A Cracker locomotive

Gallery, Projects and General > Project Logs

<< < (15/21) > >>

lazylathe:
Very cool work as usual Arnold!!!

Will be following this build to the end!
Is the stoep track ready yet??

Andrew

DaveH:
Arnold,

Well you certainly took off this weekend, started with that nicely made tap, finished with an equally nice gas regulator. :thumbup: :clap:

A real pleasure as always Arnold – thanks :clap: :clap: :clap:
:beer:
DaveH

Rob.Wilson:
Nice going Arnold :bow: :bow: :bow: :bow: :bow:

Looks like you had a cracking couple of shifts in the shop :dremel: ,,,,,,,,,,,,, must be the warmer weather :lol: :lol: :lol:

Rob

arnoldb:
Thanks Andrew :beer: - the Stoep Track is laid and ready to use; just needs some final fixings and a bit of scenery... I left the track laying loose through the winter to see what happened at the rail joiners; I expected that the big temperature differences we get here (from 0C in the night to as high as 25C that same day) might wreak havoc with the track shrinking and expanding, and it did. So there's no way I can actually fix the track down; it'll have to stay loose to allow for the temperature expansions, so I'll most likely just dump some fine gravel down over it as ballast to limit movement while running trains.

:beer: Thanks Dave. Like I said, one of those golden shop sessions :ddb:

Rob, cheers mate :beer: - :lol: - We're back to high 20s and low 30s, so I've started to thaw a bit :lol: - Definitely nicer in the shop now :thumbup:

Today's little bit...

The gas tank body had to have a hole drilled through for the regulator body - so I clamped it up in the mill using the end caps to prevent the copper tube from collapsing, and a nice thick bit of cardboard to soak up the tiny differences in size between the caps and the pipe. Then I just plunged an 8mm end mill trough; no need to struggle with drill bits wandering all over the show:

On to a bit of silver soldering... I fluxed the bits where needed while assembling, and used a fire brick to hold things down. I set the job slightly over the edge of the bottom fire brick on purpose - using the broken indent on the brick to good effect. A small ring of silver solder was used around the filler bush right in the bottom; for the rest I decided to stick-feed the solder rather than use rings, as it would have been a complex job trying to make up rings for that lot:

I left the overhang at the bottom to use the fact that silver solder follows the flame's heat; as there was only a partial ring of solder around the bush, it would melt and follow the flame, thus coating and filling the entire joint. For the cap itself, and the regulator body, I used the flame around the outside and fed the silver solder in on the inside - also using the flame to draw solder into the joints. Around the regulator body, the solder flowed out nicely to the outside, as the brass bits sticking out into the flame got really nice and hot.

As I was in a bit of a hurry, I gave the workpiece just a very quick pickle, and used a scouring pad to clean up a ring on the inside where the bottom end cap needed to get soldered in. For the bottom cap, I used a ring of solder - bent so that it was a spring fit in the body, and that the cap would push it into the body when assembling:

Then I fluxed up the ring of solder, and around the outside of the end cap, assembled, turned upside down from the photo, and soldered the lot together. This was a bit more difficult; I couldn't see what the solder was doing and when it melted, so I had to keep a careful eye out for when the solder flowed trough to the outside - and then had to use the flame to make it follow around the joint.

Gas tank all assembled after more pickle and a bit of rubbing with Scotch-brite:

It's not pressure tested yet... I had to dig and scratch to find the recommended pressure to test it to; eventually I had a look at the different LP gas cylinders I have around, and nearly all of them was tested to 3000kpa (around 435psi). :palm: The highest-reading pressure gauge I have is only 1000kpa - so I'll have to invest in another pressure gauge; can only get that on Monday. Oh well, there's still many bits left to make, and then there's the little matter of a breath-powered Elmer's #46 Coomber Rotary that I have to make before middle October...

:beer:, Arnold

arnoldb:
Some more little bits out of the way... When an engine nears the running stage there's always a lot of tiny time-consuming bits to make :lol:

First up was the smokebox door handle. I went for a round one - just shaped a bit of brass by eye and threaded it to fit the threads I made in the smokebox door:

Then milled some 2mm cut-outs in it on the RT on the mill:

These were followed with a 2mm drill trough each cut-out.

Then I parted it off on the lathe; half-way down first, then used a small file to round the corners, then finished the parting. As I needed to work on the parted face a bit, I located one of those short bits of off-cut that never seems to be useful as it's too short to really use...:

I chucked the off-cut in the lathe and drilled and tapped it to match the handle-in-making:

Just screwed the handle into it for further work:

Then I hollowed out the front a bit with drills and used a riffler file to try and get a curve in there; not too successful, and not quite what I had in mind, but it'll do for now:

Next up, a bit of 4.7mm thick brass flat marked out and drilled 1.6mm through the width, two 1.6mm holes furthest away through the flat side, and a 2mm and 2.5mm hole respectively nearer in view through the flat side:

All the 1.6mm holes will be tapped 2mm.

A couple of cuts with a 0.5mm slitting saw:

And some tapping, 2mm clearance drill through one side of the top of each bit, and a bit of filing later, I had the bodies of the regulator handles:

Both needed, well, "handles" - so I fashioned some up in the lathe; just by eye; removing most of the material with the toolbits and using a small file to finish off the contours:

To the left, you can see that I used the file to nearly part off the handle; after this photo I just snapped it off by hand and filed the pointy left-over end down.

Then I had a look-see how things fit together so far:

:bang: The "Cab" is extremely busy, and everything is in something else's way... I Guess that's what happens when you don't follow plans strictly :lol:

I mulled things over a bit... I want both the steam and gas regulator controls easily accessible, and it must be easy to get to the gas filler valve for a refill; this loco will be run often, so ease-of-use and ease-of maintenance gets priority over aesthetics. I worked out that if I extended the steam regulator handle to the back of the engine, and turned the gas tank 90 degrees from the previous photo so that its regulator handle is at the side of the loco, all controls including the gas filler would be easy to reach, and the pipe work would be minimalist, making things easy to take apart for maintenance.

Extending the steam regulator left me two choices; I could make a complete new needle valve with a longer shaft, or make an extension piece. I'm lazy, so I opted for the extension piece :lol:
The easiest and cleanest-looking way to fit it to the existing is by using a steel pin through both; that can then be removed easily if needed, so I turned up the extension from some brass rod, stuck the valve in the end I drilled to fit it, and cross-drilled the lot for a 1mm pin:

A final check, and things look OK - the piping should be fairly easy to do now - both for gas and steam:

:beer:, Arnold

Navigation

 Message Index

Go to full version