On Sun, 9 Aug 2020 01:58:46 +0100, John Rumm
wrote:

snip

And that's the thing. Ok, I've done a fireplace where I've removed a
surround and hearth and re-rendered then plastered the chimney breast
etc but not a whole wall and certainly not a ceiling.

Oddly the first thing I ever skimmed was a ceiling. It turns out it was
not that much different from doing a wall (I figured if I could hack a
ceiling the walls ought to be "downhill" from there.

;-)

In this place there seem to be three layers, a sand-cement render, a
rough plaster and finer skim? Because it's a Victorian 'Workers
Cottage' (or just typical of the tolerances in play in general at the
time) that combo can range from near nothing to over an inch thick.

(Although I made very slow progress, and had to do it in two halves.
Needed a bit of sanding where the halves met)

Still sound like a great first go.

Unlike the physical bit of wiring, plumbing, tiling, carpentry and
small bits of brickwork where you can generally read up and then do a
reasonable job, plastering really is an art.

Like many such things, it improves with practice.

Sure, but unlike say wiring, plumbing or basic carpentry where it's
really a matter of seeing how it's done and duplicating that process,
there are so many variables with full rendering / plastering (maybe
not so much with skimming) that any one not being right is likely to
cause big issues.

Like, even if you get the cement render on, is it shallow / flat
enough to allow for the plaster layer ... and that's ignoring keeping
it all plumb!

The render isn't so bad, once you know what constitutes the right
consistency as you can generally run a straight edge over it as it's
going off slightly and it doesn't matter about the actual finish.

I normally find I am
getting "ok" just as the job is about over :-)

Yup, till you have done enough of it like some of your woodwork you
have shared here. ;-)

But I understand that even with that, if you are doing a particular
piece for the first time that you wouldn't guarantee you wouldn't make
mistakes, simply because it's often easier to make a mistake than not
(even cutting the wrong side of a line, making an error in the
measuring maths etc).

Cheers, T i m