Les Green

We will check this out when we can. The baseboards have now been taken down to work on the electrical stuff underneath.

Which three columns are you referring to. Some of the photos show a lot of camera perspective distortion. The actual columns on the model all look to be near enough vertical.

The next stage is to make the station roof. The roof trusses sit on small trays on the columns. This allows the roof to move 5mm in any direction to allow for baseboard movement or temperature effects. The 3D drawing gives the theoretical position of all the trusses but I needed to know the actual positions of each tray rather than use the drawing. The trays will not be in their correct position if the column is not exactly vertical or the column is rotated. The roof will bein eight sections and a template was made for each section. The eight templates with tray positions and trusses marked The support pieces were placed on the platforms. These gave the correct height for the templates and prevented them from sagging under weight. and the templates placed in position on their supports Holes were drilled at the tray centre positions with a small tool that fitted to the rear of each tray. About 32 holes had to be drilled in the eight templates. Some holes being difficult to reach!!! Having drilled the holes in the template the roof trusses can be made to the correct spans and the roof built up on the template. But that is another story. The maximum error of actual tray location compared to theoretical position was about 5mm. Most were within 2mm.

At long last we have finally fitted the roof support columns to the platforms. Each column was supported in a jig to ensure it was perpendicular to the platform in two planes. And here I am fitting the final column. The row of columns on the North side of the platforms The central row of double columns The columns at the South side of the platforms and finally a close up of a triple set of columns, complete with dust, rust and pigeon muck (00 scale pigeons are now on order)

Homework done! I scanned some photos of the hotel as it was in its early days. Photos which show the original window frames, which are different to today's double glazed units. One of the photos must have been taken in summer time, all the windows are open!

A bit of progress with the 3D model of the North Western Hotel. The two central towers are now complete. They are not quite mirror images. One of the towers has two chimney stacks with 7 chimney pots on each stack. The other has one stack with 7 pots on and one with 6 pots on. Never assume anything!!!

I have checked the web thicknesses and they are all the same. Guides in the rollers? I have thought about that and may get a channel turned into each roller. Tried single pass and multiple passes. Not sure which is best. May be two passes, one in each direction.

I am about to start making the first set of trusses for the station roof. The top part of the truss is a brass 'H' section girder. The span is about 700mm and the radius is 550mm. The first batch of 16 have been curved in a set of rollers. Most of the girders are within a tolerance of less than a millimetre over the central part of the girder. The outer few milimetres of each girder is a bit ropey and will be removed. Unfortunately one or two of the giders have twisted during the rolling process. Difficult to explain and difficult to photograph. However, looking at the drawing below, the radius of curvature of the girder should be in the YY axis. One or two have curved in the Y'Y' axis. I tried to ensure all the rollers were parallel and the girder was fed into the rollers perpendicular to the rollers. It seemed random as to which were OK and which were twisted. Even when I managed to set the rollers in one position a bad one could follow a good one with no roller adjustment. Anybody any ideas what I am doing wrong.

A sewing room for John's wife. But that is another thread!

I was about to say 10mm less than the outside dimensions, then I realised you meant the shed and not the hotel model! The shed internals are 5m x 22.5m!!

Ground signals and hotels. The 'Little & Large' of railway modelling.

As you can see the hotel sits in a hole in the baseboard which is 16mm deep. The concept model should have had 1/2mm clearance all round in the hole. The width was perfect and has 1mm front to back movement. The length just fitted in the hole with no clearance. The 1259mm long model was 1mm too long - failure!! (blame it on the thickness of the glue!)

The 3D CAD model of the North Western Hotel is progressing well, as I have shown in a previous post. I have now completed a 'proof of concept' model'. The model is about 1.2m long and is huge! Shown in the back garden on completion. The view no one will see as it will be almost hidden by the station roof! And finally in positon on the Lime Street layout. I have omitted the roof and pinnacles. They were not needed to prove the hotel concept. I have never made a model of this size before. Awesome!

Now for the really mind blowing post regarding the Lime Street Layout project. John recently moved house so that he could have a big enough garden in which to build a shed to house the layout. The shed was started in January of this year and we had the opening ceremony yesterday. Six months of building. The site is cleared and measured out The pile driver moves in! And the concrete floor is laid. Inside is almost complete. Awaiting the doors Which are finally fitted A few more internal walls to build And another internal wall And the room is completed and carpeted. John finally brings the layout to its new home. I said it was mind blowing!!

Prior to the above mentioned opening ceremony a bit of progress was made on the station structure. The completed columns were trial fitted to the station platforms. They will now be removed for painting before their final glueing in position. Also I managed to knock up the first of the roof trusses on the morning of the opening ceremony. Only another 39 to make! The remainder cannot be made until the columns are fixed. Only then can we measure the truss span dimensions. The one I made for the opening ceremony was made to the drawing dimensions. Hopefully this will be correct to at least one of the final measured dimensions!!

The rapid prototypes we made for Lime Street were done using the stereolithography technique. Basically a bath of liquid resin is used. The resin solidifies where two lasers intersect. The method Shapeways use seems to be based on solidifying a powder. The resolution we got was, if I remember correctly 0.01mm, where Shapeways quote 0.1mm. If we had to do some more items Shapeways looks like a place I would try out, if the prices are acceptable. In the early days of stereolithography the resins used were hygroscopic, meaning they absorbed water, resulting in a short shelf life. The models first went soft after a few weeks, then very brittle. Modern resins last a lot longer. Painting the models prevents water absorbtion and therfore prolongs their life. Our masters were made about four years ago and show no signs of deterioration despite being unpainted. All our drawings were produced in AutoCad in 3D. Importing the files to an .stl format is relatively easy. From these files the models are produced. Unfortunately I can't comment on price or where we had them made. It was a friend of a friend of a friend sort of job. I can help on how we produced the 3D drawings if required. That was a me job!!

I think there are times when I wish Lime Street had a concrete slab roof!! Les

Also looking forward to getting my hands on the layout in the not too distant future. I can then make a restart on the station roof.

All the signals on the layout are made by Steve Hewitt and are all fully operational. The main signal gantry at the end of the platform is particularly spectacular. No doubt Steve will add more details to this particular topic when required. Other general types of signals on the layout include, colour light signals, ground signals, theatre indicators. All working!

The current status of the CAD model of the North Western Hotel.

Sometimes, that is all I can say. I am just one person doing the roof and the hotel. Steve is the signalling man, Geoff the sofware man, Chris the track and building man. John does everything else. We had a bit of a chat together the other day to see who went the extra mile. One person made some of the links on a caravanning holiday, one person designed the software on holiday. I designed part of the layout on a flight to Australia. What a mad lot we are!

The next stage is to permanently locate all the columns on the layout. Once they are in their permanent position we can make eight roof section templates showing the exact location of all the support trays. Eight, as the roof will be made in eight sections. The CAD drawing shows us where the trays should be, but we need the absolute positions before we can make the roof trusses. Once the templates have been marked up the roof will be on the go, followed by the hotel, followed by.........

Finally for today we will take a look at the end screen structure. The south arch and the north arch have end screens at the street end of the station and the throat end of the station. The south screen at the street end requires the following support structure. This again is the CAD model of the support structure. And the girders manfactured for the end screen. The double girder at the bottom is almost a meter long! And just for the heck of it the station clock!! The clock will be a working clock and will keep accurate time by being linked to the atomic clock at Greenwich(?). Cos we can!!

The roof girders are simple 'I' section lattice girders. Each girder is made from three etches, one centre lattice plate and the two end plates. Again making a single girder took time. In fact on my first day I managed to make two girders. Another jig was made to speed up the process. The jig was made from Tufnol and used three cams to clamp the three girder items in place. The clamping jig. and here with the components clamped in position ready for soldering. Using this method I managed ninety girders on a good day! To show the enormity of the task here are a few of the girders. Some single length and for aditional strength some double length girders The photo show only 41 double length girders. We actually made 269 plus 156 single length girders. A total soldering run of about 250 metres!!!

The station roof is supported on large bow string roof trusses. Each roof truss has several links. The links on the full scale station are made up of several formers and four lengths of L section girder. On the model we have substituted 0.6mm wire for the L section. This is the CAD drawing of one of the roof trusses. As can be seen there are lot of links to be made. To speed up the manufacture of the links several jigs were made. So this is how it was done. Firstly the jig is assembled using three support pieces and two end plates. The end plates are slotted to allow the fourth support plate to be located later in the process. Then the formers are slotted in to position on the support pie\ces. . The fourth support piece is then located on the formers and an extra end plate is added and locked in position with a wire staple giving a very stable jig with all the formers locked in position. The pre bent wires to the correct radius are soldered in position. Once the four wires have been soldered in position the end plates are removed followed by the support pieces and we are left with one roof truss link. Easy! Then in to the dishwasher to clean it up! Except there are 7 different lengths of link and 740 links are required. Without the jigs one link took all of four hours to make it was so fiddly. With the jig we got down to about five minutes per link on a good day. Taking all the links into account we soldered about 13000 joints and used 6000 components! To give an idea of the enormity of the task this is about half of the links! Next, the roof girders.