Although I still need to finish of the chassis, the body and tender are pretty much complete, so I took the opportunity to return to this build and pipe up the injectors, and fit the vacuum pipe down the right hand side valence.
I had drilled the holes for the pipes and cut lengths of copper wire some time ago, then they were put aside.
The vacuum pipe was surprisingly difficult to photograph with it being so long.
The extras included with the kit include some very nice LG Miniatures castings for the rear valve guides. The only issue was positively locating them due to the nature of how they have been cast there is a very thin spigot to fit in quite a bit etched hole.
My answer was to turn up a couple of locating bushes.
There are only two I just combined two small photos to show the detail.
This made them easy to locate into place.
There will be a short break now while I prepare for our first demo session for two years. Anyone planning on attending Newton Aycliffe Model Railway Show on the 26th do drop by and say hello.
As is usually the way in life, when making up the valve guides above I search for a photo that showed them in detail but couldn’t make out anything in the gloom from the footplate. Or ones that might have showed enough detail went pixelated when enlarged.
Paul Hannah kindly posted a snip from a photo that did show enough detail over o Western Thunder to make things out and politely suggested that I had the bolts a bit overscale. Having looked at the photo I had to agree so off they came.
Another productive session this afternoon saw the parts above detailed ready to fit. Although I have the Milling machine and a rotary table for it, I kept my Proxxon mini Pillar drill and dividing head which I use for drilling out the small stuff.This is the set up when I lift it onto the bench.
This is partway through drilling out the valve guides
Once drilled I did my usual trick of wire and microbore tube filed to a hex for the head. I also fitted the rather nice brass cylinder relief valves that came with the kit.
Thanks Andy, This week has mainly been more lathe work. After a suggestion elsewhere I remade the two front crank pin bearings in steel and then because I had worked out a technique to make them much finer I remade bearings for the other wheels as well. Hopefully my first efforts will coming somewhere for something.
With those done to my satisfaction I turned back to the chassis and the cylinders/motion brackets. More on the latter in another post but first the cylinders. I used the David Andrews Slidebar/cross heads for the inside motion and the LG Miniatures pair that I will use for the outside don’t come with the cylinder back plate. Timing being perfect, just this week I acquired some assorted thickness Nickel Silver bar ends. They weren’t cheap overall, but worked out at about half the price that I would pay from my regular supplier, whose prices I am happy with..
Then I turned (if you will pardon the pun) to the fronts of the cylinders. The castings with the kit are nicely detailed but sadly both the cover plates and valve guides are oval, presumably as a result of shrinkage in the casting process.
They still need a few more details adding before I solder them to the cylinders fronts but I am happy with them so far. There is a gent, whom I have met a couple of times. Who posts superb builds over on RM Web under the username of Jazz. His tag line in his signature is, “Learning by doing” and I couldn’t agree more with the statement. I have learned a great deal this week while twiddling the knobs on my lathe…
Now that I have a proof of concept on the front crank pins, I returned to the brake linkages.
The linkage that connects the cylinder with the brake pull rods is supplied as a pair of etches that are laminated together. – Parts AA/AB in the diagram below.
I decided to see what I could come up with as an 3D compromise. So I butchered the etches and then laminated them together with some additional parts turned/milled from rod.
Which gave me these:
Next, I added strips of nickel to the two etches which support the brake linkages behind the brake cylinder.
I did need to cut one of them to accommodate the motor, but I preferred to cut it after I had made them up. You can see that there is a half-etched cut line to allow for this.
Next, I went to fit them and that’s where life got interesting again. If I soldered them into the slots in the horizontal plate as intended, I lost access to the screws which hold the rear springs on. I am pretty sure that during the course of fitting the motor and get it running, that I will no doubt need to remove the rear springs at some point.
My solution was to make a small plate from scrap etch which could be soldered in between the two frames and then drilled for a 10ba screw. I had to make a little jig from the 10 BA screw and a piece of spare rod and some washers to space the top part of the frames the right width to allow me to solder the plate in at the bottom. I made it slightly trickier for myself by electing to make it precise enough that the frames still located in the slots. Soldering the base plate on took a couple of attempts before I was happy that it sat correctly.
Then it was a fairly simple matter to drill 10BA clearance (1.8mm) and solder a nut on the frame. This allows for the screw to screw in from the top of the chassis on the basis that it’s less likely to drop out in motion that way.
As an aside I was really surprised that the stub on the base of the brake cylinder was a really snug push fit in the hole snapping into place when I pushed it home. I was surprised because I hadn’t thought to measure the hole prior to assembly of the frames and measuring it accurately was quite difficult with the tools I have.
In the view from the top of the frames above you can see the screw and the tabs of the frames located in the slots tightening the screw makes them snap into place quite easily.
Steeping back slightly, I was asked by a fellow GOG member on the forum how I planned to tackle the front crank pin ‘nut’. Initially I hadn’t a clue how I was going to do it other than probably reversing a crankpin bush. As I was pondering on how to reply to the enquiry I had the germ of an idea.
I had a go at a proof of concept this morning after my lightbulb moment when replying last night.
This is what we are looking for (just in case you needed a reminder)
This was my first attempt, I think that there was a slight bend in my bit of spare 8ba stud as it didn’t machine each face evenly and the nut/stud portion was far too big
After a coffee break I reversed the short length of stud and had another go.
After the vacuum cylinder, I started to look at the brakes. The crossbeams came with brass castings for the clevises that fit around the etched pull rods.
However amongst the bags of extras were some really nice Hobbyhorse castings for clevises designed to take round rod rather than the flat etches. I made some adjuster nuts to enhance the rods and fitted them to one end. I will fit the the other end once I know exactly how long the pull rods need to be.
Next job is to drill out the Castings for the brake hangers/shoes.
While I was at the lathe I decided to make a replacement vacuum cylinder. The casting supplied was actually one of the better castings but it was not quite the right shape and undernourished when compared to the drawing.
So a fun time was had turning a new one an dressing it with studs/nuts. Those who are paying attention will note the odd arrangement of studs which I took from the drawing. I had an interesting time working out all the different angles four at 45 degrees and the other three at 56.25 degrees from those.