Hi, I'm building a model beam engine (Stuart Major) and am starting on the connecting rod. This is a fairly faithful copy of full sized practice with bearing shells that are held by straps onto the end of the rod. The straps are held in place by cotters that have to pass through a rectangular hole 3/32 x 11/32 (about 2.5 x 9mm) which passes right through the end of the rod which is 5/8 thick. (tried to attach picture of drawing) The question is how do I accurately cut these holes ? It as to be fairly square with parallel sides. Milling with a slot drill would be tricky as even long series slot drills in this size are not long enough. I could drill a series of holes and then try to open this out with needle files but it would be really difficult to do this neatly. Has anyone got any ideas ?
+-------------------------------------------------------------------+ |Filename: Connecting rod.gif | |Download:- posted
15 years ago