Harlequin

Hi Brian, Are there any practical guidelines about good values for theta, t and the resulting length of the curve segment? I guess for most situations 0 < theta <= 90deg? The resulting spiral segment must have a minimum length to have a useful effect - maybe a multiple of the longest vehicle length? Do you know which track planning software supports transition curves and how easy it is to transfer them accurately to the real world layout? In your drawing: The Euler spiral segment should have 0 curvature where it touches the straight line but it appears to be curving immediately so it does not look convincing as a transition curve, I'm afraid. I think R' is potentially confusing. It's an arbitrary curve that you have drawn for illustration purposes but is nothing to do with the Euler Spiral segment. I don't understand how the two q distances can always be equal, as your drawing implies. For example if theta was large but t was small wouldn't the q distances be different?

I fitted the stiffeners today which make the side pieces into L beams for longitudinal strength and provide some racking resistance to hold the entire unit square. One of the ends had the PSE fixed wrongly inside the plywood. The stiffener stood proud so I had to chisel out a little rebate: The frame was remarkably square (1609mm across one diagonal, 1610 across the other) so I just glued, screwed and pinned the stiffeners into place without making any other adjustments: The stiffeners really work - the unit is very rigid in most directions now but it flexes a bit more than I'd like when one corner is lifted. I still need to connect the spines to the ends but I think some sort of diagonal bracing will probably be needed. Turned the right way up with the stiffeners at the bottom:

I was really taken by three new images of Llanglydwen station posted on disused-stations.org.uk recently: http://www.disused-stations.org.uk/l/llanglydwen/index.shtml It is thought that they were taken between 1923 and 1926 and are full of atmosphere, showing a wealth of detail packed into a small space. The photos were taken from the other side of the valley and so the shots have some distance and take in almost the whole station from slightly elevated viewpoints - just like photos of a model. This tiny station and it's immediate surroundings have many "modelable" features: Level crossing Station building Two platforms Passing loop Goods siding Signal box River in foreground Stone bridge Huge tree overhanging road Quirky buildings in background Pen-y-bont Inn in the background Natural amphitheatre setting with rural countryside backdrop It occurred to me that this wonderfully compact little scene could possibly be modelled accurately to scale without having to compress anything. So I have traced the maps and tried to reconcile old info with newer map info and with the photos. This is what I have got so far: Llanglydwen 6.pdf It is just under 4 metres across at 4mm scale and would have to be very deep to capture both the Inn and the bridge over the river. So, it seems that a feasible model would have to be compressed after all, which is a shame. Since I'm already deeply into the planning for a different layout entirely, I'm not sure what to do with this now! Maybe inspiration will strike me if I leave it alone for a while. Maybe someone here on RMWeb will have an interesting idea...

I made some more progress on my open frame baseboards today. I glued and screwed the side pieces to the ends to create a flimsy frame. I drilled out some holes in the rib and spine pieces. The exact position of these holes isn't really important but for neatness I clamped the ribs together and drilled through all 5 at once. Then I glued the ribs and spines into their grid pattern. Some of the fits were a bit loose so I had to weigh everything down while the glue dried. When the grid was set, I fitted into the frame and glued and pinned it in place. Some of the pins were too close to the edges of the ribs and they split but it's not a problem because the edge stiffeners will be glued over the splits The two spines don't meet the ends, as expected because I had to plane the PSE pieces down to remove the bowing in them. It just means that I'll have to fix some blocks to join them to the ends. I'm not worrying about squareness yet. I'll get the unit exactly square when I fix the edge stiffeners and corner braces. However I am worried that it might not be strong enough - the acid test will be for me to sit on it while it's only supported at the ends...

I'll just repeat that the loco was supplied with the stripped screwhead in my case. So if the wrong bit is being used it's at the factory but I suspect it's more a case of overzealous use of a power tool during assembly. BTW: I'm still waiting for Locomotion to replace my Dean Goods. They picked up the original but haven't told me exactly what they are going to do about it yet. So I'm currently out of pocket and getting slightly anxious...

A trick that others have used (e.g. Iain Rice) is to mount the layout at about chest height. That gives you room below for desks and other furniture and puts your eyeline at a more realistic angle to view the layout - as if you were standing on a nearby hillside rather than flying a helicopter!. Obviously that has Pros and Cons but it's something to think about...

I'm sure it's possible to tweak things to have decent length platforms (say, 5 coaches) within your room size, even while using medium radius points. (BTW: If the room is actually 4.5m long then it might be worth thinking about why you want to only use 3m of it because the extra length would be really useful!) As David says, you can start some of the pointwork on the curves and you don't have to do it literally 90 degrees around the corner. Use the curves to throw some lines out "centripetally", as it were, just outside the station. Use the Peco curved points to pull passing loops and sidings in from the main tracks. (The curved points are also great for forming crossovers on the curves.) You could align the station somewhat diagonally to squeeze a bit more length and perhaps even combine that with curved platforms, which always look great, for yet more length. Have the curves at one end of the station generous for a nice sweeping entry or exit and at the other end hide or obscure the tracks and use a tighter radius to get a bit more room. And don't forget to leave enough width for platforms and the station buildings behind, even if they are low-relief.

Thanks Steve! I justified buying the table saw combi machine on the basis that I've got lots of joinery still to do in the house. It was a bit of a luxury (and it took a huge effort to get it up the the shed) but I think it is proving it's worth. (Especially on railway things!) The mitre saw was another difficult-to-justify purchase at the time but, oh boy, does it make life easier! Cutting is so much faster and more accurate than doing it by hand. My Grandad was a carpenter and when I'm working in the shed I often wonder what he'd make of the fantastic tools available to us today.

This afternoon I worked on using the parts to put together one baseboard. Cut the parts to exact length in the mitre saw. This ensures that the parts are exactly square and gets rid of any rough corners. Cut the PSE that strengthens the ends of the frame. It's not the best quality and although it was reasonably straight and not twisted it was badly bowed so I ran the pieces through the planer just to square things up a bit without changing the dimensions too much. Glued the PSE to the end frame ply. I might add some screws later. Cut half depth slots in the spine and rib pieces using the depth stop in the mitre saw. Did a dry run on the workbench: So far so good. No major disasters, yet...

I realised I needed to make a roundy-round test track so before I get into making the complex baseboards for Hampton Malstead I have decided to make some simpler baseboards for the test track using the same basic techniques. Here's the plan for one of three identical boards which I will arrange in a U shape with a thin bridging piece across the top of the U to allow a continuous circuit of track to run around. Open baseboard.pdf I brought a sheet of 9mm ply up to the workshop during the week and ripped it into 6 smaller pieces: Long for the sides, spines and stiffeners, medium for the ends and ribs and the remaining short bits for corner braces This morning I sliced them into 78mm and 69mm strips. It was hard to get straight edges on the 1440mm long pieces even in the table saw because the fence wasn't long enough and the sliding table only slides 1200mm. (Note to self: Maybe design basebords that are only 1200mm long next time.) I Googled the problem and the simplest solution was to clamp a long straight edge to the table to form a longer fence. I used my 6ft level and some tricky adjustment was needed to get the fence set at the right offset. I think it improved things a bit but the edges were still not as straight as I'd like. So, I now have a stack of ply parts to make two baseboards, plus some extras so that I can select the best ones Meanwhile, outside:

How about this: It's the same topology as your design (which is actually a very common pattern) but hopefully a bit more flowing. I assume the curve off the board to the right leads to a fiddle yard of some sort??? I hope so! P.S. Some people might say the the spur above the quay will be really difficult to shunt. They're right but you can argue that that's a good thing because it makes operations more challenging and keeps the locos working on scene a bit more. Edit: P.P.S. There is room for a tank engine, such as a small prairie or shorter, to run round two coaches standing at the platform. Something like a B-set or a pair of clerestory coaches.

With solenoids, the point blades snap from one side to the other with a loud BZZZZT-CLACK. With DCC servos, like Cobalt, the point blades slide gently across from one side to the other with a small whirr. DCC control software running on a computer, phone or tablet can present the point controls in any way it likes - and thus any way that you the user prefer to see them. Raw DCC address numbers, switches on a control panel, or maybe a 3D-modelled full size lever frame in your own 3D signal box (with clock ticking and fire sizzling in the stove behind you). I know what you mean about the satisfaction of using physical controls, though.

Investing in a compound mitre saw will pay you back over and over again in terms of speed of working and accuracy of cuts.

Here are my plans for an open frame baseboard module that I am proposing to construct for a test track before I do something more complex for a proper layout. So, be warned: I haven't actually built this yet! So it's all a bit theoretical and I don't know for sure if it will be stiff enough - but it looks OK, I think. (If I didn't have to work for a living I'd be out in my shed, knocking this up today!) More details, drawn to scale with a cutting plan are in this PDF: Open baseboard.pdf

That is correct assuming that the point is an electrofrog point. If the point is the new Unifrog type then you will need to connect one of the outputs from the motor to the wire that drops down from the frog. But nothing too scary!

It's beautiful. Just the right amount of grime and lichens on the roof tiles. (And UV varnish answers one of my questions about self-printed papers, thanks.) With the two tall, unconnected walls, is it flimsy? If so, does that worry you or do you just have to be careful with it when it's off the layout?

I assume you mean #201. I don't understand why the 2ft radius curve would be disruptive and, as covered above, the incline behind the Ledbury backscene is reasonably accessible from the access hatch and from behind. Other hidden trackwork is accessible from the side and from above by the suggested lift off sections of scenery (green dashed lines in the drawing). I would argue that accessibility is not much worse than in #72, which also needs side access and lift-off access to the fiddle yard feed triangle. (And consider the difficulty of fixing broken droppers or bad joints on the branch line bridge behind Ledbury viaduct in #72.)

Hi Philou, Re. plan #201: The tight radius of the Gloucester branch on leaving Ledbury is a compromise to make the design work and is comparable to the relatively tight curvature of the prototype (in compressed model form). It could be wider but that has knock-on effects. In mitigation; it's a branch line, the curve occurs where the line disappears out of view so will be somewhat disguised and in compensation note that the radii on the visible main line are much larger than 1.0m. Where the branch passes behind Ledbury station it is simple straight line, so should be reasonably trouble-free. Note that the access hatch allows you to reach a good distance along the line to poke recalcitrant trains into life and the 6ft drop behind is actually a good thing because a ladder would allow further access from the ground floor if required. (BTW: The false backscene is just the most obvious way to hide the branch line behind Ledbury but there are other options.) Since Ledbury and Pontrilas in the real world are not directly connected and on completely different lines with Hereford in between, the fact that they are connected in the "wrong" orientation in the model shouldn't really be a problem. Modeller's license is already being applied to allow them to be directly connected at all so a little bit more, and judicious use of the turntable, should be enough to handle the orientation issue.

In #201 I don't think any features need to be lost. I placed Philou's original stations at the correct scale underneath the two station locations to ensure that the necessary length and width was available. You can see that I roughly aligned the platforms and that other details would fit by altering their alignment. They may need some tweaking but nothing that would prevent the design from working. As we have covered earlier in the thread, a train leaving Ledbury would pass through Pontrilas in it's guise as some other station on the network and vice versa. And the turntable fiddle yard would allow a westbound train from Ledbury to enter Pontrilas from the north east (i.e. also heading south-westbound) if required like this: Leave Ledbury heading west Pass through <not Pontrilas> Enter the turntable Turn the table so that the train is facing Pontrilas Exit the turntable Enter Pontrilas proper from the north east end. The branchline from Ledbury to Gloucester does indeed have a tight (2ft) radius but that is conservative by many standards, shouldn't be difficult for branch line traffic and is designed to start ascending only when it hits the straight behind the false backscene. (The design in #201 really needs to be drawn fully including complete stations and levels to be absolutely certain this all works as intended.) P.S. If Denbridge or anyone else could elaborate on the other potential problems in #201 that have not be addressed in the last few posts, I'd be grateful of the opportunity to answer them and/or to understand where my design fails (and hopefully fix it).

I omitted to mention that this compact area also contains: the signal box, which is just at the end of the short platform, a goods siding and the Pen-y-bont Inn just behind the level crossing. This beautiful little place was made to be modelled.