Chimney and smokebox for ‘Sweet William’

[ken king, King DesignParticipant @kenkingkingdesign]

Assembling chimney components and making smokebox door hinges

[ken king, King DesignParticipant @kenkingkingdesign]

Some more work on my client's 'Sweet William' saddle tank locomotive, starting with the chimney. It comprises three parts, a nicely turned and finished brass top casting, A length of standard copper pipe for the stack, and an unfinished bottom casting.

After squaring the pipe end the top was soon silver soldered in place and the pipe cut to finished length. The bottom casting arrived roughly bored through but externally was as cast.

It was carefully set up in the four jaw chuck and the bore was cleaned out to fit the pipe, making sure it all ran true, then as much as possible of the outside was skimmed. this wasn't much because the section quickly changes from circular to something else !

The rest of the outside needed much heavy filing but eventually yielded a fair surface.

The underside needed dressing as well, and this was done by wrapping coarse wet & dry paper over the smokebox and sliding the casting around the curve … for a considerable time. I wanted to achieve a dressed surface to contact the smokebox all around the perimeter and pretty much got there by the time my wrist gave up.

Here it is in place, thankfully no unsightly gaps showing.

The pipe protrudes right through the base and the two are riveted together. At present they are held in the correct position with soft solder whilst I wait for copper rivets. It makes a nice chimney.

Next I turned my attention to the hinges and locking mechanism of the smokebox door. On the drawing supplied the hinges look simple and straightforward, just straight bars across the domed door, with two lugs on the smokebox face and a hinge pin through the lot. Not so ! For a start, the bars intersect with a compound curve, so not straight after all. Additionally, as drawn, the door perimeter extends beyond the hinge line, meaning the door closing face would have to be relieved for swing clearance, giving an unsightly gap (U.G.) You may have gathered by now that I can't stand U.G.'s The actual door was a little oversize which made things worse, and I decided to move the hinge line outward with revised offset lugs. The hinge bars had first to be milled to an approximate fit on the curves …..

… then filed and chamfered until a reasonable mating occurred ….

, after which the front faces, comprising two facets, were milled

Bars are currently screwed to the door but will soon be riveted. The latching and locking components, as supplied, needed some modification. With no drawing of this part I made it up as I went along. The hand wheel boss is much smaller than the boss on the door and didn't look right at all, so I turned a brass washer to transition from one diameter to the other, and it looks a lot better.

The door now swings freely and sits and locks nicely flush, the latch engaging in a removable slotted crossbar.

With a little riveting still to do the smokebox assembly nevertheless is an attractive addition to the front of the locomotive. I'm sorry this shot is sideways.

Thanks for viewing,

Ken.

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