From: Barry (btuttleman@worldnet.att.net)
Date: Sat Sep 21 2002 - 12:40:34 PDT
this is one of the reasons to NEVER use tap extractors; they will only
work if the broken stud/bolt is not stuck very hard anyway; but when u
break the extractor off (and it happens ALL the time), you know have an
extremely hard piece of metal that is impossible to drill - EDM or one
of the older tap "blasters" will be necessary, unless the extractor ex-
tends out of the block, at which point a nut is tack welded to the ex-
tractor and manually turned out. if the extractor had never been used
in the first place, the broken stud could have been removed fairly
easily (for someone who does this all the time) by carefully center-
punching and drilling out from small drills up to the tap drill size.
application of heat (torches) before attempting to remove specialty
area hardware (such as exhaust hardware that has been continuously
heated and cooled, forming heat rust which locks everything down) is
a common practice, but it still takes a good "feel" to read the broken
part - you CAN tell when it is going to break once you've done this
enuff. applications of heat and some penetrating oils can well assist
the mechanic; to PREVENT this next time, LIBERALLY apply ANTI-SEIZE
compounds (hi-temp in exhaust areas, other high temp engine areas) to
ALL HARDWARE; this will assist in easy removal when necessary. here's
the rule: if the hardware does not require Loctite compounds, then it
should ALWAYS be coated w/ anti-sieze lubricants. this comes from years
of fabrication/assembly/disassembly in the hi-tech world.
my friends machine shop sometimes makes a living just removing broken
hardware out of various parts - anything w/ a broken (left hand) tap
extractor proved always the most difficult to repair, and eventually
many had to go to the EDM'er to remove.
MAKE ANTI-SEIZE COMPOUNDS A NECESSARY ITEM ON YOUR BENCH; get used to
using it everywhere, and you will avoid this problem.
tnx,
barry
carson city, nv
This archive was generated by hypermail 2.1.4 : Wed Apr 23 2003 - 13:21:22 PDT