As is the custom in these parts, especially when the sun shines, it is now beer o'clock. The w/shop has been abandoned for the day, and photos taken have been up loaded to the P.C. Beer pot to hand.
On looking back at this thread I seem to have neglected it a tad, so I will attempt to catch up.
The big ends housings were tidied up a bit (I think there's a bit to go yet, perhaps a few corners to go) and the rods taper turned, threaded and attached. Threading was done in the lathe and chased with a die I find that the quickest simple way to get a true thread, the die always seems to leave a better finish than the tool.
- Con-rods (2) (600 x 450).jpg (69.25 KiB) Viewed 13232 times
Whilst not a lot physical was going on I was allowing my two brain cells to rub together and eventually I've come up with my solution for the cross-head guides and mountings. Material choice is silver steel, however, whilst round would maybe do, I preferred square. A slot would be provided in the boss of the bottom cyl cover and a cross-bar fitted on the pillars to attach the bottom end. The cross-heads would be brass/bronze with a yolk small end on the con-rod with the gudgeon (wrist) pin fixed in the cross-head. (I hope that's all clear). Problem one. No square silver steel available in the required size (1/2"). I don't know about on the lee side of the pond but over here things like this are a problem generally, some materials are just not there! The only option was to make some round square!
Across corners of 1/2"square is a touch under 18mm which just happens to nicely sit in one of the 'T' slots on my mill. Clamped at both ends and a floating clamp in the middle 0.100" was removed. 0.100" is not quite enough, but there is a method in the madness (0.104+" would be more correct).
- Crosshead Guides (3) (600 x 450).jpg (71.87 KiB) Viewed 13232 times
Bar turned over and repeat on the other side.
- Crosshead Guides (6) (600 x 450).jpg (67.85 KiB) Viewed 13232 times