David Andrews Princess Royal - 6206 Princess Marie Louise

Having made the error on the oilboxes I share your pain.

 

This weekend has been about working out how to fix the firebox and boiler together and to the footplate. I put a couple of 12ba screws through the bottom of the firebox utilising the two holes etched in the footplate. The ultimate intention is to use adhesive but also to use the hole to dd a mechanical element to the fixing so the screws are temporary to allow me to get everything in place. I would also like to get all the soldering done around where the firebox and the lower sections will sit since resin is susceptible to heat damage if I am not careful. Picking up a tip from John Dale I elected to screw the front end of the boiler in place and I was rather reluctant to use just a nut on an internal curve as I didn't want it to come adrift sometime in the future. A rummage in my useful bits of brass recycling box yielded a former frame spacer from a set of frames that I had replaced with new ones. As a bonus it was already tapped 8BA. I filed the ends to help it seat in the curve and after marking and drilling a hole in the front saddle casting and transferring that through to the bottom of the smokebox I soldered it in.



A dry fit of the boiler and firebox and all of a sudden it starts to look like a loco.

 

The next bit of the puzzle before permanently fitting the firebox, is the vacuum ejector pipe running from the casting at the firebox to the smokebox pipe elbow fitted some time ago. Making up the pipe was relatively easy, make up the bends and kee trimming the ends until it fit in the right place.



The ejector pipe is retained by four pipe clips. In the kit these are provided by 1.5mm wide etched strips.



However upon checking photos these retaining clips were not flat but rounded like a big handrail knob. A couple of years ago when a friend passed away I inherited a box of 1 metre x 1.5mm brass brazing rods. I cut five lengths and soldered them to a piece of thick brass to hold them while I worked on them.



I then milled off 0.75mm leaving them as half round pieces.




These I removed from the block and scraped off most of the solder. I annealed them and then bent them round a length of the 1.5mm brass rod to form what are effectively brass split pins.



Finally I cut them to length. They look much bigger than they are in the photos


Next up is drilling the boiler and firebox to accept them.

 

Still working on the body details, I next approached the Injector pipe that runs along under the footplate on the right hand firebox side.
This is the casting supplied.


For Christmas, I received a new four jaw chuck for the lathe and wanted to give it a try so I decided to make the jointing flanges first. I had a length of brass bar which was the right outer size without further machining so I centred it and drilled it 3mm. Just to be sure I also ran a 3mm end mill through it. Finally parting it off to length


I turned a 3mm spigot on the end of a piece of rod from the useful bits box and fitting the workpiece to it I mounted it in the dividing head and used the stub of a cheap carbide drill that I had reground after it broke off to spot drill each corner. These cheap Japanese carbide drills are very good but incredibly brittle even the act of bringing them down to the workpiece can break them off, if you are slightly heavy handed.



Then I drilled them 0.7mm and fitted wire and tube hex nuts to complete the part.





Next I turned a small top hat flange for the other end and then bent the pipe to shape before finally adding retaining straps from scrap etch strips and more 0.7mm wire





Onto the next...

 

I just can't help myself...

 

That's interesting, there was only the one bigger sized pipe included in this kit. There is a casting for the smaller pipe flange, but only one of them. I am just in the process of making a pair of them.

 

In the end up I wasn't happy with the first pair of smaller pipe flanges because I hadn't managed to get the centre hole in the middle. The cross section of the bar that I used was too small for the 4 jaw so I put it in a collet to drill the centre hole.

However I made the mistake of leaving it full length rather than cutting of a short length and I think that the length of the bar, not being properly supported by the round collet was pulled out of square by the length of the bar. So I milled a stub of round bar into a square and remade them. In the end I made five and chose the best three for the pipework.

Working out the pipe runs required study of the GA and reference to photos but I think that I have it now.



Other than the fitting of the handrails I think that these might be the last parts to make for the upper body/footplate but I will double check to be sure.

 

Of course sod's law dictates that I had just nicely finished assembling these when I found a second casting on another sprue that was identical to the first.

I guess that I must have picked up both sprues separately at different times, thinking that they were both the same sprue...