Harlequin

The pickups in the trailing bogie are in the axle bearings.

Yep, not really needed for the SRM because of its multiple pickups and long wheelbase. You'd be really unlucky to completely lose power with these if your track is up to any decent standard. On the other hand, it's so easy to add to the SRM because there's loads of space right next to the decoder. So if you've got the parts and 5 minutes to spare, why not?

After another session of fiddling at speed step 2/128 with a linear speed curve, I do at least get chuffs that seem to be related to loco speed. Having set CV353 to a reasonable sync at speed step 2 I then speed up the loco and set CV354 to get good sync at the faster speed. But that then throws out the sync at low speed, etc., in an endless spiral of doom. Man, this is frustrating! At the moment I don't think it's actually possible to get a decent chuff sync across a range of speeds with this decoder.

I have a Doehler & Haass SD18A with a steam sound project and I'm trying to sync the chuff rate to the host loco but it has defeated me so far. The D&H manual says that CV353 sets the chuff rate at speed step 1 and then CV354 adjusts it for higher speeds but the decoder behaviour at speed step 1 is not consistent: If I start the loco from 0 and go up one step (1 of 128) it makes no chuff sounds at all, no matter how many wheel revolutions I wait. If I accelerate up to a higher speed and then come down to speed step 1, the coasting sound stops responding to loco speed and just runs at it's own independent rate. So it seems to be impossible to sync chuffs at speed step 1...? I'm trying to set CV353 first and then adjust CV354 because that is the strong suggested method from the descriptions of the two CVs and empirically trying any other It's possible that some other threshold setting in the decoder is preventing the chuff rate from responding to loco speed at low speed inputs but I can't immediately see what. It's also possible, I suppose, that by "Speed step 1" they mean 1/28 rather than 1/128...? That's not clear but worth a try. Does anyone have experience of these decoders and setting the chuff rate? Update: While writing this, I've realised that I should probably try setting VHigh to max and setting a linear speed response.

I'm not sure photos of the sites with their trees today will be much help in identifying the trees that would have been in the same locations 100 years ago. Within that period Dutch Elm disease drastically changed the landscape, of course. ("Elm Road" is a strong hint as to the trees found at that location.) In the fourth colour photo in the first post, the trees in question have tree guards around the bases of their trunks so we know those have been intentionally planted and could come from anywhere. Can you post some photos of the actual trees from the period in question (or similar)? Or point us to such photos in @phil_sutters link?

The bomb is en-route as I type, apparently.

https://youtube.com/clip/Ugkxg3fs3YcK4rJSvIFmkt8aS2F7x5f60G6g?si=VowAIZiRVH0_mf5s

The tender in the batch1 moguls had a big diecast block in them with a well to hold a 40*20mm speaker so I'm a bit surprised you think it needs extra weight. Is there a speaker in the tender? I hope so! If so, you could make sure the diaphragm is facing upwards and do the mesh coal load thing.

That looks very rational. If you're happy with 2/3rd scenic 1/3rd fiddle yard around the room then it makes a lot of sense because you can see everywhere, reach everywhere and easily change things by hand in the FY. It also means that you don't need automation right from the word go - you can run the layout manually at first and get automation working in stages.

Yes, I like both Moor Street and Cheltenham St James. Just pointing out that if the goal is some roundy-round running with some shunting a through station is in many ways a better fit. N gauge makes a return loop much easier to do space-wise than OO but it's just a bit awkward to fit into the scenic parts of a plan. However, if it's in the off-scene area then it's much easier.

On the face of it you'd think 8 thrusts per revolution would make for a smoother ride - although maybe not because it would mean thrusts were not equalised across the frame. I think the practical problem is that the valve timing events offset at 1/8ths would require twice as many return cranks and possibly some separate outside valve gear if rocker arms from the inside were too complicated to set up. Remember that on the GWR four cylinder locos the outside cylinder valves are worked by rocker arms from the inside so their timing is simply the inverse of one of the inside valves.

Four cylinder and two cylinder GWR locos have the same number of chuffs per revolution. Sound projects are often out of sync at first. They can't account for all the loco/gearing combinations they will be used with and in this case it may have been set up for the old batch 1 Moguls where the gear ratio was different. (Sometimes sound project designers simply don't understand the chuffs per revolution of the prototype.)

All GWR engines do it, at least all those with crosshead driven vaccuum pumps. It's a pressure relief valve and should "spit" rather than knock or tap. When it's very loud @The Stationmaster will tell you that it needs some attention. 😉 You can hear it on this video on various engines including 5322. Edit: There should be two "spits" per wheel revolution and your chuff sync is way out - far too may chuffs (and spits) per revolution.

If you want a roundy round then a through station is easier to accommodate than a terminus. It means there's much less need for a return loop, which is space-consuming and usually has to be non-scenic. A through station can still have terminal bays and a goods yard that has to be shunted in exactly the same way.

Exactly. The way to get a warm, dry, stable, energy efficient structure is to have the framing and the structural shell inside the insulation layer and a breather membrane outside of that. (Although I would avoid petrochemical-derived insulation as far as possible.)

I made a shed in my garden to my own design. I designed it to be easy to build, with internal surfaces that I could join things to, well sealed and well insulated. I bought the raw materials from a builder's merchant and put it all together myself apart from pouring the concrete pad and sealing the roof with fibreglass. It wasn't difficult and the result is a really sturdy little building. I then filled it with tools and a workbench rather than a railway... What a mistake! You could do the same, Graham, and all the tools you need to build the shed are the same ones you need to build a railway - so can be more easily justified! (Apart from the nail gun which is a great thing to play with use but only really needed for major building work.)

Building a loco or any engineering structure in CAD is very satisfying in itself and you learn how they were put together and how they worked in some depth. 3D resin printers are getting better and better all the time. Good ones don't break the bank and print much better detail than the methods employed by Shapeways (at the least methods offered for model railway prints). There's still the problem of painting and lining the models to overcome but technology will undoubtedly come along to do that at home too.

Good decision about the goods shed, IMHO. My suggestion would be to ignore the coal sidings and either handle coal in the yard on the goods shed side or pretend that coal is handled at the Malvern Road yard instead. You haven't got room to do them justice and making them kickback would change the station operations significantly. What does the rest of the layout look like? To service a station like this you'll need a capacious fiddle yard. Does the FY continue on straight or does the track turn 90° to reach it?

I got my sound fitted No. 97 "back from the menders" today. The accessories bag is definitely the one I had originally and the loco had the address I'd programmed into it so I extrapolate from that that it really is the same model that I returned due to her developing a "limp" when turning right. A quick run shows that I don't see the limp where the whole body sporadically lifted up when turning right but now the motion obviously has a stiff point in it. Every wheel rotation goes through a point where it slows down then speeds up again, whether turning or running on a straight. And the sound file follows. I'm a bit disappointed but I'll see if there's anything I can do to make it smoother over the next few days.

To quote Douglas Adams: The two philosophers gaped at him. “Bloody hell,” said Majikthise, “now that is what I call thinking. Here, Vroomfondel, why do we never think of things like that?” “Dunno,” said Vroomfondel in an awed whisper; “think our brains must be too highly trained, Majikthise.”

The flyover bridges of the design you found were a nice feature - something you can do in N when you've got plenty of space and something that allows trains to cross in more interesting ways. Shame to lose them. The station is called "Camps Junction" but the two junctions are both a long way away, splitting and rejoining the mainline for no obvious purpose because both branches follow basically the same route. The "branchline station" appears to be on the main line...? It seems a bit odd to have a double track main line passing immediately behind a major station, with no interaction between the two (but I bet that does happen somewhere in the real world). How do passengers get to your island platform with so many tracks either side? Edit: The dumbell format does restrict what you can do a bit and causes the potential reach issues. If you could run some of the tracks completely around the space with a duck-under, lifting section or gate to access the operating well, then I think a layout would flow better with more open curves, easier reach and a more comfortable operating space.

Some weight needs to be embodied in the model for decent pulling power. So perhaps the chassis is more suited to being CNC milled out of metal than 3D Printed. The shapes shown above don't look too complicated for a desktop milling machine.

Really? That's a new one on me! Who are "They" and do they own shares in cat shampoo? 😉 I've never washed any of mine and they've never been smelly but they have been known to jump into the pond by mistake. They made it pretty clear that it was not an experience they wanted to repeat in any form.

It's an MS450.

https://www.rapidonline.com/rapid-slotted-mass-set-with-hanger-brass-500g-52-0083 There's also a 1kg version: https://www.rapidonline.com/rapid-slotted-mass-set-with-hanger-brass-1000g-52-0082