30 degree C in the workshop, but with the door and all of the windows wide open I spent some time turning the crosshead guide and then slot drilled the open sides.
At first I was worried about the size of this crosshead, but I offered the unit up to the traction engine and it looks ok. This traction engine is going to be stand-off scale as I have used quite some licence to achieve 1/20th scale.
Looking very nice, well proportioned and still shiny. Many years ago I turned my hand to a 2" Burrell compound showman's engine. Had me in tears at times but in the end I managed to finish it. It sat in my living room gathering dust and cobwebs until in the end I sold it and bought a new Triumph 900ST. The local gun shop, who was a client of mine, got me into long rand pistol shooting so I ended up making my own long rang pistol. More toys. Shooting pistols at up to 1000 yards on Stickeldown Range at Bisley. Not bad for a pistol. Sat on a sand bag, bolt action, 12" barrel from Doug Shillen, 2oz trigger, Burris 10x scope and wildcat 460 Wetherby necked down to 30 cal. 0.1" group at 200 mtrs. Great fun until our bloody government banned the hand guns. Enough of this twaddle, I am now building a Stuart Turner Major beam engine and having great fun doing it. Will attach a few photo's as it comes along. Anyway, I am now going to go out for a ride on the current motorbike, A Yamaha Niken. Funny looking thing with 2 front wheels, goes well though.
In the mean time everyone enjoy our hobby and stay safe.
Graham T. South coast of the UK.
Now onto the crankshaft. If you remember my earlier design discussions I was struggling to see a way to getting a 6mm throw and hence 12mm stroke. Well, there are a few things that help this: 1. offset of the cylinder and curvature of the firebox 2. ability to lift the bearing blocks slightly 3. two-piece crankshaft and hence single piece conrod big-end.
So here is a sketch of the crankshaft:
I assembled and silver soldered this with a single piece main shaft. That made it easy to align everything and machine surfaces. One of the last actions was to then split this main shaft and machine back to the internal web faces.
Just to prove it still splits into two and that I didn't make a mess of the silver soldering:
A little bit of cleaning and then a polish and this will be ready. And change the bolt to something more subtle!