"Glenn Ashmore" wrote in
news:w6B0f.429$784.384@lakeread08:


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?


3 mm will be pushing it. Have you looked at LHSHCS? (Low-Head Socket-
Head Cap Screws).
Check:
http://www.mcmaster.com/itm/find.ASP?
tab=find&context=psrchDtlLink&fasttrack=False&sear chstring=93070A215

Head height is only 6 mm, leaving you 15.5 mm of material thickness
without a washer (0.5 cbore clearance), subtract another 1.25 mm if you
use a serrated cone (bellville style) lockwasher.

Anthony