Advise on hole cutting - steel consumer unit

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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

 

[elektrisien]

You should ideally weld the knockouts shut, grind them down to ensure a smooth surface, then you can drill new holes as and where needed.