Canopus: Pipework

With this post I'll have finally caught up with the current state of the build at which point updates may slow down as I move onto the more complex task of getting the thing to move under it's own power. So without further ado, let's talk about pipework.

You'd already seen one small piece of pipework when I added the balance pipe, but I've now added the injectors, the vacuum pipe for the break and the lubricators to the front of the saddle tank. Only the long pipe that provides the vacuum for the break is permanently fixed, the injectors and lubricators will be permanently fixed after painting, along with the handrails.

Strangely the instructions don't mention the pipe for the vacuum break, but not only is it clearly visible on photos and the works drawing, but there is a hole for it in the etched cab front, so I made it up from a simple piece of brass wire. The rest of the pipework are cast brass fittings. Unfortunately I managed to break one of the injectors when removing it from the fret.

I'm not sure how the injector pipe broke as I didn't exert that much force, but the long section snapped in the middle. I did try soldering it back together, but the joint looked horrid and didn't seem particularly strong. In the end I cut of the broken sections, drilled holes in the two end parts and then fabricated a new pipe from brass wire. This was then slotted into the drilled holes along with some solder paint. A quick touch with the soldering iron and I had a repaired injector, which looks the part.

You may also notice that I've moved on from using a piece of wire insulation to hold the coupling rods on. Now each rod is properly attached to all three fly-cranks with a small nut. These are amazingly tiny and very fiddly to fit, especially as the bolts are cast so not a perfect screw thread. They will eventually need fixing permanently and then the remaining screw cutting off and the bolt filing thinner but that will wait until I've got the motor in so I can check the movement is nice and smooth and make any necessary tweaks.

Canopus: Joined Up Motion

List time you saw the chassis for Canopus I'd fitted the wheels and the cylinder bracket to complete the basic rolling chassis. Since then I've added the fly-cranks and coupling rods to both sides (so the wheel quartering is done). I was a little worried about doing this but as you can see the chassis is still rolling nicely and looks great with the body rested on top.

The next stage is to build the gearbox. Unfortunately this may take a while as I've discovered that the supplied parts won't build into a working gearbox. Since the kit was originally designed some of the parts have been replaced, and this includes the gears. Unfortunately the change in gears means that they will no longer stay in the correct position within the gearbox so I'll need to figure out a sensible way to proceed. I have some ideas, but I'll need to get some more supplies from my local model shop before I know if I have a working solution.

Canopus: Balance Pipe

Now I'm not quite sure what a balance pipe is for, especially on a locomotive with, as far as I know, a single water tank, but it is worth noting that the dimples marking where it should fit on the saddletank casting are in the wrong place. All the drawings and photos I've seen of Canopus show the pipe curling tightly under the boiler just to the front of the tank filler cap. If, however, you look at the saddletank casting the dimples are positioned just to the rear of the filler cap.

Fortunately this is easy to fix by simply drilling holes into the casting in the right place and using a little filler to cover the old dimples (and the first hole I started to drill in the wrong place). Once the saddletank is glued to the boiler fitting the balance pipe (just a bit of 0.8mm wire formed around the handle of my modelling knife) is nice and easy.

Now if you remember I hate fitting handrail knobs to the saddletank. Having eventually got them right, I've had to do them again, as I've discovered that the saddletank casting appears to be slightly twisted. I glued it into position and checked that it looked level from the front (i.e. the bottom of both sides were level) and that the tank filler cap was in line with the chimney etc. It was only once the glue had set solid that I discovered that at the cab end it isn't so level, which of course meant that the handrails weren't level. I did try to break the glue to re-position the tank but it isn't coming off, so I've tweaked the handrail holes slightly to try and get them level back to front and at the same height on each side. They aren't perfect but for normal viewing they will be fine; it will only be a close up inspection from directly in front where you might notice a problem.

Canopus: Reversing Gear

So the next detail added to the body was the reversing gear. Annoyingly I didn't think to take a photograph of the part before I'd fixed it in place so it is now a bit difficult to see how it goes together. This was quite a fiddly part to make as there are three etched parts and some brass wire to be soldered together.

The reversing lever is made of three etched parts; the main lever and the rod the protrudes through the cab wall, and then two toothed gear racks. The three parts are held together by two small pieces of wire that slot through all three parts at both ends of the toothed racks. As I'm sure you can imagine holding all this together is a bit tricky, but worth it as the result is a very fine representation, such a shame really that once the model is finished you'll almost never see it; another good reason for keeping the roof removable.

Canopus: Freewheeling Chassis

So having started the day with a post on another body detail I thought I'd focus on the chassis for Canopus in today's second post. The last time you saw the chassis I'd added all the overlay detail but had yet fitted the wheels and soldered it solid. Well I've now added the wheels (including the insulating washers) and soldered on the cylinder bracket and the front cross-member to complete the basic rolling chassis. Rather than a photo I thought I'd show that the chassis runs nice and smoothly even without the extra weight of the body.

While I'm happy with how well it moves now, I'm hopping it still moves that freely once I've fitted the fly-cranks and coupling rods. I'm a little worried about fitting the fly-cranks as I've just realised why reaming out the axle holes was such an involved process.

The instructions mention that the fly-cranks should be an interference fit on the 1.5mm axles. I had a quick look to see how well they would fit only to find that they don't... at all. A little bit of measuring and I've discovered that the supplied wheels (which a packing note explained differ from those in the instructions) are actually on 2mm axles. Clearly the bearings that were supplied fit the axles, but the chassis etch obviously hadn't been updated so rather than just a small amount of reaming to get a push fit, I had to remove 0.5mm of extra material. On the chassis and axleboxes this wasn't a problem (other than being time consuming), but I'm a little worried that once I've removed the extra material from the fly-cranks that they might be a bit fragile.

Canopus: Handrails

I'm sure most modellers have something that they find difficult or hate doing. So far, my pet hate is handrails. I had real problems getting them right on the Quarry Hunslet loco and fitting them to Canopus hasn't been much easier.

Initially I thought they would be fairly easy to do this time as the saddletank casting had six small dimples in the right places for the handrail knobs. All I would need to do was to drill the holes at an appropriate angle. Having struggled with this before I knocked up a holder, inspired by Paul using a V block, from a small mitre box and some cardboard and then set about drilling the holes.

Annoyingly having drilled the holes on one side I found that while the two end holes were fine the middle one was well out of position. Rather than trying to fill the hole and drill a second one, I decided to just stick with two handrail knobs on each side of the saddletank. Strangely while the kit suggests three per side, and a works drawing Paul sent me also shows three per side, every photo I've seen only shows two, so I'm happy with just two.

Once I'd drilled the holes and checked the alignment I gently tapped the wire to the saddletank and then used a small drop of solder paint to fix the knobs to the wire. I've now reduced the wire to the correct length and tided up the solder, but I haven't fixed them in place as it will be easier to paint the body and then fix the rails in place, so for now they are neatly labelled (which side and which way around) and stored in the box with the remaining parts.

In theory Canopus should also have a curved handrail attached to the front of the tank that wraps around the chimney but I wasn't convinced that it looked great so I've filled the holes and will leave it off. As I'm not intending to create an accurate copy of Canopus I'd prefer to like how it looks and not add a part just for the sake of doing so.

You can also see from the photo that I've glued the filler cap to the top of the tank which I think completes the fittings I can add before I glue the tank to the boiler.

Canopus: Cab Roof

I know I've already blogged today, but I've now got quite a few detailed bits of Canopus to blog about so I thought I'd do a second post today to try and catch up. The last time you saw the body I'd fitted the boiler and smokebox (the saddletank casting was just rested on) but the cab was still roofless. The roof itself is a single etched part that needed gentle shaping to match the profile of the cab. Once correctly shaped two small etched parts were soldered on to represent a ventilator and a flange around where the whistle and safety valves will protrude.

While the roof looked good just rested in position, it obviously needed a more sensible way of keeping it in place. Now I could have soldered it to the top of the cab sides but that would leave it difficult to access the cab for painting etc. so I took a different approach (which is also suggested in the instructions). I picked up a short length of 2mm x 2mm brass angle from my local model shop and cut two short pieces to be a tight fit to the cab sides. I then used masking tape to fix these in position along the top of the cab sides, before taping the roof into the correct position. I then flipped the body upside down and tack soldered the two parts to the roof and then removed the whole contraption and added some more solder to make sure the joins were solid. The brass angle encroached a little too far down the cab sides and so was visible at the top of the door opening, so I simply filed this section away while holding the roof in place and so now from normal viewing angles you can't see the brass angle at all.

The roof is now a nice push fit to the cab and will even stay in place if turned upside down, while still being easy to remove.