Stop drilling a crack stops what we call a stress riser..the end of a crack will concentrate the stress at that point..
Stop drilling is one of those go the extra mile deals on a car..Aircraft metal we always stop drill when doing a sheet metal repair..then we rivet a patch on the affected area..a bit different deal than cars as we are more concerned with the structural integrity of the part..for car guys the over ride is how it looks when done..gotta be smooth and not show any or very little evidence of repair when done. actually if all one is concerned about is the structural integrity one could use one of the modern panel bonding adhesives to "stick a patch" one the affected area..that is after one has stop drilled the ends of the crack..Might even work in some situations..!!!
The reaon we stop drill is the same reason one finds a small fillet on a crank at the intersection of the crank throw and the crank arms..gets rid of a potential stress riser..we also fillet weld chassis for the same reason..
Willys (Jeff) put up a post on stress risers some time ago but darned if I can find it today..
I have tried most all of it and now do what is known to work..
Last edited by OneMoreTime; 01-02-2006 at 12:05 PM.
Reason: Fixing spelling