Drilling metal

[David bonner]

Abolt what type of bolt a screw head bolt or a nut head or a Phillips head bolt and or a pointed end bolt?.

 

[eribaMotters]

Really? just use a smaller screw! .. cheers buddy! hadn't occured to me.

....

But no, thank you for pointing out the obvious, but I wasn't using a screw. I needed to enlargen the hole slightly (by about 1mm) to get a bolt through. And no, I couldn't use a smaller diameter bolt as it needed to fit the threaded hole that is already in place.

Get a strip of timber 70 x 25 mm, drill and countersink or counterbore two holes in it and bolt to the metalwork that is already tapped. You can then easily fix the clips wherever you need them with ease.

Colin

 

[transatlantic]

I appreciate you're trying to help, but for what I am using this with, I really did just want to enlarge the hole.

As suggested, I tried with a grinder and it did the job (I used a dremel with a cone shaped bit)

 

[TheTiddles]

So is sprung steel harder than stainless steel then? as the description in the link I posted for the drill bits says they're suitable for stainless steel.

In general yes for the types you will mostly come across, but there are hundreds of types of spring steel and thousands of types of stainless, then you can treat them all differently to adjust their properties, so asking for general properties of either is like saying “what’s the best food?”

Aidan

 

[Stevekane]

Its funny but somtimes you find that opening out a hole in metal can actually more dificult than just drilling a hole, its to do with the pointy bit of the drill not having anything to do, your just relying on the flutes being sharp and hard enough to cut through, well thats my experience anyway,,

 

[RobinBHM]

Stepped drills are great for thin metal...not sure they would like spring steel though.

Engineers use quality drill bits like dormer.

And using a drill press makes drilling easy

 

[Echo-Star]

Yeah but if the hole is too big and the screw is of to small then your buggered because the clip will fall out of the hole also there’s another way get the screw and place a washer over the hole.to hood it all.

Simple ideas are always the best

 

[KimG]

reply was redundant so I deleted it.

 

[woodfarmer]

I had some bosch drill bits from screwfix in my van to get me out of the poo if I forgot my good set. They were absolutely shocking, I don't know how bosch dare put their name to them! I tried to drill a piece of 3mm stainless (something I do a lot, so it's not like I don't know what I'm doing) and the bit just wouldn't touch it. Borrowed a dormer one from the on site engineers and it went straight through, so its not like the steel had work hardened. They went straight in the bin after that.

I also bought a set of botch drillbits, turned out made in China. first one bent drilling through corrugated roof sheet. The rest failed miserably so all I have left is two I wont use. 95% of Good bits that fail are due to too high a speed and consequently running it without cutting. You then have a basic fire making setup. DRills with 5-8% of cobalt work well. just make sure you keep them cutting and don't let them get hot so slowish speed. The speeds recommended are for production use where tool life is costed against time of running expensive machinery. I have one hss drill (1 3/16ths) which gets used fairly often which was last sharpened by an old guy in 1970. and it is only now begining to show signs of getting blunt. I have always run it dry but at a very slow speed.