Drill Bit Advice

[Mikegtr]

I want to drill a few small holes in a steel hand saw using an electric hand drill. I have done some research and the drill bit to get for steel would be a carbide bit. From what I have read carbide drill bits should not be used in a hand drill. Is that so? What drill bit would you recommend and preferred make?

 

[Deadeye]

I want to drill a few small holes in a steel hand saw using an electric hand drill. I have done some research and the drill bit to get for steel would be a carbide bit. From what I have read carbide drill bits should not be used in a hand drill. Is that so? What drill bit would you recommend and preferred make?

Cobalt. The reason you get advised against carbide is that it's brittle and can break if your hand wanders during drilling. https://fmcarbide.com/blogs/techtalks/cobalt-vs-carbide-drill-bit

 

[Sideways]

Local toolstation or screwfix and get a "cobalt" jobber drill bit.
These are made of a high speed steel alloy with 5 or 8% cobalt that greatly improves their ability to survive and cut through harder steels.
To be honest an ordinary HSS bit will probably do the job but "HSS-E" cobalt bits will do better and it's handy to have a couple in the toolbox for stubborn steels.
You pay a little more but they are not silly expensive.
Cobalt bits are IMO a must have for drilling stainless which can quickly blunt ordinary HSS.

I have no idea why you are seeing stuff about not using tungsten carbide tipped cutters in a hand drill. We use TCT tipped masonry bits in handheld power drills all the time, I wouldn't think twice about using a TCT tipped holesaw in a cordless drill or a TCT spearpoint glass/tile drill likewise.

 

[ChaiLatte]

I have no idea why you are seeing stuff about not using tungsten carbide tipped cutters in a hand drill.

He did not say that. He said 'carbide', no more, no less. Nothing about tips, whether for saws, sores, pumps or billhooks.

He is more likely referring to a _solid_ carbide drill, which as the reply above your own points out, is brittle and needs a rigid machine to drive it lest it break.

 

[Spectric]

I think that the cost of a Carbide drill bit would put most people off using one in anything other than a drill press or a mill and in a production enviroment.

https://www.cromwell.co.uk/shop/cut...ls/carbide-drill-4mm-q-coat-3xd/p/SWT1583540S

 

[pgrbff]

I believe this type of drill bit is recomended to cut through hardened saw plates, at least they are the type suggested and sold by a handsaw maker in the US.

 

[Cobbs]

I've made a few bladed items from old saw blades, but not wanted to go down the road of annealing, hardening and retempering, so have just used a very fine (tiny but hot) blow torch to locally heat where I wanted to drill. The HSS bits went through no bother after that and the locally soft bits seemed to have no impact on the temper of the rest of the metal.

 

[cmoops2]

He did not say that. He said 'carbide', no more, no less. Nothing about tips, whether for saws, sores, pumps or billhooks.

He is more likely referring to a _solid_ carbide drill, which as the reply above your own points out, is brittle and needs a rigid machine to drive it lest it break.

Cracking application of a liitle-used word (lest) ...

 

[Wood4me]

Cheap tungsten tipped masonry drills are easily reground to give a sharp cutting edge at similar angles to normal HSS drill using a diamond disc in a dremel.

 

[AndyP]

These Erbaurer bits from Screwfix are good. I used them for drilling out stainless screws recently.

 

[Sideways]

He did not say that. He said 'carbide', no more, no less. Nothing about tips, whether for saws, sores, pumps or billhooks.

He is more likely referring to a _solid_ carbide drill, which as the reply above your own points out, is brittle and needs a rigid machine to drive it lest it break.

Fair point. If my solid carbide end mills are anything to go by, they are also ground to a near mirror finish along the shank and I imagine a 3 jaw drill chuck wouldn't get a good grip on them.

 

[Mikegtr]

Many thanks for all your replies--much appreciated.

 

[Ollie78]

I like the Heller ones from machine mart, good and cheap.

 

[Spectric]

If looking for high quality drill bits for metal then look for Swiss Tech / Dormer but for wood I find the spur bits from

https://www.alpen-drills.com/en/product-range/drills-for-wood-32/

good allround value.

they are also ground to a near mirror finish along the shank and I imagine a 3 jaw drill chuck wouldn't get a good grip on them.

Maybe not good for the threads either clamping them in a collet chuck.

 

[Fergie 307]

I like the Heller ones from machine mart, good and cheap.

I use their very small fraction of a mm drills for watchmaking. They always cut well but seem to have a bit more give in them than others, so don't break as readily.