What are these self tapping screws called that form "real" threads?

I'm looking for some screws for use in production work.
*Sick of tapping lots of M4 and M4 holes.
*
Used for attaching small brackets and DIN rail etc.
*Fixing to to mild steel 3mm thick or to 1.6mm thick Zinc Anneal sheet.
I've seen screws like in the links below but am having trouble finding
them. When I look for self tapping screws I find the coarse thread type
rather than the defined M4x0.7 or M5x0.8 threads.
Is there a proper name for these screws:


Thanks.
Reply to
Techman
Loading thread data ...
I'm getting closer.
Some seem to be called Taptite,

And others "Type 23"

Reply to
Techman
This Fastnal document may help:
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Go to page 59 and look over the "Types of Screw Points". The "Tri-lobular" point may work for your needs too...
Reply to
Leon Fisk
Google on "thread cutting screws". Even Amazon sells them :-)
Reply to
John B.
Yep - thats them. Thanks.
Reply to
Techman
Thanks John
Reply to
Techman
They are called thread forming screws.
Reply to
clare
On jobsites, I've just heard them called tappets.
Reply to
mogulah
More likely Tappits. - but PK Tappits are used in sheet metal 0 they are NOT thread forming screws.
Reply to
clare
Must be regional, in Oz, Tappits are plastic plugs with a nail in them that are used for hanging pictures or affixing to brick or concrete walls.
Reply to
Techman
Yeah, I've seen those and wondered what they were called.
Yup, that sure looks like the type you wanted. I've been using Type 17 self-tapping deck screws in the recent past.
Reply to
Larry Jaques
Note - I qualified my statement with the brand - PK Tappits is a registered trademark.
Reply to
clare
Those taptites are thread forming scres.
Those type23 scres are thread cutting screws.
Reply to
clare
Recently, I've had a rash of blast media (small clear crystals) in the philips head slots of micronized galv deck screws. They're also too hard, breaking where the thread and shank meet or up next to the bugle head. A few out of a 25# box isn't much to consider, but sometimes it was a few out a single handful of screws.
Yesterday's client wanted me to use an EasyGate kit. One of the included screw's head was missing the philips depression altogether. I guess you're supposed to drive those in like nails, eh?
Reply to
Larry Jaques
So that's why they call a hammer an Amercan Screwdriver.
Reply to
fred
Of course you put screws in with a hammer. The slots in the head are only there to take them out :-)
Reply to
John B.
Yep, I did. ;)
Reply to
Techman

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