20mm holesaw Vs 20mm punch

[RF Lighting]

Not wanting to hijack Steve's mains change thread any more than we already have, I though it best to start a new topic.

I've done a couple of holes for you to compare.

The first ones are in the side of an old fluorescent light fitting to show that it does not distort the surrounding area even with really thin metal.

Holesaw on the left, punch on the right

Holesaw

Punch



I also punched a hole through some unistrut. It's 2.5mm thick steel, just to show it can.

 

[ban-all-sheds]

Wanna use the holesaw on the unistrut?

 

[333rocky333]

I would say the punch hole is better and closer to 20 mm.
I find holesaws tend to cut larger if your too heavy handed.
Can you stick a bit of plastic conduit in the hole

 

[Steve]

Wanna use the holesaw on the unistrut?

Dont make him get his big tool out again lol

 

[Lectrician]

Is this the one you have RF?

What size pilot is yours?

 

[RF Lighting]

Wanna use the holesaw on the unistrut?

You'll have to wait until tomorrow.

I just tried.

FFS

 

[RF Lighting]

Is this the one you have RF?

What size pilot is yours?

I have this one

RS part number 477-8779

It is a 10mm pilot hole

 

[ban-all-sheds]

Oh dear.

Still - I think it shows what a good job it was starting out to do...

 

[RF Lighting]

I'll get a new pilot bit tomorrow and try again

 

[electronicsuk]

I was intrigued when I read about these on the 'other' thread, and having seen the results, it seems like a set of these punches would be handy to have. When looking at the Q-Max punches I read that for larger holes, the punch does not require a die nut. Are the larger models self-tapping into the pilot hole?

 

[crystal ball]

These punches are just the job for opening out 20mm to 25mm/32mm

I have used them for years, I think mine came from CPC

 

[fattony]

mmm Im tempted and surprised they go through unistrut.

Good work RF

 

[Lectrician]

I must admit, I didn't think it would be any good on UNI - Do you use it often on UNI RF? I can't imagine it would last too long if you did?

10mm pilot is fair sized hole. You would likely need to pilot drill for the 10mm, especially if getting it aligned perfectly was important. So thats 3 holes to make....A holesaw would be quicker, but the punch far neater.

I did work experience with an electrical company that also had a motor rewind and panel building shop. They used to have hydraulic punches which where similar in operation, they used them for punching the 22mm holes for the indicators and controls, and for larger holes for panel meters etc.

I may get myself one to remind myself what they are like to use (wish you posted this earlier yesterday as I ordered a lod of bits from RS for an upcoming job yesterday morning....)

 

[vsynth]

I always use a Q-Max punch if I can, we have some 80mm ones at work for cutting out a hole for a cabinet fan...much less messy/noisy and a superior result.

They even do square/rectangular ones for panel meters etc.

 

[ericmark]

Top marks for photos. Bet that wasn't a camera-phone? Hard to light reflective services like that too. Also impressed with punches. Have used for panel work found hole saw not accurate enough so either 20mm instead of 22mm and file or punch. No contest.

But for glands etc will admit hole saw is faster. Unless you break or bend pilot drill and the only people who don't from time to time bend or brake drill have got others to do drilling for them.