results of my print, coming in a week or so's time. If it helps anyone else out when they arrive (provided the prints work), I'd be happy to make them available to all who want them.

[davidwest]

Re: staples - I have a large box of #16 staples for that very use. The difficulty I have is working out how to do the blanks left by the absence of electric lighting, where the lamp iron is on top of a C shaped (in profile) backing piece, for want of a better description.

I fear it's going to be a scratchbuild, which adds more time to this A2/3's build cost......

Graeme: was Steady Aim one of those that had the split handrail above the numberplate when moved or did it retain the full length one initially? I ask as the only images I've ever seen of it have split handrails!

Cheers,

Tim; Split handrails, lowered lamp irons, and speedo's was a very late alteration post 61. Some of the class didn't recieve the mods.

[Atlantic 3279]

Yet more on that matter of A2/3, A2/2, A2/1 eccentric rod length:

I'll check more carefullu later on, but a quick measurement of the official photo of Airborne, in Yeadon, which is larger and clearer that the A2/1 picture I scaled-up from RCTS, initially suggests an eccentric rod length of 17.3mm for 4mil scale. (Edit 6-15pm, I've just measured again, plus I've done the same on a large true-broadside print in Yeadon of the freshly rebuilt Wolf of B, and the results strongly point to a 17mm scale length). This moves the goalposts in this debate a little way back towards my "practical" fitted rod length of 16 to 16.5mm, and away from the 18mm or more that Isinglass drawing, dodgy photos, and Comet V2 parts were tending to favour. This may also dilute the evidence that was beginning to suggest that my motion bracket might be too far back owing to the slide-bars being too long. I thought I had originally set the motion bracket position accurately by careful reference to points on the body as well as on the chassis, and it is desirable if at all possible to avoid having to replace or further alter the slidebars or their mountings. It may be possible now by use of only minor tweaks to accommodate a 17mm rod in future models, especially with the potential freedom to use the extra mil that Bachmann have sneaked into each half of the coupled wheelbase.......

[Atlantic 3279]

Hmmmmm, however, as this very close look at the valve gear on Steady Aim shows, an eccentric rod which has (by accident) actually turned out to be 16.5mm long rather than the planned 16mm, almost knocks on the rear end of the slidebars. The bars are pushed home fully into the cylinders, and the cylinders cannot go significantly further forward without beginning to foul the running plate step (or equally without perhaps starting to look wrongly positioned compared to either the rear edge of the smokebox or the coupled wheels. It would be troublesome/risky to try to reduce the throw/offset of the retun crank to ease the limit on rod length, so perhaps in order to leave room for building error it would be unwise to go for more than 16.5mm length, even if 17 or more seems to be the true target figure.

And here's how things look with the cab lining re-applied as more of a square and not so much of a horizontally elongated rectangle, plus full size numbers now applied too. The relationship to running plate and reversing rod cover heights is almost right, and I don't think anything better can be achieved, as I believe now that there are at least two small errors in shapes/dimensions. Firstly Bachmann's rod cover, even without my extension at its rear, wrongly runs slightly "uphill" towards the cab along its top edge (so that by comparison with its line the numbers are made to look too low), and secondly the lower edges of the cab windows are probably a touch too low (making the handrail, the lining and the numbers all appear relatively too high!)

[mick b]

Looks fine to me Graeme well done.

Looking at the photo you have posted of the A2/1 there is no more than a couple of inches between the two parts a scale 1mm or less.

I dont think I would worry to much about 0.5mm in 4mm = 1.5 scale inches !!! If it looks right your 99% there.

[davidwest]

Really looks the business!

[2002EarlMarischal]

Really superb job Graeme!

[Atlantic 3279]

Thanks gents. While the issue of valve gear dimensions simmers away quietly, I've got on with some actual progress towards a result in other respects today.

Firstly, relax. The threat to to the very fabric of time and space has been removed. I have deleted that incorrect step on the A2/3 smokebox door, and that doesn't merit yet another picture.

Secondly, action has resumed on the A1/1 front after eight days of ceasefire. I decided to deal with the problem of the curved edges of the sidesheets on the cab and tender. The ex-A3 cab of course starts out like this:

In the same way that I use heat, and confinement between tubular formers, to produce evenly curved plastic "boiler plates", roofs and so on, I reasoned that I should be able to use heat and a pair of flat formers to straighten these curved edges. But how? I didn't want to heat the whole cab and finish up with some sort of "melting art form"
I decided to have a go at adapting my adjustable power soldering iron to act as a set of miniature straighteners. Firstly I took out the bit, and formed a strip of 10 thou brass sheets around the cold iron:

To this I added a buldog type clip:

I then gripped the curved edge of the sidesheet between the layers of brass, and turned on the iron:

I was careful to keep the whole length of the curved strip grippped by the brass layers, with the edges of these parallel to the edge of the cab. As soon as the plastic gave enough in the heat to straighten, I pulled the cab out of the heated clamp.

[manna]

G'Day Gents

And as we wait with baited breath ! we ask ourselves all sorts of mundane questions of the universe, like what is a quark, and would I like it if I knew !! ................ Oh come on, are we going to see a melted blob of plastic.......or,... sorry got to go to the shop for some milk..drats

manna