Type of drill to get?

[rewireIT]

I know what you meant and suggested using smooth cutting hole saws in an impact driver.

These things.

But then when i want to start screwing stuff in i have to change bits. I find it more economical to have all my screwing done with the impact and all the other stuff done with the combi

 

[rewireIT]

I'd go with a combi first as it's quite versatile, then an impact for the "oomph" when you really need it, like setting muti-montis into concrete. Also, while I agree 2 decent sized batteries are ideal, I like a small 1.7Ah when drilling at height or above my head as it is much lighter.
As for hole saws, well I very rarely use them. If I need a hole in a metal box etc I use a hole-punch. There's no "chattering" on the enclosure which is nice, especially if it is populated, and you get a nice clean cut, albeit I run a Noga round the hole to deburr even though it's not usually necessary. If the box is installed close to a ceiling, for example, it's difficult to get a drill on top, so the punch wins by being so compact.
If the box is of thin metal then a pilot hole of 5mm followed up by a cone or step drill. Anything except attack it with jagged teeth whirly round thing!

nice.

how many cuts do you get out of each punch?

 

[nicebutdim]

But then when i want to start screwing stuff in i have to change bits. I find it more economical to have all my screwing done with the impact and all the other stuff done with the combi

I wouldn't have made the suggestion, had your earlier post (quoted below) not been at odds with the above.

I must admit for everything except drilling out for stuffers and drilling through joists i use the impact.

There are also very capable bits available for drilling through joists with an impact driver, providing exceptional speed and requiring minimal effort.

Assuming your latter statement is correct, I'd encourage you to try making more use of impact drivers. In my estimation, they're up there with the multi tool in terms of 'how did we manage before their invention?' and are very versatile tools which adapt to multiple tasks with ease (mashing the insides of dist boards excepted).

 

[nicebutdim]

As for hole saws, well I very rarely use them. If I need a hole in a metal box etc I use a hole-punch. There's no "chattering" on the enclosure which is nice, especially if it is populated, and you get a nice clean cut, albeit I run a Noga round the hole to deburr even though it's not usually necessary. If the box is installed close to a ceiling, for example, it's difficult to get a drill on top, so the punch wins by being so compact.
If the box is of thin metal then a pilot hole of 5mm followed up by a cone or step drill. Anything except attack it with jagged teeth whirly round thing!

I've looked at punches many times and really like the idea, but can't help feeling they'd end up as another unloved item in the bottom of a tool box, due to more efficient means of cutting holes.

What appeals most about punches is the idea of a clean cut, with no swarf. The smooth cutting holesaws I linked earlier do produce lots of tiny metal chips, but leave behind a very clean hole and cut smoothly, without any chattering. The also have a lip that prevents protrusion into enclosures.

The only issue I have is their price.

 

[pc1966]

how many cuts do you get out of each punch?

Hundreds if you look after it. Mostly making sure the bolt/nut is lightly greased and kept clean of swarf. You can usually replace the bolts part as well.

They make for a clean hole, slight burr on the pushed-into side, but quiet and free of swarf other than the pilot hole. If you need a medium size hole in sheet metal (say to 2mm steel) they are very attractive, though bigger ones need a ~20mm pilot so cone drill, hole saw, or two sizes punch operations needed.

Here are examples:

Q Max Sheet Metal Hole Punch Metric | Hole Punches

Buy Q Max Sheet Metal Hole Punch Metric and other Q Max Hole Punches at Tooled-Up.com. Fast Delivery.

www.tooled-up.com

For smaller sizes, say to 20mm or there about, a cone drill or Armeg hole saw work as well, if you don't mind swarf (i.e. cutting before installation, without electrics to get contaminated with it). While I have hole sawed to 110mm its not a great experience and rarely that accurate a hole at the end of the day, a hole punch is far more civilised.

You also get square punches for switches, and special shaped hole punches for the likes of coax connectors (single 'D' for BNC, double D for Type N, or etc) that are great if you need them, but price is surprisingly high, as in £100-200 or more.

 

[nicebutdim]

While I have hole sawed to 110mm its not a great experience and rarely that accurate a hole at the end of the day, a hole punch is far more civilised.

For you or the gears in your drill?

To be fair, few electricians will be using holesaws above 64mm in steel. Larger sizes tend to be used in more forgiving materials and, if cutting a number of large holes (160mm+), I'd switch out the SDS chuck and let a bigger drill handle the strain.

 

[pc1966]

Here is an example of a D style punch:

Single 'D' Punch Unit - The Cable Tooling Company

Get next day delivery when you buy the Single 'D' Punch Unit from The Cable Tooling Company.

www.cabletooling.co.uk

RS and Farnell list far more Greenlee special hole punches, but prices are around double of those folks. Having said that, RS is often ex-stock while they are on demand and can be many weeks. Here is one I got recently, but not at this price:

50124749 | Greenlee Punch and Die Tool, 43.4 x 12.9mm, 25 Way D F, Hydraulic Operation | RS

uk.rs-online.com

They say "hydraulic operation" and you can get, at great expense, a matching hydraulic actuator but by default it has a nut and bearing so can be done using a spanner or socket set.

 

[pc1966]

For you or the gears in your drill?

Both!

Was for some waste pipe as a cunning entry route for cables.

To be fair, few electricians will be using holesaws above 64mm in steel. Larger sizes tend to be used in more forgiving materials and, if cutting a number of large holes (160mm+), I'd switch out the SDS chuck and let a bigger drill handle the strain.

True, it was unusual and as you can see above, not amenable to a hole punch anyway for all sorts of reasons!

 

[MJPD29]

I would recommend Milwaukee. I’ve only had good experiences with their tools and tend not to vary because they are the batteries I have. M12 range and m18 range are both great, m18 being considerably more powerful but larger and heavier.

 

[pirate]

How many holes with a punch?
As @pc1966 said, hundreds if you treat them right!
Never at the bottom of my toolbox, I have them in a dedicated box, ready for use, and look forward to using them!
A very nice young spark came to fit a new DB at the charity place I do work for. I had run all the cables and installed the sockets and lighting etc and he came to put in a new, bigger DB. He couldn't get his drill and hole saw anywhere near so I lent him my 20mm punch and he had never seen one before. Punched 2 holes in DB and 2 more in trunking. He emailed me later that day to say he had ordered 4! I guess it's just horses for courses. We all have our favourites, and maybe it just takes a new approach to find something else?
I just like tools that do the job with less noise and disruption...but I'm old, so sometimes folk look at me and ask why I use such and such a tool. I reply it's because I research, research, research...I have the time, I am retired, I don't need to save 5 minutes per point...but I get the satisfaction of doing each point to the best of my ability. Be open to different ideas, that's all I do.
The satisfaction I got using my impact driver to drive 200mm coachbolts into timber decking posts was immense!

 

[pirate]

As an aside, check out the price for Milwaukee step-drills here:

Step Drill Bits | Drilling | Screwfix

Buy Step Drill Bits at Screwfix.com. Cone-shaped bit allows for the drilling of multiple holes without having to swap bits. Hundreds of stores nationwide.

www.screwfix.com

 

[pirate]

I have the Erbauer ones, and they are fine for light work, but when I bought mine a few years ago they were half the price shown, so prices have sure gone up.

 

[nicebutdim]

As an aside, check out the price for Milwaukee step-drills here:

Step Drill Bits | Drilling | Screwfix

Buy Step Drill Bits at Screwfix.com. Cone-shaped bit allows for the drilling of multiple holes without having to swap bits. Hundreds of stores nationwide.

www.screwfix.com

Seems the forum needs a 'shocked' emoji! I'm guessing they must be very good. While there nothing more useless than a poor quality step drill, £250 is a tad more expensive than one might expect to pay for good quality.

I have a small erbauer step drill. It's not up there with the best of them, but more than respectable for the price paid at the time. Treated with care they'll last quite well and certainly represent good value for money.

I think you've nailed the punch issue with the mention of time. While I like the idea of punches, I need to get stuff done quickly and efficiently and smooth cutting hole saws provide a decent compromise where it comes to making clean cuts quickly. If it came to fitting 50 loop in boxes to trunking, I'd be shown the door before punching a fraction of them.

 

[pirate]

Fair comment, @nicebutdim
Time is something of which I have plenty, but I fully realise that most guys don't have that luxury.
Just been helping a friend install CCTV and alarms and internet extenders...he hates what I do, I love what he does, but both retired so we just play about til we find a way we are both happy with and go for it!
His pet hate is my obsession with preventing premature collapse in the event of fire...but he goes with it, even though I may be slightly obsessive!
He knows his stuff though...I just install the cables!
We agonised for ages over gettin WiFi from the main building to a garage 50 metres away, but he came up with a mast on the main building and a receiver on the garage roof...we tweaked it for hours to get the best signal, then local lads kicked footballs against the garage mast and sent it askew...and it still works fine!
Variety...the spice of life!...and galvy band is your friend!

 

[pc1966]

The time aspect is a factor for many commercial sparks, but of course if you have to work on an existing installation you also have to consider time / risk of masking off stuff and hoovering out swarf afterwards.

@pirate raised an important advantage and that is a hole punch can often be used in areas where you can't get a hole saw + battery drill in to, and I would also add that a hole punch is very useful if you have an existing hole that is too small. Unlike a saw, you can open out a big hole without precise centring, moving it a bit to one side if wanted, etc.

A cone drill is handy as well as it can open out holes, but they remain centred by design, sometimes better/easier, occasionally not best result is you need to clear larger gland nut, etc.