What size channeling chisel?

[vv2806]

I've been looking for a drill attachment to chisel the walls for cables. Many people here recommend the Armeg SDS+ chisel. My question is - do I need both 30mm and 20mm?

The Screwfix catalogue description is that 30mm is for installing cables and wires and 20mm extended version is for gaining access behind skirting board. But if the channel behind the skirting is only 20mm, what is the point to have it wider above the skirting? Should I buy only the 20mm chisel? Is it possible to rut it twice if a wider channel is needed?

 

[xerxes]

You will need the channel to be wider than 20mm if you're using capping to cover the cable, or oval conduit wider than 16mm. However, the chisel will not cut a precise width: the result will probably be a little wider than the size of the chisel.

But it's easy enough to use a flat chisel, or a bolster, to widen an existing channel, and probably not worth the expense of buying both widths of channeling chisel if you have only a small amount of work to do.

 

[vv2806]

Thank you! 20 mm chisel would do then. Best wishes for the New Year!

 

[xerxes]

All the best to you, too.