Rabs

The thought had crossed my mind! I'd love to do the mixed gauge period as well. Unfortunately I just don't think that my personal interpretation of Rule 1 would allow me to run post-WWII liveries (which is most of my stock at the moment), on mixed gauge track. I'll save that for another layout I think.

The postman has just deliverd my copy of Colin Maggs' "The GWR Bristol to Bath Line". I wasn't sure how useful it would be when I ordered it but I'm glad I did. A decent proportion of the book is based around Bath, and the majority of the photos are useful in one way or another. A few highlights I might choose to incorporate: A GWR diver in classic bell-helmet climbing out of the river after inspecting the skew bridge piers below the waterline. Various experimental and one off locomotives at the station: Great Bear the trial streamlined Castle and King of the mid 30s La France the 4-4-2 Saint prototype (before conversion to 4-6-0) the GWR's first pannier tank (1490, a 4-4-0), which ended it's career as Bath's shunting loco A special excursion train from Fry's chocolate factory to London adorned with flags. Lots of useful pictures of prototypical train formations (particularly some difficult to find freight trains) A GWR livery scarab in front of the station building A whole host of beautiful outside frame locomotives All in all, I think that I'm going to have to allow myself some more flexibility on dates, I can't miss out on some of the gems that went through Bath in earlier times!

That's the plan. It's not quite perfectly the same height, but I'm happy that it's good enough. Once painted and weathered it should blend in nicely. In the meantime tracklaying has continued at a slow but steady pace: The traverser is coming together nicely. The first step was to mill a copperclad base which spans both the join between the module and the sliding join on the traverser module. Here it is rested in place: Next, a thin coat of epoxy on the underside and weighted down: I then laid the through tracks before making the two cuts. And here it is as it stands at the moment:

Cut a sheet of paper into a right angled triangle and cover with pritt stick. Put a round rod of the onto one edge and roll it up - instant taper. If you want a curved taper, cut the paper into an appropriate shape (for the shape of those lamp posts the hypotenuse of the 'triangle' needs to be concave)

I don't think that you should use a 15 ton steam roller in your loft - that would really upset Mrs C when it comes through the ceiling.

You're welcome. I'm not going to have time to build mine for a while as I'm tracklaying at the moment, so I'll look forward to seeing how yours goes.

I haven't removed the sleepers completely - just the 35micron thick layer of copper from the top surface of them. That was my conclusion too. It's a down train approaching Bath on the arches to the East of the station - I've got other photos from a similar angle with the same houses in the background. It has to be going towards Bath because that's where the slip coaches are due to stop. Judging from the angle I believe the train is about level with the cricket ground at this point. This suggests that the detachment occurred somewhere around the bridge over the Pulteney Road (A36). Nicely in my modelled area

I've just been working my way through the WTT for Bath. I can't find one for 1947, but I'm expecting the 1948 one written immediately after nationalisation to be pretty representative. It looks like Bath saw 81 trains a day in the Down direction on most weekdays. I've not gone through the Up timetable yet, but I assume that it will be a similar number. I think that I might need some more stock and some James Bond style revolving number plates for my locos! One interesting thing I hadn't appreciated before was that Bath was sometimes served by slip coaches off express trains running the Paddington to Bristol route. That should be fun to model! I'll need some on-board DCC uncouplers. Does anyone know how far up the line the uncoupling would usually be done for slip services? Also, the station speed limit at Bath was 30mph, so I imagine that the whole train would slow to this speed before uncoupling the slip carriages - I don't imagine that braking the leading train after detaching coaches would be a good idea! EDIT: I just found this website: http://mikes.railhistory.railfan.net/r134.html, which shows an action shot of a slip off the Bristol express at Bath - what a stroke of luck!. Judging by the livery this is c.1930 and from the buildings in the background I will be able to work out pretty accurately where the detachment has occured. So the only question remaining is what speed was the train doing when the slip happened, given that it has to go through the station at 30mph just a mile or so further up the track. Unless anyone can correct me I'm going to assume that it had already slowed to 30 before detaching the slip coaches.

A bit more fun on my lathe. These are some parts for the first of three wagon turntables I need around the station. The design is made more complicated by wanting to get an electromagnet within a few mm of the underside of the track, so I can't just run it on an axle. The ring component is turned from 1.2mm brass sheet and will be glued to the baseboard and. This thickness matches the sleepers of the track that I'm using so i can just solder the rails to the top of this part. The disc is a snug fit inside this and will be connected (by a cranked arm) to a stepper motor below.

Hi Izzy, thanks for the thoughts. I understand the point about heat dissipation and you are right, my method has left very little copper to spread the heat around. I'm not entirely convinced that a sliver of brass will have much impact on the thermal mass of the joint, which I would expect to be dominated by the rail. I don't quite get your point about it being a stronger joint though - why would rail soldered to brass, soldered to copper be stronger than rail soldered to copper? The weakest link will still be the the copper to fibreglass joint, just as you point out. Or is that what you mean and that my method is more likely to damage this? If so you are probably right. I'll see how my experiments go and then decide if a different method is needed. As an aside, these aren't paxolin - I don't think I've ever even seen FR2 board! It's more difficult to get hold of these days because hardly anyone uses it for electronics any more.

Hi Tim. Yes, it's the same code 40 bullhead rail used by the 2FS crew on moulded track bases similar to their easitrac but at 9mm gauge. It's available here: http://www.britishfinescale.com/ So far the range of turnouts is limited (it was only launched a month or so ago) but I'm assured that others will be available soon. It doesn't matter too much to me as I'll be making my own point work with components from them.

Track at the baseboard join after laying, cutting, disassembly, getting bashed around a bit to test how strong the rail ends are and finally bolted back together on an uneven floor. Looks pretty well aligned to me.

Useful to know, thanks. I'm going to deliberately try to break the ones I've done to see how they perform. If they come of I'll drill through the chairplate and put in a brass pin as Ray suggests.

Yep, I had one abortive attempt on an old door but I never got much beyond early planning with that so I don't think it counts. I have been known to go to fancy dress parties as Sherlock!

Hi Colin, Thanks. Yes, they are brass. My lathe is a CNC converted Myford ML10 and my CNC mill is one that I built myself. Neither are big or powerful but they are accurate. That said, I did stuff up the first attempt at the roller gauge (forgot to account for the width of the rail - oops!) I'm not sure, thanks for sharing your experience. I've not done board joins before (or any railway modelling for that matter) but It had crossed my mind that I've not left all that much area for the copper chairplate pads to bond to the FR4. I haven't allowed for any other fixing method at the moment but I'm treating this join as an experiment. That's why I'm only laying track about 30cm either side of it for now and then I'll try abusing it to see how it stands up. I didn't want to use screws because I couldn't see how to hide the heads. Pins might be ok though and would make convenient droppers ... hmm

(cue west country accent) This evening I have mostly been ... making gauges: And yes, the roller gauge is supposed to be asymmetric.

I'm shocked that you even have to ask! Yes - I was just posing it for the photo.

Today I spent most of the morning finding and fixing a problem on my mill and then face milling a sheet to give myself a perfectly level base for doing thin sheet work on. When I finally got it sorted I got down to railway business. For the most part I'm using fiNetrax track (a new N gauge track offering which is similar to the 2FS Easitrac but with 9mm gauge and some nice features to make the pointwork even easier to assemble). At the board joins I'm taking a leaf out of the 2FS book and milling some little bits of track base in copper clad FR4. This will allow me to solder the rails down for the last few sleepers before the join and will give a much more robust section of track than the plastic sleepers I'm using everywhere else. Here is the mill at work: And here is the joining section roughly in place with some bits of rail to check the alignment. I've milled it so that the copper is removed from the top of the sleepers leaving just an area directly under the rail which matches the chairplates on the plastic plain track. The part is designed from the templot file and follows the gentle curve of the line in this section. This part is now being stuck to both boards simultaneously with a very thin layer of epoxy. Once this has cured I will tidy up the burrs on the copper chairplates and solder the rail in place. Only then will I make the cut to separate the boards. And remember children - Lungs, eyes and ears are for life and not just for Christmas

You can measure the speed of a Permanent magnet DC motor without additional sensors. You disconnect the power briefly and measure the voltage induced in winding - this is directly proportional to the motor speed. This is what Back EMF DCC decoders do, try these linksas a starter: http://ww1.microchip.com/downloads/en/devicedoc/41233b.pdf and https://sites.google.com/site/hobbydebraj/home/dc-motor-control-using-back-emf-sen. You can also count commutation ticks, but this is a bit harder to implement reliably.

As I understand it the difference is between extruded and cast acrylic sheet. Explanation of the differences here: http://www.bayplastics.co.uk/acrylicsheet_faq.htm

But for one word this was 'nearly' the post of the day.

Was it the ice cream that was expensive - or the car that you didn't notice and accidentally crushed just out of shot to the left? Yeah, 1:1 scale war gaming can get a bit pricey.

Agreed. I don't draw the prototype - I draw the model (with whatever thickness compromises I need) but pretending that 1m in sketchup is actually 1mm on the model avoids the silly radius problem.

I find that my railways and my archery cost about the same. However my other hobby of building CNC machines, 3D printers and so on .... that's a tad more!

Yes, that is much lower than the quotes I got in the UK. I got quotes in the range of £100-200 per 3 sheets of 900x600. Needless to say, at that price I would have got my saw out!