In article w6B0f.429$784.384@lakeread08, says...
I need to make a couple of adapter plates for the new 56HP Yanmar to fit
the CV
joint to the prop shaft. The gear box flange has four M10x1.5 threaded
holes on a 78mm
pitch circle and the CV joint has six M10x1.5 holes on a 93mm pitch circle.

At anything other than a 15 degree offset between the two circles the holes
interfere. At 15 degrees I have 3mm between the holes. I am limited to
22mm in thickness so I can't drill blind holes on either side. Is 3mm
between holes sufficient or is there another way to lay out the bolt
circles?



I can't imagine why it would be a problem with a reasonably strong and
malleable material (e.g., mild steel or 300 series SS). Consider that
the wall between the holes at the thinnest point is only 0.5mm less than
the wall of a standard M10 nut.

Is there a specific failure mode you're concerned about?

Ned Simmons