Okay, so, I just landed a new job at a small machine shop where I am Blissfully overqualified. I'm going to have free time on my hands filling out my 40 hours, and I plan on staying Late.
So, I need to drill some holes in a personal project sooner or later and I need some guidance.
I've got a whiz bang brand new CNC knee mill at my disposal, I can buy in tooling, and I'm going to be making fixturing for this, but it's tricky for a number of reasons. first of all, the Subject:
http://mjmotors.tumblr.com/post/1582917 ... rakit-from full writeup.
Those stud holes are in the wrong place for my application and there's Cast Iron about halfway down. I've gotta bring them In towards the bore a couple mm, I forget how many. Studs are 6MM diameter.
Whole thing is around 50mm deep. But modding this and making an adapter plate for the intake is all I need to finally have a 'correct' cylinder for This engine:
I was thinking of using a straight shank 7MM drill bit, slow, with a steel jig plate half an inch thick guiding the bit and lots of cutting fluid.
Oh, and a BIG shout out to Doc, and everyone here. I got this job because I've sat here and read the ancient scrolls penned by cranky elders for sixteen years.
I'd drill those holes and tap them to fill them, then drill new clearance holes using an drill if there's mostly old material, an endmill if you're starting in the fill. If you use permanent Loctite to glue the screws you fill with they'll stay for the machining, without you'll just break an endmill or drill. The reason for filling the old hole is to make sure that you have enough area for the gasket to seal.
If you really want to risk it w/o filling you have to use an endmill to take the material out, a drill will really want to wander off and break.