What is this self tapping screw?

[nickz]

I have come across a few of these in my bolt bin, I have no idea what they are used for.,but I do know someone will here. Curious.

 

[alex71]

That's a wood to metal self driller. Looks like a 4 or 5 point. The reamer clears out the wood, then breaks off when it hits metal.

 

[nickz]

Thanks Alex71, I am sorry I still don't completely get it, can you give me a example of what it could be used for?

 

[nickz]

I'm guessing the metal would already be drilled to appropriate size?

 

[nickz]

Googled it , thanks! Had no idea.

 

[signcrafter]

Thanks Alex71, I am sorry I still don't completely get it, can you give me a example of what it could be used for?

I've used them for attaching 2x4 or 2x6s to steel I beams when framing walls. Sometimes called Tek screws but I think that's a brand.

I'm guessing the metal would already be drilled to appropriate size?

They are self drilling and tapping. And the ones I've used go threw Thick metal beams with no problems.

 

[dutchgray]

Good ones will self drill in heavy drill, cheap ones may not, then you either bin it and use another or pre drill slightly smaller.

 

[Thumper68]

When I am building boat docks I use a ton of these to hold the deck boards on, I like to predrill since the hot rolled angle has lots of hard spots in it.

The trick I found is to use a slower speed drill like the Milwaukee magnum 1/2.

 

[Tucko]

Yep. It's commonly called a Super Tek and the quality ones will go through steel like butter. However, the ****** ones need to be pre-drilled..