A lot of the time mortar can make it's way into the channels from the bottom of the channel, and the very top, I've seen it mounded up at both points before now.
Normally I'll knock this out with a scutching chisel and most of the time the channel is clear.
Though locating the channel at mid...
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If it's a stud wall you could screw a...
Overhead?
If the SWA cable was steel armored, I have pulled an extremely long cable out of the ground with a mini digger.
The problem would be connecting the new cable to the old cable so it could be pulled through without breaking.
You can make a good connection between the L/N/E but that...
Ps, just for reference , If you see any watermains people, (not going to mention names) but the guys digging up the watermains.
It's worth chatting to them because they'll mole it for you, a lot cheaper and quicker than you think.
Could save you thousands and the peeps a lot of anxiety.
https://www.speedyservices.com/hire/moling-equipment
https://moleutilities.co.uk/what-we-do/impact-moling/
It's a bit like plumbing, you get a feel for it.
I use the same method, tighten up gently making sure no cross threading is taking place, then give it another tweak, and a final tweak before fixing in place.
Usually the third tweak produces nothing in the tightening procedure but gives peace...
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