Atomiser for an LNER A3

Amongst the minor casualties of the strip and repaint of my DJH A3 that I am aware of is the atomiser casting that sits on the side of the smoke box. Now I could have bought a casting from Ragstone or Finney7 but where’s the fun in that. And so, I set out to make one using the mill and lathe.

In the absence of having any collet blocks (subsequently ordered and received) I used a pin vice with a hex head to index milling the flats on the bar to create accurate hex nuts. I used a toolmakers clamp fastened to the rear jaw of the vice as a stop so that I got the pin vice back in exactly the same position as I rotated it after each cut.

Using a hex head pin vice for indexing on the mill
Using a hex head pin vice for indexing on the mill

I had a first attempt which came out alright but I felt it was a bit small. I dug out a casting from my Finney A3 kit and it was certainly longer than the one that I had created.

Atomiser For LNER A3
Atomiser For LNER A3

Learning all the while, I thought that I would have another go.

Atomiser For LNER A3
Atomiser For LNER A3

Setting the Unimat on its fastest speed, I found that I could not only successfully turn down the spigot for the handwheel, I could also grip that spigot in a 1mm collet and turn the head down to size with light cuts and a sharp tool.

I was concerned that the spigot being turned down to 0.8mm wouldn’t have enough strength and that the turning forces would cause the head to shear off. I proved it wasn’t a fluke by doing a second aft inadvertently crushing my first attempt when I didn’t get it sat square in the collet.