self tappers

[chunkolini]

I am making a structure for a customer and they are fixing wiring to it for lighting.
I am happy to drill umpteen holes for them to use standard self tappers or pop rivets but we have no idea where the holes will be needed.
The framework is being made of 30x2.5mm mild steel box section.
Would these 'self drilling' screws work?
https://www.screwfix.com/p/easydriv...pancake-head-screws-5-5-x-19-x-200-pack/1376h
Saves lots of spare holes and allows the installer to fit them where he likes.
Or these?
https://www.screwfix.com/p/carbon-steel-self-drilling-screws-5-5-x-25mm-100-pack/54743

 

[500e]

Yes
Would suggest the. Hex head on 2.5mm fine thread & either battery drill or tech gun
You will have a a small percentage that are blunt

 

[8ob]

Depends how thick the "structure" is, these things are not so clever on thick steel especially if working off a ladder where you can push that hard, the drill bit end of the screw just burns out.

Bob

Just noticed its 2.5mm, should be ok on that if you can get a decent push on the drill.

 

[The_Yellow_Ardvark]

Both are good, But can be a bit difficult in thicker metal.
I favour the hex head ones, the other can suffer from the head being mullered if you sue the wrong bit.

 

[tom2207]

Id be looking at fine pitch tek screws and the proper gun , then its a breeze

 

[Munkul]

+1 for fine pitch metal tek screws.

 

[chunkolini]

I was thinking the hex head version; Oh the joys of knackered pozi heads!
It will be being done by somebody else so I'd prefer something that can use a standard cordless drill.
Planning stage at the moment

 

[Munkul]

8mm heads with a magnetic driver in the drill - makes everything easy, in fact makes it quite a nice job, as opposed to fighting on with pozis or even torx.

 

[tom2207]

I was thinking the hex head version; Oh the joys of knackered pozi heads!
It will be being done by somebody else so I'd prefer something that can use a standard cordless drill.
Planning stage at the moment

they can be used with the screw driver type gun , But a real tek gun just seems to hit harder and they can be had for 100 quid ish , there really is no going back once you have one , its like hot glue for grown ups.

 

[chunkolini]

Sorted, decent cordless drill and hex head, tip about some being blunt was useful.

 

[Shedendman]

I use those hex heads on 3mm thick no probs as mentioned some do come up blunt,another tip is once your trough switch drill speed to slowest because they do go in rather quick

 

[500e]

We run them into RSJ with tech gun a tip if the are to long & protrude on other side a swift blow with a hammer nocks the excess off flush that works on Purlins & RSJ never done it on thinner\softer material
The types & style will leave you bewildered

 

[mike os]

if they have a drill they can drill a pilot.... then self tap, easier and a safer bet for numpties

 

[jsf55]

Get the magnetic bit holder, there so much quicker and easier and a few quid at most