Starting the yoke

Time to make the yoke. A bit different to others I've seen in that the block will be a little cylinder travelling up and down inside another - seems like a sensible design as it'll help to keep everything square (while being round :D ).

So, phase 1, make the upright and cross drill for the horizontal piece. Took longer than anticipated as I couldn't find any 1/2" or near brass stock so had to turn down a length of 1"! No matter. That done, it could be cross-drilled to accept a piece of 1/4" brass rod (threaded through to accept the piston rod and ram connections). Here are those bits assembled (with some screws inserted to check alignment) ready for the next step - more soldering.