cutting holes in an RSJ for services. Anyone cracked this?

[brumylad]

cutting holes in an RSJ for cable runs. Anyone cracked this nut ?

I've done it using the drill lots of overlaping holes method; using a jisaw with metal blade on horizontal cut; and 4" angle grinder with carbarundum metal cutting disc (4 cutts).

the latest job needed 4 holes cutting so after spending so long lying on my belly nursing various overheating power tools I'm motivated to ask for ideas from others right now!

 

[Lectrician]

I would firstly never even attempt it unless authorised to do so by the structural engineer.

One the rare occasions I have, it has been when a plumber also needs to run through, and then, we get a steel works guy in to do the job

You an usually manage to get cables in over the beam in my experience?

 

[Lower]

have you ever tried a mag drill with a hole saw? Don't know how well it would work on site but we use that method for cutting holes in up to 12mm webs in rsj's on a regular basis.

 

[tim-spam]

Yes, a good quality hole saw should do the job neatly - it is a good idea to keep it well lubricated with oil, and allow it to cool occasionally. In terms of it's acceptability, if the hole size is no more than around 30mm maximum (assuming the RSJ is around 250+mm deep), and drilled on the neutral axis, the reduction in the 'I' value will be minimal.

 

[FabianBom]

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