pyotr filipivich wrote:

"Michael A. Terrell" on Wed, 07 Sep 2011
15:24:31 -0400 typed in rec.crafts.metalworking the following:

pyotr filipivich wrote:

"Michael A. Terrell" on Wed, 07 Sep 2011
00:23:18 -0400 typed in rec.crafts.metalworking the following:

Gerald Miller wrote:

OTOH, Robertson drive fasteners are automatically held in place by the
tapered mating surfaces of the driver.

Not the ones I've seen and had to remove. Every damn one of them was
sloppy, and I burnt up a bit about every six screws because they would
wear down the corners till they just spun in the screw heads..

Is that a problem of the bit design, or of the bit construction?


I have no clue. I used new, brand name bits on existing screws in my
garage. The former owner had built racks that hung from the roof out of
2x4s and plywood. they weighed several hundred pounds each, and hung so
low they were in my way. I never want to see another of those screws
again since I had to remove the damaged heads with a surface grinder,
then use a crowbar to pull the wood off the threads. Then I had the fun
of removing the damaged screws with vise grips. At one time there were
a half dozen mobile factories around here, and the place was crawling
with surplus hardware. The used barrels of those damn things, and a lot
of it ended up at the local building surplus dealers. they may have all
been rejects, or salvaged by the original owner. He was the local 'Mr.
Fixit' for the subdivision and I don't think that he ever did anything
right.

Hmmm, sounds to me like a "special case" where the screws had "set
up" in whatever they were sunk into, and were not going to come out
easily, regardless of the drive type. I've had a few of those myself.
Such an experience can color one's opinion of the product. OTOH,
Robinson heads do work well for installs.

Does anyone still use slotted head screw?


Yes, for electrical work.


--
You can't have a sense of humor, if you have no sense.