During a lull between projects, we utilized our haas machine to perform partial machining on this large engine, as our other machines were too small for the job. Our goal was to smooth the surface of the engine and create space for a new custom cylinder piston. Unfortunately, many of the stud bolts were badly corroded, so we decided to grind them off to avoid potential damage, as they were likely to snap off and take a piece of the surface with them. To avoid damaging the original threads, I created a specialized program to bore the studs in a counterclockwise direction.
Facing the Mercedes Engine block.
The depth of the Cylinder is 200 millimeters
I have two methods for removing old, snapped-off stud bolts. Firstly, I locate the center of the stud bolt and then use a counterclockwise helix bore program with G43 to gradually widen the hole until I can see the old threads. Then, I use a small tool to push the old thread out and a pair of pliers to peel it away. Once this is done, I re-tap the hole and check to see if it is still tight enough to hold a new stud bolt. If it is too loose, I install new timeserts. The second method involves pre-boring the hole to a fixed size, inserting a tool with teeth into the hole, and using a ratchet to undo the old stud bolt. There are many ways to do this, but I prefer to work smarter rather than harder, and since it’s on the machine anyway, I want to be as efficient as possible.
