More boiler parts

With the 3½" Mona out of the workshop I finally got around to making and finishing more boiler parts. 

Finishing the boilerplates

First of all, was cutting the plates to length. This was all done by hand: sawing and filing and sometimes the use of the angle grinder.

Firedoor ring

From a bar of copper, the firedoor ring was turned. This is a similar version as was made for the Württembergische T3, but only smaller. 

The conical shape (bigger towards the inside) gives a clearer view on the fire. 

Dome ring

Turned from bronze, this ring holds the inner dome to the boiler. 

Marking out the holes for the screwthread

Fly cutting the radius of the boiler shell. The ring is held by 4 M3 bolts to a steel mounting plate. This makes the setup in the vice easier. Only light cuts were taken. 

A separate copper ring is made, for making it easier to hold the dome ring in the correct position on the boiler shell while silver soldering. 

Chain drill the dome hole in the boiler shell.

With a half-round file, the hole is cut to size. 

The hole in the boiler is a about millimeter smaller than the dome ring, so that I can see during the soldering process, that the silver will nicely flow around the complete seam.

The copper ring will be held in position with a few rivets. 

Work in progress

Drilling the outer wrapper.

Making the holes for the safety valve bushes.

I didn't have a correct end mill size, so the boring head was put in action.

Drilling the holes for the steam valves. This loco has no turret, so several holes are needed.

Somebox tube plate

Locating the center of the tube plate, for drilling and reaming the fire tube holes.

The same procedure was used for the firebox tube plate.

An overview of the boiler to be.

Girders

On top of the firebox, for the backhead plate and smokebox tube plate girders are needed.

These were made with the shaping machine and the water spaces were done on the milling machine. 

The radius was cut by hand with a hacksaw and file. 

Finally turning all the bushes

Almost there to start soldering. Only two more plate girders are needed for the firebox. 

The drawing/design is progressing also. A start is made with the boiler fittings, dummy leaf springs for the loco and a first general outline of the reverser.

(To see this drawing full size, open it in a new tab, or download it.)

Mantenance of the milling machine

To continue with the boiler I first had to fix my milling machine. When running it made (especially at start-up) a strange noise, coming from a bearing or something alike. With inserting some extra oil in the vertical head, this could be overcome but it has got noisier over time. Something had to be done about this. 

Luckily a fellow model engineer Ramon knew how to do this job and how to dismantle the complete vertical head and gears. And this not a job I dear to undertake alone, so his help was very much welcomed. 

Removing the vertical head, with a simple support to take the weight. 

The suspected bearings are not visible, but are on top of the gear wheel

Disassembling the spindle. The main spindle itself however, is in a sealed cassette, which did not have to be opened. It can be taken out as one part. This is still ok, and has no standard bearings, but special needle bearings.

Extracting the old two bearings in one go, with a heavy bearing puller, that was specially bought for the job. 

Pressing the first new bearing on the gear, with a heavy press at school. 

We did replace the main bearings from the right-angle gear of the vertical spindle. Afterwards the complete assembly was mounted back on the machine. 

This gave some improvement, but not what we hoped for. The noise still persisted, deeper in the machine. The vertical slide, with its own gearing and transmission shafts, was probably the source.

So the next, more complicated, step was to disassemble this gear train that drives the vertical head. 

It quickly revealed that these bearings were not in a great condition and a lot of gummed-up oil and hardened residue was to be seen. After 45 years a replacement is necessary.

Unlocking the retaining screw, by holding the main gear in position.

Gentle tapping on the drive shaft from the back, it came out of the casting

The bearing that caused all the trouble and noise. It was very hard to rotate it by hand. 

The casting was completely cleaned out with petrol.

The old bearings that were removed. 

Everything assembled.  The job took two days and I was very glad that Ramon helped me. His knowledge and experience were desperately needed. He refurbished his own machine a few weeks earlier.

The milling machine with the new bearings. Nothing to be seen from the outside, but it transformed the noise levels of the machine considerably. An oil change of the oil in the gearbox was also done. 

The first job was opening out the chimney of the 'Simplex'.  This is a 5" gauge locomotive that my son is currently building. The casting was too big to hold in the chuck of his Myford lathe. Even for my lathe it was too big, but with an old large chuck on the rotary table, it was possible to mill out the internal diameter of the casting. This gave a reference surface for further machining in the lathe. 

The Simplex under construction, at the Intermodellbau Messe in Dortmund.