Rob Pulham

Me neither, and that's embarrassingly from someone who has several sets of Slater plastic brake shoes in unmade kits and some 3D printed examples in a couple of others....

I wasn't really happy with how far away from the wheels the brake shoes needed to be to ensure that they didn't short. I rew up some brake shoes in Fusion and a friend kindly printed them off for me. Today I had the chance to test fit one of them. After checking that I hadn't messed up and that the etched hanger would go between the flanges. I bit the bullet, unsoldered the etched overlay and cut of the brake shoe from the hanger. The next question was how to attach the printed brake shoes to the hangers. I hoped to have the shoes free to move and after considering and discounting various options which involved superglue I settled on a dressmakers pin and short length of microbore tube soldered to the pin and then filed down.

Ahh, got you. No need to say anymore...

Thanks George, I have done a few DJH kits before without valve gear issues but not a Fairburn. Or rather the only issue I had, was one of my own making where a drill bit broke in a valve guide casting. What's the problem?

With the slide bars in place at the cylinder end it was time to start thinking about the outside motion. I decided to do it as two subassemblies and then join them together as I secure the rear end of the slide bars to the motion bracket. Along with the Premier Components coupling rods, came a set of the rest of the motion parts many of them very nice but some just didn’t work (or at least in my view). These are the combination levers and the union links. Starting with the combination levers, those fitted to the Princess Royals were fluted and the Premier examples plain. The union links in the Premier set are represented by a single dog bone shaped rod which is 0.9mm thick. The very visible, prototype union links have forked ends. After exploring options of combining the etches with the premier link I realised that they were each of different lengths so no chance of combining the two. After consultation with the gent that I am building it for, I went with the DA etched combination levers and union links but used the Premier parts for the rest of the motion. For me the most difficult bit of building motion, inside or out is “how do I fasten it all together”. For the front half I have tapped the valve rod 14ba and put a screw through from the inside. Visible in the photo below. The union links I have riveted with 0.8mm brass rod. I have a small piece of steel that I use as an anvil so I drilled a shallow depression in one corner to use to form rivet heads. Once inserted I peined them over with a small ball pein hammer. I also turned up some oil pots for the connecting rods. Not quite prototypical but they do look nice. While I am using the Premier Rods, I still need to use the DA etched expansion link and that’s where I was second guessing myself On all the other outside Walschaerts valve gear that I have built before, the radius rod is connected via a pivot below the main pivot of the expansion link. I thought I had assembled it wrong but after searching through a number of photos and reviewing the outside motion GA for 6203-62012 on page 38 of the Wild Swann book. It seems that on the Princess Royal there is no lower pivot point. Phew! Finally, I was pondering the brass bearing cap on the eccentric rod where it attaches to the return crank. There are some etched covers included but since the whole kit is etched nickel, they are nickel not brass. So, I had a quick go at mocking one up on the lathe. Although it doesn’t have the small screw heads and the oil pot it does look more three dimensional than the etch and of course it’s brass. I will sleep on it and see where I decide to go next with that one.

Back to the Princess this week after moving the J6 along. In the end I decided to take a bit more of the edges of the cylinders and then I fitted the covers. Before I did that I soldered the slide bars in place as I didn't want the heat from soldering them in place to spring the cylinder covers loose. As it happens I had to adjust one of the slide bars as I hadn't got it quite square and the cylinder covers are such a good fit that although the solder softened, they never moved. Something to aim for on future builds. After fitting the slide bars I mated them up with the motion bracket and realised that once I join the two together them crossheads become captive so I need to do work on the motion next to ensure that all is well before I solder the slide bars to the motion bracket. The first hiccup is a result of using extras to the kit. I used the David Andrews Slide bars and crossheads for the simulated inside motion because they don't have as much details as the LG Miniatures versions. Now I come to fit the LG crossheads with the connecting rods which are replacements from Premier Components I find that the LG crossheads are different to those that I have used on other builds in so much as they have a slot in them rather than an open back. This means that I will have to mill the connecting rod ends to get them to fit in the slot. A picture paints a thousand words or something like that...

Thanks Chas, The answer to your question is with a lot of trial and error. They will definitely need adjusting, or at least the front pair will. Having got everything else together now, I think that I will need to add slightly longer pull rods between the front and middle pairs.

A couple of weekends ago I was demonstrating Loco building at the Stainmore Railway Model Railway show. I took along the chassis for the J6 and had it running on the rolling road all weekend. Besides giving the motion a really good bed in it attracted a lot of attention. So much so that I plan to make up another chassis with inside motion for my demo stand. On the back of a great weekend out I decided to see if I could crack the construction elements of the J6 last week. The remaining jobs were. Fit glazing Add Milliput to the back of the balance weights to make them solid rather than just an etched front. Fit the sand pipes Fit the remaining linkages between the brake pull rods and the brake cylinders Fit some Frame extensions under the boiler between the front pairs of wheels to hide the rear of the wheels – following Tony Geary’s lead. Balance weights, I added a coat of primer to bled it all in before final paint and weathering. The first bit of the brake linkages Front sandpipes and Frame extensions. Before fully soldering them in I tested the frame extensions at one side by tacking them in and the seemed perfect. But the chassis mustn’t have sat down properly because I noted while testing for clearance on the rear sandpipes that they need trimming down a bit. Rear sandpipes. I had to fit the tops of them very close to the frames to avoid the injector pipework but I got there after two or three adjustments. Last but not least a couple of shot of the remaining brake linkages. Although soldered at the rear the ends of the rods are a loose fit in the turnbuckles so allowing removal of the brakes.

Nick Dunhill is a member of the Gauge O Guild Technical committee. He was formerly a research scientist, a gardener, a vegetarian café owner and now builds model locos for a living. It was a long apprenticeship but eventually he realised he could make a better living, building locomotives rather than cooking vegetarian food. Nick continues his series of presentations on scratch building a locomotive and this time he shows us how to build a footplate. This follows the boiler, smokebox and firebox demonstrations in earlier shows and videos of these sessions can still be found on the Gauge O Guild YouTube channel, just search Nick Dunhill. Please note that you do not need a YouTube account to view any videos. As usual it is at 20:00 BST. The date is Tuesday 26th July 2022. Members can attend for free and Non members pay £2:00

I have already replied once but lost it when I my broadband dropped out. Putting it all in aa word document in a labelled folder is my usual way of storing such info and backups are second nature after working in IT support for 20 years. The Clayton is unbuilt or actually the motor bogie is built and was so when I bought it. but the body including the trailer are untouched. What I can't recall is whether the motion has been assembled or not. I will have to look. I bought it from a very good builder and fellow Gauge O Guild member who is based in Germany so I was confident that the motor bogie would be fine. Indeed I broke off typing to have a look and both bogies are assembled and the motor bogie ran straight out of the box after sitting there for four or five years since I bought it.

This is really very useful Chas, I haven't yet got my hands on a 7mm Sentinel railcar but I do have a Clayton complete with trailer. I just need to remember all this research when I get to building it. The good news is that I have all the books mentioned so that's a good start.

That is superb Chaz, a real credit to you. Something you will enjoy looking at for a long time to come.

It's alive at long last. I fitted the final parts of the motion, and the motor and gave it a test run. Thankfully it ran straight off without any issues with the motion itself but the chassis had an odd wobble on the rolling road when running forward that wasn't evident when running in reverse. Initially I wasn't concerned, because running on my rolling road is never as smooth as it is on track. But then I noticed that the middle driver had a pronounced wobble and thought that the screw had worked loose. When I lifted if off the rolling road and felt the wheel, it felt loose but when I tried to tighten the screw it barely moved and the wheel was still loose. This was a bit dismaying because this is the axle that I have spilt for the motion. My first test was to swap the two centre wheels over to see if I had the same issue and much to my relief, both tightened up as they should and the wobble went away.

In November 2021, Jeff Langham and Peter Reynolds talked about signalling on the real railway and how to apply it to your model railways. This latest session will take that a step further and show you how they get their signals to work. A convincing model railway, of any size and of any era, just cries out for working signals. This is considerably easier in 7mm scale than in the smaller scales to achieve. As members of the SR7mm Group Jeff and Peter will share their experience. If you missed the first session you can watch it on YouTube. The event takes place on Sunday 26th June @ 20:00 BST You must register for this event as places are limited. The event is FREE to members or £2:00 for non-members.

Following a question about parts for the inside motion on the Guild forum, a fellow member posted how he had achieved a similar result to what I am working on but without the use of a lathe. I must off thanks to Harold because his post gave me the solution to one problem that I had been pondering (how to space them apart for soldering) and for prompting me to think that I didn’t actually need to solder them to the axle at all. I could solder them to the bush which acts as a spacer and would allow a hole to be drilled to make use of the taper pin that holds the axle together. In true Blue Peter style, here’s two I made last night before I got my head into gear and correctly worked out the width. They will go in the spares box as I am sure that they will come in for something.

Today I made up some connecting rods for the inside motion. They came from the scrap etch box and were originally for a Black 5. I cut off the big end bosses from all the pieces and then soldered them together in pairs. Once I had measured the length, I cut them to final size and grafted some Laurie Griffin eccentric straps onto them. I have calculated that the home turned eccentrics will give about 3mm of travel fore and aft but that will be sufficient to give the sense of movement though the holes in the frames.

Hi Chaz, No bloom at all, it's resin based and I would liken it more to the pva end of the spectrum that cyano but it certainly sticks etch to both cast metal spokes and 'plastic'* spokes - I added the balance weights to the J6 yesterday after my successful test on these the day before. * I say 'plastic' but it's really whatever Slaters wheel centres are made of and I am not sure that 'plastic' fully covers it.

Tuesdays have become quite a busy day in the Pulham household so I didn’t have too much time at the bench. One of the jobs that I always seem to forget until the last minute when building are the balance weights. I normally wouldn’t have taken photos of such a simple thing but in this case, I wanted to share the type of adhesive that I used. After reading about it on Western Thunder as being specifically designed for etched metal and clear parts, I thought that I would give it a go and bought some. I am not a great lover of cyanoacrylate type glues, not because of their adhesive properties but because the fumes can leave unwanted residue especially on paintwork etc. which is difficult to get rid of. The glue needs 6 hours to fully harden and to be honest it doesn’t seem to have great “grab” when initially applied. But being able to wipe off any overspill with a damp cotton bud and no residue from fumes is a big plus, assuming that it works. Well, my scepticism was unfounded, the balance weights were nicely stuck when I checked them this morning. I also added the inner plates for the weights cut from some 10thou nickel sheet.

My appologies Chaz, I didn't actually look at the instructions only the photos. Having had a look at the instructions you do get Crossheads and slide bars so that's a bonus. Much cheaper than 7mm. A full inside motion set is over £100 these days.

Just a reminder that The Guild's Summer show is on next Saturday at Doncaster Dome - see above for full details.

Thanks Chaz, Once it all fits and starts to move as it should it's very satisfying. I was talking to a friend a few weeks ago who has been putting inside motion in locos for years. He said that once you have done it once, building a loco without inside motion will seem very strange and the frames will feel empty. Having done it now, I rather think that he's right. I have actually collected a few inside motion sets so I will be able to do it in at least some of my future builds. Brassmasters still do an inside motion set. I bought one to put in a 4mm LMS 4F but when I moved to 7mm I sold it before I to around to attempting to fit it. You can find it here The downside is that it only seems to be the eccentrics it doesn't have any cranks, crossheads or slidebars.

I know what you mean about the procrastination Chaz. It's very easy to build things up out of all proportion so that when you actually pluck up the courage and get on with it, they don't seem half as daunting as they did in your head. You must be really pleased with progress so far, it looks superb.

A bit of a milestone was reached in the Pulham household last night. I have been tinkering for a number of days with the inside motion, getting it all to fit in the frames. I had to mill the inner side of each crosshead to clear the eccentric straps etc. so they are now handed and I also had to enlarge the centre section of the motion bracket to allow the assembled eccentric rods, expansion links etc to pass through it. Then came the final job of determining the length of the connecting rods and cutting them to length. Once they were cut and tried in place the length was right but they wouldn't fully rotate because I hadn't made the slots in the motion bracket deep enough. Much filing and testing ensued but I didn't seem to be getting anywhere and then I realised that because of the constant assembly/disassembly for testing, I had the frames upside down. What I was viewing as the top was in fact the bottom so I had been adjusting the wrong side. More filing and test ensued and I got there in the end. https://youtu.be/dK2cuyRbb9w Having tested the pistons successfully with the valve parts resting outside the motion bracket I put it all together inside for a further test. https://youtu.be/njuSUQVBkjc

Although I bought my collet Chuck from Arc Euro to suit my lathe (SiegSC3), I had bought my collets (ER25) previously via eBay for the previous lathe and haven't had any issues with them. Although I let the collet chuck for the Unimat go, when I sold it. I kept the collets as I also use them on my mill. Pretty much all such things are produced in China or India these days anyway, no matter who you ultimately buy them from.

Thanks Tony, I am thoroughly enjoying it, I do like the flowing lines of the former Great Northern Locos. I have a few more in the pipeline.