I use two halves of a nut to install or remove studs. I saw the nut with threads that match those of the stud’s in half from point-to-point. Then I place the halves around the stud and grip them with vise grips to get a good hold on the stud.
Typically I use “easyout” extractors to remove broken studs, but if I don’t have the appropriate set readily available, the tang of a file often does the trick.
Start by drilling a hole through the center of the stud, making sure the drill diameter is no larger than half the stud diameter to avoid expanding it in the hole. Drive the tang of the file into the hole and turn the part of the tang above the stud using an adjustable wrench. If the stud does not move, try first screwing inwards, as this can break the seal. You may also need to tap the file tang in a few times more during the process.
Often, I use a small variable-speed electric engraver to remove a broken bolt or stud threads. This works especially well on small fine threads. Sometimes the rapid “hammer” action of the tilted hardened pin is all it takes, whereas using a punch and hammer makes the task more difficult.
Fixturing for cutter recycling
We mill parts using a lot of tangentially mounted inserts. On the one hand, they handle highfeedrate cuts, but on the other hand, they are simple in design, which makes them perfect candidates for recycling.
To recycle the inserts, I developed a fixture for removing 0.25 mm to make the inserts as good as new. We are then able to use the inserts for two or more applications, first for finish milling, then for machining chamfers, for example.
Tata Motors Ltd.
Need to tap a hole a bit oversize? Put some masking tape on the tap and run it through the hole a second time. Don’t know why it works, but the chips will be there to prove it.
I use a small matchstick or piece of wood the size of a matchstick carved off a bigger piece of wood to get a tap or reamer to cut a little oversize. Place the matchstick in one of the tap’s or reamer’s flutes and run it through the hole.
Another way to resize a reamer so that it cuts oversize is to run a carbide insert up and down the inside of the cutting flute. This raises a slight burr on one or two flutes and causes the reamer to cut oversize. The method works for one or two holes.