Hi all
Further to a question I posted yesterday regarding using hex head bolts to fix steel trunking to unistrut, some others used dome head gutter bolts instead. These are presumably used so that they potentially damage the cables less than a hex head bolt. Following on from this, what type of screws do others use when fixing steel trunking for example to a block wall. Would you opt for countersunk or panhead screws? Different contractors I have worked with use both and I must admit that on larger steel trunking, the odd red rawlplug occasionally along its length doesn’t fill me with much confidence when the trunking could potentially be full of cable which would be quite a weight. On a recent job with steel trunking I used frame fixings( some call them concrete screws). Basically screws into a predrilled hole in the clockwork and has a countersunk torx head, no rawlplug required.I used these with a large flat washer and it took a great gold but I suppose my question remains are countersunk or panhead screws best (or specified) for fixing trunking or other accessories containing cable?
thanks