Step drills

[Keithr0]

Any opinions out there? I always thought of them a butchers tools, but
I'm seeing them used a lot on the internet for sheet metal work. I
suppose that it saves using a separate pilot drill.

[Xeno]

Far better than using a hole say for, say, antenna mounting.

--
Xeno


Nothing astonishes Noddy so much as common sense and plain dealing.
(with apologies to Ralph Waldo Emerson)

[Daryl]

On 17/1/2024 6:48 pm, Keithr0 wrote:

The sparkies I used to work with doing solar installs used them all the
time, much easier than have a box of hole saws and charging arbors all
the time, also a lot cheaper.
Not good if you need a hole with a precise dimension but very good for
making a hole for a cable to pass through a metal roof or for holes in
plastic electrical boxes.


--
Daryl

[Noddy]

They're great.

The problem with sheet metal, and especially for larger holes, is that
the flutes on a conventional twist drill can grab very easily, and make
a mess of either the hole or the operator or sometimes both. Stepped
drills work well because each step acts as it's own support and keeps
the drill centred in the hole while making the cut.

They work best on sheet metal, but they're not limited to that use. I
used them on anything up to around 5mm if I just have to drill a single
hole, and was using one today as it happens to drill through a 3mm thick
diff housing to install a custom made drain plug bung.

On thicker materials spiral flutes leave a cleaner hole, whereas on
sheet metal spiral or straight flutes don't seem to make much difference.

--
--
--
Regards,
Noddy.

[Trevor Wilson]

On 17/01/2024 6:48 pm, Keithr0 wrote:

**I bought my first step drill about 20 years ago. American made. Cost
me a fair chunk of cash. Worth every cent. One nice thing about (my)
step drill, is that it de-burrs the hole, as it drills. I have a couple
of cheap, Chinese ones. They work fine, but my American made one is
better and doesn't seem to lose it's edge.

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[Noddy]

On 18/01/2024 8:21 am, Trevor Wilson wrote:
> On 17/01/2024 6:48 pm, Keithr0 wrote:
>> Any opinions out there? I always thought of them a butchers tools, but
>> I'm seeing them used a lot on the internet for sheet metal work. I
>> suppose that it saves using a separate pilot drill.
>
> **I bought my first step drill about 20 years ago. American made. Cost
> me a fair chunk of cash. Worth every cent. One nice thing about (my)
> step drill, is that it de-burrs the hole, as it drills.

Most of them do. In fact I can't recall seeing one that doesn't. The
leading edge of the next step acts as a countersink to help get the next
size bigger hole started.

> I have a couple of cheap, Chinese ones. They work fine, but my American made one is
> better and doesn't seem to lose it's edge.

Depends what you're doing with them. For basic sheet metal work the
brand or type doesn't seem to make much difference. For thicker stuff a
quality spiral flute drill makes all the difference in the world.

[Clocky]

They're brilliant, I use them all the time. The benefit of using a step
drill on sheet metal (or plastic when fitting 12V sockets and what have
you) is that they don't grab and twist which not only fucks the hole but
in the case of metal can potentially cause injury.

I even use mine on 3mm-4mm steel plate without any problems so far from
being a 'butchers tool' they are the opposite of that. I do drill a 1/8
pilot hole first though.

--
In thread "May need to buy petrol soon" Sept 23 2021 11:15:59am
Keithr0 wrote: "He made the assertion either he proves it or he is a
proven liar."

On Sept 23 2021 3:16:29pm Keithr0 wrote:
"He asserts that the claim is true, so, if it is unproven, he is lying."

[Keithr0]

Thanks to every-one who responded, I stopped by Total Tools and bought
one. I was attracted to a Milwaukee made from unobtainium, but settled
for a simple HSS item with a spiral flute, most of my work is in
aluminium so it should suffice.

[Trevor Wilson]

**Nice. You avoided the Milwaukee tax.

[Noddy]

On 23/01/2024 5:41 pm, Keithr0 wrote:

It'll do fine.

> https://ibb.co/whfkzNk

That's a no name brand "wrong-Fu" HHS sprial flute step drill cutting a
30mm hole in an 8mm thick steel diff housing, and it does it pretty
easily. Keep the RPM at a respectable level, use a lubricant and it will
last for some time. So much so that you'll wonder why anyone bothers
buying the expensive ones :)

If you're wondering what lube to use on Ally then Kero works. CRC556 is
very good. This stuff works on anything and is a great all rounder.

> https://crcindustries.com.au/crc-trefolex-cdt-cutting-oil-300g-3063/

[Clocky]

Use lubricant when drilling.