Quarry Hunslet: Building the Main Frame

I know I said I wasn't going to rush the build of this model, but the combination of a well thought out kit and annual leave means that it's coming along nicely and today saw the assembly of the main frame.

All but one of the parts (the one piece saddle tank, smoke box, and firebox casting) are from the etched nickel silver fret and such is the quality of the kit that they required almost no tidying up before assembly. The majority of the time was taken up with cutting slots in the front and rear buffer beams to allow me to fit couplings. These had to be carefully measured and then I drilled the slots out by hand using a 0.55mm drill bit in a pin vice. Given the thickness of the nickel silver this took me well over an hour, but it was time well spent as I will want to couple the loco to wagons and carriages and there is no way I could have accurately cut the slots after assembly.

For me at least, one of the selling points of this kit is that it can be assembled using super glue rather than having to be soldered together. I'm sure that soldering would produce a stronger frame, but while I'm happy to solder wires together the idea of soldering metal at right angles scares me, possibly more than the thought of assembling the valve gear. So for this build at least, I'm going to stick to super glue and concentrate on getting a free running model. I can't be bothered with doing a video for today's post, but the added weight of the frames and the whitemetal casting have definitely improved the running of the motor unit, and it really is starting to look like a steam locomotive now.

According to the instructions next up is assembling the motion, and in comparison to the four steps in the instructions I completed today, there are 11 stages to assembling the motion so it might take a while before I have anything new to blog about.

Quarry Hunslet: Building the Drive Unit

It's been an unusually productive day on the modelling front. Not only did I experiment with automatically controlling the track power, but I've also found the time to start on the build of the Brian Madge Quarry Hunslet kit that arrived a few days ago.

The first stage in building the kit is to assemble the basic drive unit from it's ten constituent parts (the photo below shows 11 parts as there is a spare drive belt). While the steps are all straightforward the small size of the unit (it's stood on a 1p piece in the right hand photo) makes this quite a fiddly task, but as you can see I got there in the end.

The paint job, especially on the wheels isn't particularly good, mostly as I did the painting before assembly (no point trying to do it after the pickups etc. are fitted) but then of course had to handle the item quite a lot. This isn't the end of the world though, as I can always touch up the paint and, more importantly, very little of what you can see will be visible on the final loco as the outside frames will hide the wheels etc. The important point of course is whether or not it works, and as you can see from this short video, it runs backwards and forwards really nicely (it's being controlled by the same circuit as described in this mornings post)

Motive Power

Those of you who have been reading this blog for a while, might remember that the main motivation behind modelling Jerusalem in N gauge was that I wanted a roundy-roundy layout where I could just watch the trains go by, as I'm not really into the whole shunting business. This preference for just sitting back and watching the trains hasn't changed which leaves me with a bit of a problem, as the new layout is so narrow that it could only ever support an out and back style track plan and personally constantly turning the controller on and off to operate such a layout sounds seriously tedious. To try and solve this problem I've been experimenting with some electronics to see if I can control the layout automatically for those times when I just want to sit back and watch.

What you can see here is my first attempt at controlling the locomotive automatically. The basic idea is that it simply runs the train in one direction for 2 seconds, stops the locomotive, waits for a second, and then runs in the other direction for 2 seconds before repeating the process indefinitely; currently for some reason the locomotive travels faster and hence further in reverse than when going forwards, even though the power supplied is the same.

Given that this isn't a post on my code/electronics blog I'm not going to go into the full details here, but essentially I'm using an Arduino UNO with a L293DNE integrated circuit acting as a H-bridge to provide power to the tracks (the messy collection of wires to the left of the track). Power comes from standard transformer that provides 12V DC at 1.5A, and the speed of the locomotive is set by using pulse-width-modulation (PWM) to vary the duty cycle of the output (i.e. the percentage of the time the power is on versus off). This arrangement seems to work reasonably well, although I have found that the Kato chassis doesn't work as well as I'd hoped at low speed (even with a standard DC controller), although adding some weight to the body shell in the form of Liquid Gravity has helped a little. Interestingly if I put my N gauge locomotive onto the track it performs much better at slow speed. Does anyone have any hints on getting the best out of the Kato chassis (it's model number 11-104)?

Of course basing the change on direction on time is never going to be particularly accurate, especially given that the speed seems to change based on direction, so in practice I'll need some way of determining when the locomotive should stop and reverse direction. My current plan is to re-use some of the ideas from my scale speed trap to sense the presence of the loco at certain points on the layout and then react accordingly.

Another Brick In The Wall

Whilst the photo in today's post may look very similar to yesterday's (including the atrocious lighting conditions), it is in fact an entirely new wall.

While the construction of the wall in yesterday's post went well, I have to admit that I wasn't entirely convinced by the size of the stones portrayed. Given that the wall is a scale 4 feet six inches, that put each of the stone courses at over a foot in height, which seemed overkill for a small wall. I wasn't the only one who thought the stones were two large either (Paul mentioned it in the comments), so I thought I'd have another go.

I still wanted to stick with the same type of stone if I could, so that it would match the factory buildings I'm intending to build, so I simply printed the scalescens.com ashlar texture sheet at 50%, so now instead of three courses of stone there are six, and the wall looks a lot better.

The main remaining problem is that, as Paul also pointed out, the printed stonework looks very flat when viewed up close. While this probably won't be an issue for buildings at the back of the layout (even though the layout is very shallow), it could well be a problem for walls close to the front of the layout. I'm going to try and emboss the mortar lines to see if that helps, but it may turn out that I need to go the DAS clay route in order to add more depth. Of course there is no rush; I'm going to take my time and enjoy experimenting as I build the layout.

The Wall

While the final track plan and layout are still maturing slowly, I have decided that, in at least one place, the factory will be separated from its environs via a wall, and so I thought it worth doing a little experimentation.

Firstly, I'm sorry for the quality of the photo, but I wanted to blog now rather than wait until I could photograph under natural light, so you'll just have to put up with the grain. What you can see here is a short piece of wall that is four feet six inches in scale height; the courses total four feet, and the rounded capping stones are six inches tall. The figure is the driver from the Brian Madge kit that arrived the other day to give you a better idea about the scale. The height was set by the fact that I'm aiming for a wall that school children could look over to catch a glimpse of a steam engine, so I'm not aiming for a large curtain wall of any form.

The construction is fairly simple. I cut two pieces of 2mm thick cardboard which I then wrapped in a printout of the ashlar texture sheet from scalescenes.com. These two pieces were then glued back-to-back to produce a foot thick wall. The rounded capping stones were produced by wrapping the quoins section of the same sheet (the coping stones weren't large enough) around a length of 4mm half round Plastruct (part number 90885). The capping stones were then simply glued to the top of the wall. Simple but I think effective.

I might experiment with different types of stone/brick paper but I think the combination of 2mm card and 4mm half round seems to work well, so that's one more piece of the puzzle sorted.

Well Worth The Wait

Recently my modelling hasn't really produced anything interesting to blog about, mostly because I've been thinking rather than doing. I have two problems to solve before I can really start on building the narrow gauge layout I've been talking about since the beginning of the year; the track plan and how it will be powered/operated. Both of these issues have received some serious thought recently and I'm almost at the point where I'll be ready to share. I did think you all deserved some form of blog post though and helpfully today’s post was very obliging.

You may remember that at the beginning of the year I talked about the two narrow gauge locomotives I wanted to build for the layout. One of those was the small diesel locomotive which I recently finished painting, the other was a Quarry Hunslet steam locomotive that I wanted to build from a kit by Brian Madge. I ordered the kit at the end of December, and it finally arrived today.

Brian was very apologetic about the delay (a problem with the white metal castings apparently), but looking at the parts it was well worth the wait. This kit is, of course, orders of magnitude more complex than the kit from Narrow Planet that I just finished, so I'm going to take it very slowly; getting the valve gear right so that it runs freely is the part that worries me most. I can't wait to get cracking on it though, and fortunately I'm on annual leave next week so hopefully there will be some visible progress for me to blog about.

Distressing

So having assembled the Baguley-Drewry locomotive the next step was to paint it. My plan was to give it a well looked after finish, unfortunately that didn't happen.

The first step was to give it a coat of primer (Humbrol prime grey from an aerosol) which went on easily and didn't show up any areas that needed attention before the next layer of paint. According to the prototype information the loco would have originally been painted "hazard" yellow, with black side skirts and buffer blocks, so for want of any better ideas I'd picked up an aerosol can of Humbrol yellow gloss (I tend to prefer matt but gloss was all I could get). I masked off the side skirts and bufers and sprayed the model and left it to dry. This seemed to work well, and I had a wonderful smooth finish, so I then masked off the upper body so I could spray on the black paint (Humbrol again, this time black satin). Again this seemed to all go well, until I went to remove the masking tape.

When I removed the masking tape, not only did I find that in some places the black paint had run under the tape, but removing the tape had caused the yellow paint to bubble and lift. To say I was distressed was an understatement. My lovely smooth paint job was ruined. In fact I was so distressed that I couldn't bring myself to photograph the disaster before me. My initial plan to rescue the situation was to try and sand back the damaged areas and repaint, but I quickly decided that wasn't going to work well. I could have tried to strip the paint, but I didn't want to risk the metal parts coming loose. So in the end I decided to switch and finish the model in a run down and distressed state.

I used a combination of a small file, T-cut and a a blunted cocktail stick to remove the black paint that had leaked onto the upper body, as well as the badly bubbled yellow paint, and some areas that were actually okay but where I thought rust was likely to form. I then painted these areas using RailMatch dark rust. Once this had dried I then gently painted some water on to the rusted areas before sprinkling on some fine table salt. Once the water had dried the salt was well attached to the model. At this point I again masked off the black side skirts and buffers, before respraying the rest of the body yellow. This was then allowed to sit and dry thoroughly.

Once the yellow was dry I used a cocktail stick (the pointy end this time) to remove the salt grains which allowed the rust colour to show through, although in some places this also removed some of the the rust colour as well. Once all the salt was removed I dabbed small amounts of a rust weathering wash from Flory Models, onto the rusted areas, wiping most of it off with my finger in a downwards direction to simulate water having run across the surface -- I also brushed some of this wash across the black areas as well. The next step was then to use some of the Humbrol rust weathering powder (which was the free gift when I subscribed to one of the model railway magazines) to tone down the rest of the yellow paint so it didn't look like some areas where pristine while others were badly rusted. Final details, such as the window frames and door handles etc. were then picked out, and the makers name badge attached (with a drop of varnish rather than glue as it gives more time to position it accurately), before a light layer of satin varnish was applied to seal the paint to the model. Once the varnish was dry, the windows were glazed (in the same way as I glazed the windows of the lorry on Jerusalem), and then finally the windscreen wipers were fitted. It took me about 45 minutes to fit these, mostly as it took me about 30 minutes to find the one I dropped on the floor!

While this wasn't at all the way I had set out to paint the model, I am really happy with how it has turned out.

There are two things missing before it can be considered fully complete; couplings and a driver. The roof is only a push fit so once I find a driver model I can easily add one, and I'm not going to add couplings until I've decided on the track layout. The reason for this is that if I decided that the track plan is such that the loco will never run around a set of wagons, then I'll only need couplings at one end, at which point I wouldn't bother to fit both couplings, especially as I doubt they will improve the look of the model.

So while the process was distressing (in both senses of the word) I now have a model I'm really quite proud of.