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Andrew Gabriel

In article . com,
writes:
As a mostly self-taught plasterer, I'm never absolutely certain as to
what extent my mixing proportions of plaster:water are correct. Most
times the mix is Ok but at other times it ends up too stiff. Could
someone please advise so that I can do some calibration?

What I'd appreciate knowing are optimum volume (litres) and weight
(Kg) of plaster per (say) 5 litres of water for

(1) British Gypsum Thistle Multifinish plaster

(2) Thistle Bonding Coat

Both litres and Kg would be appreciated as a cross check.

I've checked the BG web site but couldn't see anything relevant.

That's because no one mixes it up that way.
You start with a clean bucket, and fill it no more than 1/4
full of clean water. You then keep pouring in plaster and
mixing until you get the right consistency (and no lumps).

For bonding coat mixed up correctly, it will stay on the
trowel (just) when you turn the trowel vertically, but
will slide off if you give a small jerk. Finish coat is
more sloppy, and should slide off the trowel when you
hold it vertical. People who haven't done much plasting
usually mix it up much too stiff, thinking it will run
off the wall otherwise, but it doesn't.

--
Andrew Gabriel
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