Twinwoods & Bedford

[RudyB]

Twinwoods & Bedford - 01 - Layout Design

Together with hobby friend Nico the plan is to build a new layout in a spare bedroom. In this thread we like to post progress from time to time. We’ll go through all the steps, from first ideas, to design, to (3D) simulation, to woodwork, to track laying, mount point servo’s, add train feedback and create computer control. The plan is to add some videos along the way too.

No scenery in that list? Well … to be honest, creating beautiful scenery is not our forte. To us the emphasis of the hobby lies on the design, woodwork, track laing and then the automation. We’ll probably drive around with too many trains on too much track to make it look like anything ‘real’.

This is a link to video 01 - Layout Design

These were our criteria:
Available space: 4040 x 3700 mm
Scale: HO
Rail: Peco OO 75
Minimum radius: 600 mm
No need for much scenery
We like to have a lot of rails
It doesn’t have to resemble real world
We like to be able to drive around on a loop
We also like to drive dead end to dead end
We like to have a train viaduct, it enables a longer available track in the same space

This is the end result of our design efforts:

[Mountain]

A lot of thought has gone into this and I like it! Yes, a compromise and you may find more compromising to come but the general idea is excellent as it provides hours of operating enjoyment with the only downside being easy access without ducking under of having a lifting portion. (Lifting portions do work but can need a fair bit of adjusting every now and then as the general humidity and overall temperatures change during the year so any lifting portion should hve this in mind in its design. Ducking under is an option)...
A nice design though for passenger trains, especially DMU's.

Not sure how much all that track costs. Worth it though!

If track costs are high one can always opt for a double track main running line instead?

[RudyB]

Thanks for your feedback Mountain. Track costs have already been spent as this is not the first layout we build, the previojs one has just been broken down and this one is going to be somewhat smaller in a smaller room.

The plan is to have a lowering portion (rotating on hinges) in the straight track at the door, to allow for easy access without ducking.

[Mountain]

It should be good. I am used to hiring hinge positions to have lifting bridge sections though I actually have never had one myself on my own layouts.

[RudyB]

Twinwoods & Bedford - 02 - Table Design

The track layout has round shapes. We like the tables to follow these rounds. This means a lot of saw work, with good accuracy.

The plan is to first draw the table lines on the wooden plates such that it’s easy to follow them with a jigsaw. We’ll first make a drawing with the correct dimensions in Fusion 360. Using a 10 cm grid we can transfer the table coordinates at the grid intersections to the wooden plates, on which we first also place the grid dots. Then we play ‘connect the dots' and we'll have the real size drawing on the wood.

The plus of using Fusion 360 is that once we have a drawing we can simply turn it into 3D shapes and get a good feel for how it’s going to look.

Another option could be to print the layout in real size via SCARM. But then to accurately place all A4 sheets on the wood and transfer them to saw lines is still a challenge.

We’re curious what other methods have been used to transfer the layout to the table and create accurate saw lines?

This is a link to video Twinwoods & Bedford - 02 - Table Design

[RudyB]

Twinwoods & Bedford - 03 - Widen the Aisle

We had performed tests to investigate if we’d be able to pass through a narrow space of 30 cm. The tests were performed with two desks spaced 30 cm apart. The tests were positive, as in ‘it’s doable’, but deks are only 74 cm haigh, which means you pass them below your bum, with your legs. Yesterday we were able to perform similar tests with tables at the intended height of 110 cm … that’s a whole other matter. Now you pass the tables above your bum, with your belly. How come that does not fit nicely anymore? I have no idea.

Conclusion of the test was that we need to modify the layout. To create more aisle space we had to give up our criterion of a minimum curve diameter of 120 cm, we made the inner curve around Bletchley station 100 cm and we also created a small bend just after the turnouts into Bletchley. This had the desired result … we now have a 50 cm aisle width.

In the process the idea popped up to extend Bletchley station over the curve, creating a tunnel. This helps make the layout somewhat more interesting. It’s not decided yet … let’s say this has an 80% probability.

This is a link to video Twinwoods & Bedford - 03 - Widen the Aisle

[Mountain]

Now that does look a lot more practical. I loved the plan before but thought it was a little tight, but now you have some walk around room.

I personally find that my layouts from the past or the one I have now (Though it is folded up and stored at the moment) tends to end up as a table to put things, so I need some workshop space more than I do layout space... As all these verious exciting projects of mine tend to need space... Which is why a lot of the time I have nothing happening when I need to keep things tidy!
So what I am saying is a test track for me is better than a scenic layout, though I do like a scenic layout, but if you can plan ahead, somewhere to put things down on under the scenic parts is a good plan, and my last layout had a low level table underneath one part which came in handy, though I seem to recall I replaced it with a chest of draws as I ended up with more model railway things...

[Flashbang]

In OO/HO you need around 60mm minimum height taken from the lower level rail top to anything passing above the lower rails. 60mm is not a great amount, but that is the minimum and getting your hands inside the tunnel etc may be almost impossible for rail cleaning and rescuing anything that's derailed!
Also the inclines should not be greater than 1 in 30 and ideally be 1 in 60, especially where curves are involved as they add extra drag. Thats for every 1 unit of rise you need 30 (or 60) equivalent units of length - i.e. rise 1cm needs minimum 30cm of length.

[RudyB]

Twinwoods & Bedford - 04 - Simulation with EEP

Before putting the saw into the wood, constructing tables and laying track we planned to do two simulations, one in Traincontroller and one in the very nice EEP 3D (model)railway simulator, which this video is about.

Any possible issues found in this stage will be much easier to resolve than after the tables are mounted and track has been laid. Besides … it’s just fun to create a layout in EEP and have trains run fully automatic, thanks to the additional software that was created in a joint cooperation with German hobby friend Frank Buchholz.

So … what are we looking for? Well, mainly if the layout looks nice … in our eyes that is, some will think there’s too much track and too little scenery, but that’s how we like it . We also want to check if train flow is smooth, varied, and without any traffic jams or hiccups, or opposite to see if there are any tracks that are never/seldom used.

This is the link to video Twinwoods & Bedford - 04 - Simulation with EEP

For those who like to try out EEP:
This is a link to EEP on Steam.
This is a link to the free EEP Automatic Train Control software.
This is a series of videos on EEP automation

[RudyB]

Twinwoods & Bedford - 05 - TrainController

The second test before sawing the tables is to try the layout in TrainController. TC is a Windows program for control and automation of digital model railways. It has a simulator mode which makes it possible to already test a layout before it is physically there.

TC uses block control. Every block has an entry sensor. These can be reed switches operated via a magnet under the train, or current measurement, or other. The sensors tell TC when a train runs into a block. If it has to stop in this block, the brake marker is the point where the train starts to slow down, until it reaches the stop marker. Distances between the sensor and the brake- and stop marker are user specified.

Once the layout has been divided into blocks, ‘Schedules’ can be defined. These specify which trains should drive where. Once the train reaches the end point of the Schedule, TC selects a new Schedule from a list of ‘successors’. This way fully automatic traffic is created, while it still is possible to drive trains manually, in between the automatic traffic.

The test is performed to see if traffic keeps flowing, if there are no hiccups, or deadlocks, or if there are blocks where no train ever comes. All went well … so … it’s time to start sawing the tables!

This is the link to video Twinwoods & Bedford - 05 - TrainController

[RudyB]

Twinwoods & Bedford - 06 - Sawing the Table

The two simulations (EEP video 4, TrainController video 5) showed us that this layout can have an interesting train traffic flow. This gave us the confidence to now start sawing the wooden plates for the table.

The challenge was to transfer the drawing from the PC to the boards to have the lines to saw along. We did this by first placing a grid of boards over the layout drawing. This enabled us to read out the x,y coordinates of strategic points per board. Two points are needed for a straight line, three for a curve. We used a bendable plastic strip to draw smooth curved lines on the board.

This is the link to video Twinwoods & Bedford - 06 - Sawing the Tbale

[RudyB]

Twinwoods & Bedford - 07 - Mounting the Table

After having sawn the 9mm wooden plates in their respective shapes the tables can be mounted.

Along the wall the plates rest on a full length beam. The peninsula and the aisle side of the tables rest on legs, connected via beams to create a support frame. All legs have height adjustable feet.

In the meantime the lower and upper tables and the peninsula are mostly done. What’s left are the two ramps. These will be sawn out of 3mm board because they need to be flexible. The ramps are curved and need to be twisted some to mount them flat to the surface at both sides.

This is the link to video Twinwoods & Bedford - 07 - Mounting the Table

[RudyB]

Twinwoods & Bedford - 08 - The Table is Ready!

This week a hardware milestone has been reached: the woodwork for the table is finished.

The bridge that can be opened at the room entrance has been mounted with two hinges on one side and a sliding lock at the other.

The two ramps are height adjusted and supported to the mm. One has a 2% inclination, the other 3%, we trust trains will be able to drive OK on these.

A few pieces of cork layer still have to be placed and then … let the track laying begin!

This is the link to video Twinwoods & Bedford - 08 - The Table is Ready!

[RudyB]

Twinwoods & Bedford - 09 - A Paint Job & Turnout Servo Mount

We experimented with several rail bed and ballast options. We don’t plan to ballast the tracks 100%, which we know looks best, but we’re not that much into scenery and 100% ballasting is going to be a whole lot of work. We think we found a nice compromise that’s a lot less work and which also doesn’t require a second layer of cork under the tracks to heighten it.

The only thing needed is to paint the cork in a dark brown / rusty color, to which later maybe some spots and streaks of darker almost black can be added to taste. So … that’s what has been done past week, the cork has been painted with a Palissander stain.

The first track pieces and turnouts have been placed too, accurate to the mm. The video shows how we do the turnout servo drives.

This is the link to video Twinwoods & Bedford - 09 - A Paint Job & Turnout Servo Mount

[RudyB]

Twinwoods & Bedford - 10 - Turnout Servo Drive

This video shows the servo drive we use on the layout in more detail. The servo motor is an SG90 180°. It fits snugly in a 15mm aluminum U profile, in which two screw holes are drilled as well as a 1mm hole that serves as the pivot point for the pin that moves the turnout. The pin is an unfolded paper clip.

We use Arduino for DCC control, loaded with the MARDEC software that can be downloaded for free from www.arcomora.com. This software is a DCC servo- and accessory decoder and it’s also used to tune the required servo angles for the two turnout positions.

This is the link to video Twinwoods & Bedford - 10 - Turnout Servo Drive