OO8: 4mm Scale, 2ft Gauge Track

One of the problems of modelling in OO9 (9mm gauge track in 4mm scale) is that often the track isn't really to scale. 9mm track at 4mm to the foot is 2' 3" but narrow gauge railways varied quite widely in their choice of track gauge. In Britain possibly the most common gauge was 2 ft meaning that 9mm track is 1mm too wide.

The bridge I'm building for my entry to this years Dave Brewer challenge carried a 2ft gauge railway and given I'm aiming for the smallest entry category (to make it easier to transport on the train) I thought it made sense to produce track to the correct gauge so I give you my first attempt at OO8 track (8mm gauge track modelled at 4mm to the foot).

As you can see this combines the numerous experiments I've been blogging about recently (here, here, and here) to produce a short test piece. Producing actual track using rail spikes in this scale is exceedingly time consuming. I've probably spent about 10 hours producing this small piece, although by the end of that I'd got a system going that means producing more will be quicker but not by much. On the plus side the track is to scale and an accurate representation of the real track I'm modelling right down to the number and placement of rail spikes. The spikes look a bit too big in the photos and they probably are, but in real life they blend in quite well.

I'm really happy with how the track has turned out, although it has meant that the number of hours I thought I'd need to build the diorama for the challenge has increased quite substantially. I should still have enough time though so I'm not worried.... yet.

Clayton #5843: Now With Wheels

While the parts on their own looked good I thought it was worth showing you how the loco looks roughly assembled with wheels fitted.

Obviously the axles need cutting down in length, but they were just fitted to test that the bearings were nicely aligned and that the chassis would roll freely. Unfortunately I found that the holes for the bearings were slightly too small. I'd intended brass bearings to be a push fit into the print but I had to ream out the holes slightly for the bearings to fit. This was easy enough to do for the wheels, but the holes for the layshaft bearings are harder to access so they will need to be made slightly bigger on the next print to make life easier.

First Prototype of Clayton #5843

I had a Shapeways order arrive yesterday which should give me even more things to blog about so you don't get bored with my bridge building experiments. There were parts for quite a few new models in the order but I'll start with showing the parts for the Clayton battery electric locomotive I described back at the end of May.

From an initial look at the parts they have printed quite well with only a few places that might need smoothing down before painting. I have, however, discovered two issues. Firstly with the print as I designed it I can't actually fit the motor, and the fixing between the top and bottom isn't perfect.

As the motor I'm using doesn't have any fixing holes built in I designed the mount to hold it in place with a friction fit. Unfortunately I didn't leave enough space to angle the motor down through the front part of the mount. Fortunately I think I'll be able to file down part of the mount to fit the motor, and then update the digital model when I know if that works or not.

While the top and bottom parts fir together well, the upper part is ever so slightly bowed. While only slight pressure is required to flatten it this isn't possible once the parts are fitted, and the mounting screw holes are at the wrong end to make any difference. Fortunately I think a slight redesign of the motor mount to provide a slightly tighter fit of the two parts would cure this so again not a real problem.

So even with those issues the model looks promising. I'll clean up the print and then start trying to build up the model. The bottom part will actually need painting before assembly (no way of painting behind those wheels among other things) but painting the top part will have to wait until the etched parts arrive. Anyway there is no rush as long as I'm enjoying myself.

Rail Spikes

So, having arrived at a much better approach to painting rusty surfaces I've now turned my attention to the track, specifically how I'm going to affix the rail to the sleepers. The bridge I'm using as inspiration for my entry to the Dave Brewer challenge, which is still a secret for now, uses a fairly light rail held to the sleepers using metal spikes.

All the track I've hand built before has used copper clad sleepers and I've simply soldered the rail in place. Clearly this won't work for rail held down by spikes. So firstly I'm going to use sleepers made from plywood (hence my experiments at painting wooden sleepers) but more importantly I need a source of spikes that will hold the rail in place. My intention is to use code 40 rail, which is pretty small, and I haven't been able to find anyone who sells spikes for such small rail. What I did find though was a series of articles in NG&IRM Review by John Clutterbuck (which were republished in 2008 as a free download) about making track. While John models in 7mm scale using larger rail, he happens to make his own spikes from..... staples.

The approach I've taken mostly follows John's description but with a few changes to take into account the smaller rail size.

I bought the smallest staples I could find but they are still made from quite a thick metal (about 0.45mm) so having used masking tape to keep them together I filed the edges down a bit to make the corner a lot thinner (I had to use diamond files to really make much impression on the steel). Once I'd filed down both sides I used a set of track cutters to cut off the legs of the staples keeping just a tiny amount of the curve. All the spikes were then separated from each other before soaking for about 5 minutes in nail varnish remover (the stuff I "borrowed" from my wife is acetone free but I'm guessing acetone would also work) to ensure the metal is clean and that the plastic coating applied to staples has come off; you end up being able to see the bits of plastic floating in the solution. The spikes were removed from the nail varnish remover (a magnet makes this nice and easy) and dried before being soaked in Carr's metal black. They turn black almost instantly if they are nice and clean but again I left them for about 5 minutes, before removing and drying them.

I still need to figure out the best way of actually using the spikes to fix rail to sleepers but for a quick test I drilled a small (0.45mm) hole and pushed a spike through the sleeper, added the rail so I could accurately drill a second hole for the second spike. Once both spikes were firmly pushed through I held them in place with a drop of superglue added from below. Once this had dried I cut off the excess spike and filed them flush with the bottom of the sleeper.

For a first attempt at making and using rail spikes I think this has worked well.

Just Rust: Take 2

On reflection, and given the very helpful and constructive criticism from Paul and Iain, I've gone back and had a second go at rusting a bit of rail and girder. While the powder based approach might work well for rail dumped in a bog for a few years I admit that it wasn't so good at representing rusting surfaces which tend to discolour without such serious pitting.

On this second attempt I again started with red oxide primer and then started to add shading using the same paints as before. At this stage I wasn't entirely convinced that I was getting anywhere but the addition of some weathering powders (rust and dark earth) seems to have pulled things together nicely. Not only does the texture look more convincing but I think the colour is better as well. Hopefully you all agree?

This episode reinforces the main reason I enjoy blogging and getting comments; without Paul and Iain's feedback I may well have just continued with my first approach and the final model would have suffered as a result.

Just Rust

I grabbed a few minutes today (spread out a bit) to have a crack at another experiment which I'll need for the bridge I'm planning for ExpoNG. I'm reasonably happy with adding rust as a detail to a model but I've never tried to paint an entire item completely rusty. There are plenty of rust coloured paints and washes available but the problem is you need texture as well as colour variation as a well rusted surface tends to be pitted. On the bridge I'm modelling there is quite a lot of rusty girders and flat-bottomed rail so I needed to experiment a little.

What you are looking at here is a piece of girder at the back (which is just 3.2mm tall) and a piece of code 60 rail at the front. Both have been treated in the same way. To get the pitted effect I first sprayed on a layer of red oxide primer before gently sprinkling on some light weight hydrocal casting powder (it was the finest stuff I had to hand that didn't want to clump) to the wet paint. I then knocked off most of the powder, allowed the paint to dry for a second or so and then sprayed a second layer of primer. This seems to give a really nice texture although I might have added a bit too much powder to the rail sides. Once this was all dry I liberally dabbed on some MIG Productions Standard Rust Effects which provided some nice variation in colouring and shading. I then dry-brushed on a small amount of RailMatch Light Rust (#2404), before some final dabs of a rust wash from Flory Models.

The photo is very unforgiving and from a normal viewing distance the texture is less pronounced and I'm fairly happy with how they look.

Bridge Over Troubled Water

Having really enjoyed my trip to the 009 Society AGM back in April I've made the decision to attend the other big narrow gauge modelling show of the year, ExpoNG, at the end of October. As well as going to enjoy the modelling on show and to socialise I'm also hoping to have the kit for the Hudson-Hunslet ready by then as well which if it's a success will help with the expense of getting to Kent for the show.

ExpoNG presents a number of awards each year for layouts but they also have an open modelling competition, the Dave Brewer Memorial Challenge. Unlike the 009 Society competition this isn't just about locomotives or rolling stock and in fact the rules change every year. This year the competition is all about building a bridge. Specifically the rules are:

1. The model bridge may use any scale and gauge combination, as long as it represents a narrow (ie less than 4 ft 8.5 ins) gauge, with a maximum gauge of 45 mm.
2. The model can be any type of over or under-bridge and should be complete with abutments and track.
3. The model may be wholly scratch-built, or use parts from kits or commercial models, but no unaltered kits or commercial models can be entered.
4. To ensure we can fit entries into the available space please use these maximum sizes:
1. 50 cm by 25 cm by 35 cm high for gauges 32 mm and above, to a maximum of 45 mm.
2. 40 cm by 20 cm by 25 cm high for gauges 14 mm and above, but less than 32 mm.
3. 30 cm by 15 cm by 20 cm high for gauges 9 mm and above, but less than 14 mm.
4. 20 cm by 10 cm by 15 cm high for all gauges below 9 mm.
5. The model should not have been entered in any previous competition.
6. To be eligible, completed entry forms must be received by 31st August 2015.
7. To be eligible, models must be presented for judging at Expo Narrow Gauge 2015.
8. A prize, including one year’s subscription to Narrow Gauge World, will be awarded to the winner.
9. The judges’ decision is final.

Given that I still find producing effective scenery a lot more challenging that building wagons etc. I thought building a small diorama (with a bridge) to a deadline would be a good idea. I had originally thought about building something in O14 so I would have somewhere to display the Clayton battery locomotive, but as I'll be travelling down on the train I'm thinking a small diorama would be better especially as it's going to need a sturdy box to transport it.

I have decided what I'm modelling but for now I'm planning on keeping it as a surprise for the day. I will, however, blog about the build as I go along as there will be a number of experiments that I'll need to make before committing to the final version. Without describing the bridge in detail I can say it's fairly decrepit looking and crosses peat coloured water. This means that I need to be able to model (among other things) peaty water and sleepers that have been weathered almost to a silver colour.

Having never tried to model water before I decided that this was likely to be the main problem I'd have to overcome. There are a number of products available for modelling water but they all seem to produce crystal clear water which isn't what I wanted. Asking around on the forums and most people suggested that I'd be best using a number of layers of yacht varnish to create the effect I wanted but I've never had much luck varnishing furniture so I didn't really fancy this route. The other option was to add colour between layers or into the water products, but again I couldn't find many people who had done this to model what I was after; the one exception being the stream on Tom Dauben's Dunbracken layout (a good photo of the stream can be found here). Tom told me that he'd used the Woodland Scenics Realistic Water and Water Effects products to create the stream with colouring applied to the stream bed and between a few layers. Armed with this information I set out to do an experiment or two.

My original intention had been to paint the stream bed (in this experiment a bit of white card) and then pour the water to see how it worked, but while browsing in WH Smiths I discovered that Winsor & Newton do a peat brown ink. So armed with the ink, some paints, and the Realistic Water I did an experiment. I first painted patches of the ink and burnt umber acrylic paint on the cardboard. I then coloured the water using a few drops of ink before pouring it onto the cardboard (the weird chunk at the top I'll come back to). The colour looks better in real life and what I've found is that the ink works well not just for colouring the water but helping simulate depth where I used it to paint the cardboard. the burnt umber patch seems too dark and different from the water to be believable, although that could just be because you can see the edges so clearly. The weird chunk is because I had a little bit of the mixture left so added a bit more ink to make it darker and then left it to dry in the pot. Once dried I removed it from the pot and decided it was way too dark. Unfortunately I then put it down on top of the experimental pour and left it there overnight. The following morning it was stuck. Anyway I'm really happy with this first experiment. Obviously I'll need to repeat it using some proper scenic materials (i.e. plaster) for the stream bed, and probably multiple layers of water to get more depth but it certainly appears to have promise.

As some of you may remember it took me quite a few attempts to get a well worn wood effect sorted when painting wagons and they are a very different colour than exposed sleepers would turn (or at least I think so looking at photos etc.), so I wasn't looking forward to coming up with a new approach, but I think I've found something that works reasonably well.

The sleepers aren't the right size as I just chopped up and distressed some coffee stirrers but hopefully the painting will work regardless of the size. I started by soaking them for a minute or so in a 10:1 mixture of isopropanol and Indian ink. This doesn't turn them jet black but allows the ink to settle into distressed bits of wood quite well. I then painted the sleeper using the peat brown ink used for the water. The black sections show through giving a nice variation and depth to the cracks etc. I then followed this by dry brushing with dark sand, ivory, and finally gun metal. This approach seems to work nicely as close to you can see lots of the grain and colour variation, yet when viewed from a distance, especially with the light falling on them, they look very light in colour which matches what I was hoping for.

So I might not have actually modelled anything but hopefully I now have a good idea of most of the techniques (although not all) that I'll need to complete the bridge for the challenge.