Advise on hole cutting - steel consumer unit

[scanner]

Hello,

I'm installing a new consumer unit in my flat for one of my Part P qualifying jobs.

It's a concrete building with all the wiring in conduit and MICC.

I've got a new steel Wilex CU which has various round knock-outs for the cabling, but a few of them don't line up with the existing conduit etc.... some line up half on / half off the knock outs.

Does anyone know of a tried and tested way of hole cutting across knock outs without "knocking them out".

Also can anyone recommend a good set of hole cutters (metric and imperial) for the job.

Any advise would be greatly appreciated,

Thanks,

Al

 

[UNG]

Clamp 2 pieces of wood 1 inside and 1 outside of the box and use a hole saw to drill through the wood and box where you need the holes ( no need to drill through the wood inside the box that provides support to the knock outs)

I use Starrett holesaws not cheap but they outlast others I've used

 

[scanner]

Genius !

Thanks UNG...

I'm off to buy some clamps and some hole saws.

Have a good day !

Al

 

[UNG]

Good to see someone is happy, glad I could help

 

[ian.settle1]

You may have a problem as some knockouts which have 2 small pieces of metal holding knockout to the CU, drill them out and knockout will come out as well.

You would therefore have to put a metal plate acoss the top on the outside of CU.

 

[UNG]

Thats why you clamp the wood in place to stop the holesaw ripping the knockouts out

 

[wattsup]

various methods, I usually fix 2 x 2 galv / plastic / trunkings under/side/top. bush through to existing knockouts, spacing locknut between

 

[Des 56]

various methods, I usually fix 2 x 2 galv / plastic / trunkings under/side/top. bush through to existing knockouts, spacing locknut between

This is the method I have seen countless times and advise to use
Depending on the spacing and quantity of the conduits coming through the top,try and pick these up directly,fit 2x2 galv trunking underneath,drilling holes to suit the pipes and the dist board ,bush and locknut with a locknut between to keep the board and the trunking slightly apart

 

[bugsy]

I'd also go with a length of trunking, having said that I've never tried the other method

 

[ian.settle1]

Thats why you clamp the wood in place to stop the holesaw ripping the knockouts out

What I was refering to was not ripping the knockout out but when the hole is cut and the hole cut happens overlap the part of the knockout which is attached to the CU the knockout will come out