On Feb 19, 6:29*pm, "Ralph Mowery" wrote:
I needed to replace some screws in a metal door hinge where I work *They
must have used some odd ball size. *I tried a #6 metric and it almost fit
but didn't. *Went to a 1/4 inch in the two number of threads and it was too
big. *The next size I could find was a # 12 and it did not fit. *The #5
metric was too small. *I found a new package of hinges with the screws and
they fit fine.

What are they using for the screw size in a metal door ?


Which sizes of machine screw did you try ?

1/4-20 is the most common, but there is also:
1/4-28 and 1/4-32

assuming steel door frame, you would drill
two different sized holes depending on the
thread pitch for a 1/4" machine screw:

for 1/4-20 you would use a 7/32" drill bit,
for 1/4-28 or 1/4-32 you would use a #1 bit...

The same logic applies to a #12 size
machine screw...

12-24, #12 drill bit, 12-28, #10 drill bit,
12-32, #9 drill bit...

So the "size" of the fastener makes a
difference as well as the thread pitch...

~~ Evan