Many thanks for the comments Stephen, Torbiorn, Richie, and Rick - much appreciated!
Having 2 days off this weekend enabled me to get some more bench (actually computer desk) time in yesterday. I had been putting off doing the induction piping because I'd not worked with the pipe function before, and honestly, I'm not convinced that I chose the best method. I'll explain in a minute!
After first watching the required youtube video I sat down and started on the design. I'm ok with adding planes to use as a base reference so that was the first job. To ensure that the pipe work was at the required distance from the cylinders I added a plane, then drew my spline on it. The outer pipes were built starting with a straight centre piece, then one of the cylinder manifolds was added. The ends were moved to the required positions to add the bends and that was about it! Simples!
Only it wasn't, because I had to tweak the spline quite a bit to adjust the curvature, ensure it was straight where it needed to be straight, and that the general look of it all was right. Once I had one done it was simply mirrored - another plane added for that excercise. The longer pipe was done as a copy of one of the shorter ones, lengthened, and moved to the correct position. Re orienting it took a while because I couldn't figure out how to add an axis to rotate it around, but I finally figured it out and it was simple from then on. Again, once complete it was mirrored to the other side. The final centre piece was a very simple spline with a bend either end and a cylinder added for the upright.
So what did I get for my entire afternoon's graft?
Here's one of the larger pieces
and all 3 together
I printed 4 of each so I had plenty of spares and used 2 different print orientations to see if that made any difference. I'm pretty pleased with how they've come out!
As for my comment above on pipe not being the best method to use, I say that because the ends of the pipe are not at the correct angles. It won't notice in this scale but in future I think I'll add a cylinder first to get the square ends to the cylinder head end, then add a pipe to that, or maybe even two cylinders with a radius added at the joint.
They are just resting in place in those pics and will need a little tweaking but nothing major. Or I may not bother as they are so small anyway!
On a final note, when I printed the cylinders previously I again used 2 different orientations. I hadn't noticed before and thought the vertical ones ere good, but when I looked closer at the slanted ones I realised that the valve rocker assemblies had not printed fully on the vertical ones, but with the extra supports I had added to the slanted ones, they printed fine. I had forgotten that I had eve designed those in!
I'm starting to lean towards using a resin crankcase from an Argus engine instead of designing one. It's close enough, won't be seen, and I really want to get on with actually building this!
Thanks for looking in!
Ian