Stuck brass compression fittings

Assuming it's a normal sized one, it will have no trouble with the correct disk. (I have a rechargeable the size of a highlighter pen, that has limited "oomph").

Even the cordless Lidl one, which has a bit less torque than a mains one, will happily cut mild or stainless steel (I trimmed some M5 stainless machine screws with it yesterday). Brass, like aluminium, has a tendency to clog abrasive wheels but it works fine if you use the right speed and pressure. As I said, I'd recommend the thicker fibre reinforced sort. They cut slower than the thinner non reinforced type because they have to remove more metal, but the latter wear out faster and it's easy to break them.

Although they can still "round off" nuts, DAMHIK!

This is an occasion where an angle grinder isn't the best answer. So use its elder brother - a large hammer. 'Shocking' a nut free is often better than just applying more force.

I have to proceed with care because the other side of the isolators go into PVC push fit rightangle connectors tight up against the wall where the pipes enter. If I break one of those I'll be without water because the pipes come through the wall from behind the kitchen base units.

If that is an option dont faff about unscrewing it - just get a pipe cutter as close as possible and truncate it

Sure, if there is room. I'd still argue that separating the compression fitting as a start keeps the most options open.

Use a junior hacksaw at 45 deg. to cut the olive until it's almost through (the angle avoids cutting the pipe), insert screwdriver and twist - olive is gone. Use new olive in same place as the old one.

If it?s been wellied up really tight though the pipe will be ?waisted? and it?s unlikely a new olive will seal in the same position. Better to trim the pipe and fit the olive to an un-squished bit of pipe.

Tim

Thinking ahead - well done ****