OS SF you say, interesting. I wonder if original parts will fit this Royal then. I see that Tower hobbies still has some replacement parts. My engine is in the mail and uncertain of it's condition. Not an eBay purchase but rather a handful of engines from a friend.

As to finding some low cost engines suitable for conversion, that is just what I have doing to - digging around to find some suitable candidates. I am even planning on making a sparky conversion too. The Royal is the most likely candidate for the diesel and I have a plane for it go into. A McCoy .29 redhead as the possible candidate for the sparky.

Making parts isn't that hard, just takes a bit of planning and trial and error. It sounds like you have everything you need to have a go. I have only a small Taig lathe with milling attachments and it is getting easier with each project as I work my way from simple to the more complex. I hope to one day make my own little diesel from scratch.

cheers, Graham in Embrun near Ottawa Canada.