Miss Prism

Excellent circuit, Beeman. I had been planning something similar for a sector plate, with 'slowdown/speedup sections' being optically detected/activated rather than your mechanical 20mm targets, and the 'final position' detector also being a collimated opto. I do have a couple of those interruptors somewhere (from an old printer), but it never occurred to me that they could have that kind of accuracy (0.5mm). Presumably, your limiting final position accuracy is given by the diameter of your paperclip wire targets? Btw, a couple of minor queries on the circuit:

The prototype location for that bridge is bugging me!!!! Bath?

I do like the finish of 80265.

Aw, I dunno, that might be what quite a lot of people would like! Roll on that Toplight suburban set in crimson lake...

Excellent colouring on the backdrop; did you tone it down, or just leave it up to your phone camera?

Airfix did have the most lurid set of colours for their wagons didn't they?

Nice, but I'd like to see a workbench thread on how you put the those neat window frames together.

Bit difficult to comment without the plan being more to scale (how much length is there between the loop entry and the goods yard entry turnouts?) and in the absence of knowing what moves you want to cater for, but I can't see much of a function for #3 at the moment. Presumably your goods trains will always enter the platform road?

Ah yes. Hadn't spotted the brake difference. I have seen some Cambrian mermaids made up, and being one of their later kits, they can be made to look very good. (And cheaper overall, even with Bill's units underneath, than the Flangeway RTR.) The lack of open framing on the RTR isn't too visible unless at short range. I'm trying to set up some topless Bill units in a Parkside hopper at the moment to preserve the open frame look - this is proving to be a bit tricky! Btw, the clickable url for the Mermaid underframe only shot is: http://gallery6801.f...t/p9709401.html

The tipping chains on the model are oval, rather than round, as I think all the prototypes were. The link lengths are very overscale. The brake lever isn't joggled in, so the brake ratchet and guard are too proud of the solebar. There's plenty of room between the W-irons for P4/EM wheelsets. The brakes are aligned for 00 wheels, understandably, but can be bent outwards to suit the wider gauges. The W-irons aren't Mermaid typical, but do look reasonably like the originals fitted to some, as can be seen on Paul Bartlett's page. Nice looking wagon.

Lose the sides. Or better still make them detachable. (I'm thinking of lighting when you take pics.)

Missy - you might find this useful on the power supply: http://wiki.ehow.com/Convert-a-Computer-ATX-Power-Supply-to-a-Lab-Power-Supply (I think there are a couple of youtube 'howto's as well.)

For that thickness of recalcitrant MDF, I'm not convinced any 2" batten will be strong enough to counter the warping.

Is it possible to dissassemble the thing, and then reassemble with the two convex components facing each other?

What's the body width of the Hornby Hawksworth tender?

CoT has the later de Glehn bogie. I don't think any of the Singles got fitted with those, or if they did, it was only in their last days, when they looked a lot different to the Triang body moulding.

Yes indeed. Very post-modern!

Here's Tenby, with the small hut at the far end of the up platform being what I call "the token hut". Waits at Tenby can be up to 10 minutes as trains cross. Sorry, OP, we're waay off topic now...

I love these peek-a-boo cameos. Strictly speaking, cart roads should be wide enough for them to turn, but I think we can pretend Mikkel's is a one-way arrangement! I think my major comment is about the big aperture in the rear wall of the depot. Also, the far road seemed to me to need a bit more of an excuse for its existence. Anyway, in a effort to "busy the scene up", here's a scribble.

Yes, there's the rub, Mike. It's an interesting stock pattern though, with the Fishguard trains (2 up, 2 down, per day) being 3-car units (rather sparsely occupied), the Milford trains being 2-car (150s primarily), the Virgin Camarthen semi-fast trains being 2-car (usually very well populated out of Swansea High Street, and often choc a block), and typically a single car 153 (also often packed) for the all stations Pembroke Dock service. I have seen 150s on the Pembroke train occasionally, but the usual picture at Swansea High Street on all the westbounds is quite a scrum as passengers try to get a seat.

I'm not familiar with the magnitude of the Tortoise operating arm force, but ideally, there needs to be two areas of decoupling: first, between driver and operating arm; and second, between operating arm and the blades. The latter (just sufficient to keep the relevant switchblade snug against the stock rail) should be a lot 'gentler' than the former. The distance between the upper end of your tube upstands and the blade fixing will be significant, as will the fit of your 0.28 wire within the tube internal diameter.

Well thought out. I like the adjustability of the upstand tubes. Personally, I decouple the operating arm and the driving motor with an omega- or z-loop, but maybe you won't need this with the Tortoise.

Penhros - many thanks for the U25, T49 and T32 drawings. Very nice! Apropos the coach at Didcot (it must have been hiding until recently under one of their tarpaulins in the coach sheds), assuming it really is 416, then yes that would make it a T49 according to Harris. However, Harris denotes T49 as an 8'6" wide body, which would make it City stock, and not what Buffalo was after in the OP. And if T49 is City stock, why hasn't Didcot's example got the Holden doors? So is Harris wrong*? Is this a 8' body or an 8'6" body? I'll start that second para again - having looked at my primary copy of Harris (I have two, no, don't ask), I have done a pencil amendment at some time in the past to denote lot 700 as 8' wide, rather than 8'6" as given in the list. Didcot's specimen is definitely 8' wide, because the 8'6" wide City stock didn't have duckets. Looking at some old correspondence with John Lewis, he confirms that figure 59 of GW Coaches Part One is a T49, and that lot 582 (which includes Didcot's example) is T49. * there are some typos in his list

Ultrascale has a suitable wheel. (Edit: subject to knowing Bachmann's driving axle size of course, which is probably 3mm, so the Ultrascales as they are at present will require rebushing, or the Bachmann blocks will need to be rebored.)

You'd have to refit the old slide valves and boiler to find that out...