crank shaft thread damage
Glad that worked. I took notes, in case I need this info later. 
Don't waste money on various dies just to repair external threads, like a bolt. Although that works, you need to buy one for every different bolt you might screw up, and that gets expensive. Get one of these instead.
http://www.grainger.com/product/NICH...set&s_pp=false

Don't waste money on various dies just to repair external threads, like a bolt. Although that works, you need to buy one for every different bolt you might screw up, and that gets expensive. Get one of these instead.
http://www.grainger.com/product/NICH...set&s_pp=false
Once the metal of the threads, internal or external, are damaged, you cannot "repair" them. Damaging threads means shearing off the thread at it's root or crushing it flat. Running a tap into say a damaged crank will clear out the damaged threads allowing the bolt to turn in and reach good threads. The trick is getting the tap through the damaged section and still being inline with the good threaded section. If it's off, the tap will remove the good threads.
Hardened steel nuts and bolts are not made of soft stuff that can be put back in place. Once threads are compromised, they have no strength.
This is required reading (RIP Carroll Smith):
Hardened steel nuts and bolts are not made of soft stuff that can be put back in place. Once threads are compromised, they have no strength.
This is required reading (RIP Carroll Smith):











