i’m pretty sure the hair dryer warmed up everything, and wasn’t
successful b/c of that. it might not be the best solution for a
small situation. unless you can keep the screw cold while heating
the surrounding area.
[you want the heat to expand some of the metal and at the same time
keep the screw from not expanding so it will turn out.]. vibration
is another way that might help. depending on how damaged the
screwhead is will play into this as well. slot or phillips head?
is the screw recessed into the plate or proud? is the head large
enough to get something like a locking brand of pliers on it?
make sure you’re using the right size screw driver.
can you lay the mill down so you can get a little more oily stuff to
flow down where the screw is, and apply more direct force? apply some
additional spray oil stuff try to make sure it is being forced into
the hole where the threads are:
=> you might use an old hammer to gently tap the head of the
screw[if you can without hitting anything else].
=> you could also tap on the screw driver while turning it. heating
and tapping might release it too…keep at it.
=> if that doesn’t work after multiple attempts/the head is beyond
repair, get to a hardware store and find a screw extractor. it is
sharp and digs in and bites into a hard to remove to help remove it.
i got a set from kmart recently, in the sears area of their hardware
dept. if that doesn’t work then you’ll probably need it drilled out
and possibly re-tapped.
i have a similar situation with a steel bolt broke off and stuck
inside the cast aluminium housing on my clay extruding pugmill. it
can wait till i can put it under the drill press and drill that
sucker out. maybe the maker should have furnished some plastic
threaded plugs to keep clay out of this area…
hope this helps!