I have been going through a lot of old e-mails and things trying to get back into regular updates.
As I have been going through the mail I see a lot of requests for metric versions of plans. It would seem simple to just multiply the inch dimensions by 25.4 to convert to mm . But we all know engines can be scaled up or down some so I always recommends just multiplying the inch dimensions by 24 for a model about the same size and by 32 for a slightly larger version. The advantage of 24 or 32 is it gets rid of lot of the fractions that appear in inch designs.
The difficult problem is converting the screws and gears to the metric equivalents. Most of this information, on my drawings at least, is in comments and needs a lot of review.
I am about 2/3 through the drawings for my Horizontal Hit and Miss. I hope to have a set of prints on line in January 2014.
Since my shop is presently half here and half there I am focusing on drawings and future projects. I plan on building a back yard foundry and try casting aluminum engine parts. I am also thinking about a 3D printer to make the patterns for investment type casting of engine parts.
Take your inches to 4 decimal points and convert that to millimeters to 2 decimal points. Present your numbers in the drawings and all the original gears and bearings will still work. Let the builder decide weather to bore holes or buy imperial reamers.