MOK 8F 8425 – Lamp Irons Fitted and Tender top complete

Over the weekend in between checking over the Princess Firebox drawings, I fitted all the new lamp irons and I am happy that the upper tender is now complete.

MOK 8F Replacement Lamp Irons fitted
MOK 8F Replacement Lamp Irons fitted

I also straightened the middle lamp lower iron after seeing the photos

I also replaced the etched Irons that are built into the MOK etches for the storage of spare lamps on the tender front.

MOK 8F Etched lamp irons
MOK 8F Replacement Lamp Irons fitted

I really should have done a better job of rinsing away the Flash liquid residue as it has left tide marks.

MOK 8F 8425 – Remaining Lamp Irons Milled

Today I have made the final set of lamp irons for the 8F and thought I would share the method because it occurred to me that while I have used the mill the same result and basic method could be followed by someone with a file.

I started with some flat nickel bar 

Nickel Strip

I cut off four 40mm lengths and soldered them together.

4 Strips soldered together and Cleaned up

Once soldered together I milled all the edges flat. I needn’t have done the ends but with the mill it was a simple task. Here I have milled out the front of the iron.

Milling four irons at a time

Then I turned the block over and milled out the rear

Four irons milled but still attached to each other

This is the finished job before cutting off with a piercing saw and separating them.

Lamp Irons ready for finishing with a file

The finished individual lamp irons ready for final clean up with a file.

From the 40mm strips, I got eight lamp irons and I have enough material left already soldered together for a further eight which I will cut and put in the spares box.

David Andrews Princess – Firebox finished.

Finally the redraw of the firebox is complete. I ended up redrawing the lower section too because no surprise the existing one didn’t match the redrawn main firebox.

At the minute they are all separate bodies and I haven’t mirrored the lower firebox yet because I need to work my way through and check all the sizes before I combine the upper firebox into one body and the lower one into two bodies, left and right. It’s much easier to make alterations when they are separate.

David Andrews Princess Royal – Front lamp Irons

Needing a break from the metaphorical drawing board, I decided to make the lamp irons for the footplate.

I milled them from a length of brass bar. Initially I milled a length of angle and then cut slices off with a piercing saw. Then I soldered them edge on to the other end of the bar that I milled them from. Once soldered on, I milled the edges flat. I then turned them over soldered them on again and then milled them down to final size.

Milled Lamp Irons

They were then finished by hand with a file but I notice from the photos that some of the bases need deburring.

Milled Lamp Irons

MOK 8F GWR Double lam Irons – Milled from Solid.

Sep 15, 2017

Needing a bit of a break from re-drawing the Firebox for the Princess my thoughts turned to front lamp irons. As I was working out what was needed I got side tracked by working out how I might machine some of the double lamp irons that the GWR fitted to the 8F’s that they built

Milled Lamp Irons

Not the best photo as it’s a snip from a much larger photo found on the net to illustrate what I am talking about. The MOK kit does provide etches to make up this version of the lamp irons but I am not keen on etched lamp irons. I also thought that I would like to do them from nickel as the rest of the kit is nickel but I didn’t have any nickel bar thick enough. I do have some 5mm rod so my first step was to machine the end square in the mill.

Then it was a case of working out how best to mill out the bits in between the lamp irons.

I milled a groove down one corner of the square section and then rotated the part to carefully mill from the opposite corner to leave the two upright irons

Milled Lamp Irons
Milled Lamp Irons

the tops were then rounded with a file before cutting off the main piece. I could have transferred the work piece to the lathe and part it off but I just cut it with a piercing saw them popped it in the vice jaws and milled the bottom flat.

David Andrews Princess Royal – Replacement Firebox MKIV Work In Progress

I am still working away at it with not too far to go.

Over on Western Thunder someone questioned whether I was fitting mud hole covers. I didn’t add them to the original because they were not on the DA firebox casting, but having checked period photos they were fitted to 6026 during the timeframe that I am depicting so I had a go at adding them.

MOK 8F 8425 – Tender Buffer Heads

Back when I got this kit 12 or more years ago there were no buffer heads in with it. Apparently they were supplied by Ron Chaplin and he had just retired.
I really should have pestered Dave Shap for some replacements but time went on and it’s too late now. To get around it I imported the drawing into Fusion 360 and scaled it I then drew up the head to get dimensions and from there a happy few hours were spent turning some from some mild steel bar.

I wasn’t thinking when I picked up a 6ba screw/nut thinking it was 8ba. I drilled out the buffer castings to take 6ba before realising my mistake so I made the buffer heads to take a 6ba nut. Fortunately I found some suitable springs.

MOK 8F Replacement Turned Buffer Heads

They just need blackening now.

MOK 8F 8425 – Cast Works plates

Recent talk of printing works plates by guys on another forum got me thinking about the fact that I had managed to find an auction house image of the actual plate fitted to my loco which I downloaded. I managed to find it again today and shared it for comparison purposes only. 

When scaled and enlarged the font doesn’t match anything that I could find so I ended up drawing each letter/numeral individually.

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The images are much enlarged with the text and rim being only 0.2mm deep

MOK 8F – Replacment 3D Printed Tender Brake Blocks

Some time ago a fellow modeller who was building the same kit had some 3D printed brake shoes done. He very kindly sent me a set and they have been sat waiting patiently ever since.

While working on the other bits over Christmas I have been pondering the best way how to tackle fitting these. The brake hangers on Stanier tenders are curved so to replicate these my thoughts ranged from turning circular strips from sheet to bending strips from flat bar. In the end I gave my self a mental kick and thought why are you trying to ‘save’ the castings, you will never use them now that you have fitted 3D printed replacements.

So the next thought was right I need to remove the cast on, shoes from the hangers. Ian, the guy that had supplied the printed shoes also sent a note with some suggestions as to how to go about it. His first suggestion was to use the pips on the cast shoes as the location for drilling out the hole for the pin. I duly filed the pip down on one side of each casting until it was just a witness mark and then punched it. I used a pin vice to drill the first one and though sod this for a game. I drilled a hole in a lolly stick to take a 1mm drill bit (the same sized hole as the top of the hanger). I popped the leg of the hanger in the vice along with the bottom of the drill bit, which was inserted through the hanger and then the lolly stick. This held the casting firm enough to drill through it with my Proxxon mini pillar drill. The rest of the drilling was done in no time.

I tried the same set up to hold the casting to file off the bulk of the cast on shoe but using a file was hard work so my thoughts turned to milling them off. To use the mill I needed to hold them much more securely than a piece of lolly stick would allow. So I made a fixture from a piece of brass bar.

Fixture for holding brake castings while milling.

For the first side I just drilled a couple of holes at the appropriate spacing to hold the leg of the casting and the drill bit passed through the hole as before.

For the reverse side I didn’t have the leg to give me the secure holding so I milled a bit off cutting art way through the leg hole

Machining a Fixture for holding brake castings while milling.
Fixture for holding brake castings while milling.

Which gave me this.

Fixture for holding brake castings while milling.

Once both sides were milled I used a mini sanding drum in my Dremel to take off the last bit and restore the inner curve.

MOK 8F 3D Printed Brake shoes fitted

The last task was to insert some brass pins and superglue them in place while allowing the shoe to still pivot.

Next job is refitting them to the tender chassis as I had already fitted them some time ago.

David Andrews Princess Royal – Replacement Ashpan castings

I have been working away at the ashpan sections during odd half hours where it wasn’t worth getting into any physical modelling. I am almost there with it now, I just need to thicken up the top at bottom at the rear to make it match the DA castings.

The clamp on the bottom curve is very much a representation as I didn’t think anything finer would print successfully and if it did it would probably get knocked off during fitting.

MOK 8F – LMS 8425

Once I had sorted the errant part 146 and made the tender top fit I also fitted some rivets strips around the edge of the top plate that I had missed, moved on to adding the details to the tender front.

Brake and water scoop windlasses, water gauge and water scoop indicator rod. Plus another couple of levers whose role escapes me.

MOK 8F 8425 – Tender front details
MOK 8F 8425 – Tender front details
MOK 8F 8425 – Tender front details

The windlass handles were soldered to the cover castings using 295 degree solder and then the castings were soldered in place using 100 degree solder to make life easy.
The backs were tinned with the 100 degree, add a drop of flux, pop them in place and a small waft of heat from the micro flame and they were fixed. The water gauge was treated in the same way. a small blob of 100 degree solder applied to the pin pop in place then waft with the flame until the solder melts and the castings sits down in place. If it moves out of position it’s easy to reheat and adjust with tweezers.