Guys, thanks for all your help. Remember though some of us are not machinists by trade and are figuring stuff out themselves so we don't really know what the basics are to go back to. I started making this part back in 2009 so I thought it was a pretty trivial thing to make but on this (big) batch, things went haywire. I suspect a lot of the problem was not being able to accurately centre the hole under the countersink on my entry level drill press and compound vice. Once I squared up the jig in my little mill and indicated it in with an edge finder (another first for me), most of the problems went away. Having a machine which needs belt changes for every speed change is not a good thing but I am working on a remedy for that! Hopefully, I will have my new lathe by the weekend and my existing machine is on eBay as we speak.
Jack, thanks for the link I'll save that one for reference.
Gus I look forward to the beer! When you describe it that way, I can understand why you spend so much tie in your shop! I am sure now that you have isolated the cause of your wheezing, and applied the Makita remedy, you will outlive them all AND keep all your fingers!
