A couple of plastering questions

[AJ]

I'm trying to learn, so these might be pretty daft..

1) On fresh plasterboard, I think I'm supposed to tape over the gaps between boards, and internal corners. What's better to use ... the 'paper' tape, or the slightly-sticky mesh stuff? And how to secure it? A bit of plaster underneath? Or wet it? Or filler in the gap, then the paper tape, then let it dry? Or just press it on and hope. (First attempt -> it fell off!)

2) How many coats over fresh plasterboard? Thistle multi-finish seems to work OK.. Should it be 1 coat then dry a bit then polish, or 1 rougher coat then dry a bit then another coat then dry a bit more then polish? What tends to work best?

Cheers!

[Steven Campbell]

is a great source of information.

is the tape my plasterers used when I had some work done. It is self adhesive so sticks to the plasterboard.

Steven.

[Andrew Gabriel]

Mesh tape, scrim tape.

Smear plaster along it with the trowel, and it will go through the holes and hold it.

Two coats. On plasterboard, if the first coat seems to have gone on particularly well, I might decide to polish it up as the final coat, but I always start with the intention of two coats.

You put the second coat on when first has almost or just set, but whilst it's still wet. If it dries, you have to treat as for a reskim (i.e. PVA before second coat). Setting and drying are quite different -- it needs to be wet to set (will go darker), and it dries out afterwards (will go back ligher).

It's slightly self adhesive when the roll is new, but after it's been around plaster dust, it's not anymore. Doesn't matter anyway -- just smear plaster down it and it will stick. (Didn't used to be self adhesive anyway.)

[George]

Fill the gap first with builders caulk then apply tape over filled gaps. This helps to reduce hairline cracks later on after the plaster has dried.

The thicker the coat on first application the better,again this reduces the risk of hairline fractures appearing.

[sm_jamieson]

For what its worth, none of the plasterers I have had have ever done 2 coats on plasterboard, and get a perfectly good finish. I board and tape for them (no gaps between board, mesh tape). Simon.

[Lobster]

Yes, the adhesive is only to hold the tape in place for convenience while applying it, ie for as long as it takes to cover over with plaster.

David

[Fred]

Slightly OT because I've never had any luck plastering but if you wish to put plasterboards up and not plaster them, what is the best way to disguise the joins between them? I think there is a special tape to cover the join but I'm not sure what it is called. The only tapes I have found are the ones mentioned here that are non-adhesive or have raised patterns. These may be great when you are plastering on top but are not suitable when you are painting the naked board.