OT: Is anyone here a "builder" need advice

sweetjesus · Post by **sweetjesus** » Thu Dec 22, 2005 7:06 am

I need to know a bit more about sealing drywall/plasterboard joints after they have been attached to wall studs and preparping the surface for painting.

i have used base coat plaster to seal the seams of the sheets and i need to know more about applying the top coat.

1) do i have to sand the basecoat (which also has drywall/gyprock tape) first before applying the topcoat? if so, can i use a soft electric sander, or should i use a hand sander?

2) how to use cornering cement?

Many thanks
SJ the builder

borg · Post by **borg** » Thu Dec 22, 2005 10:56 am

1) you can use a machine (the small ones), but don't use sandpaper. there is a special thingie for this. don't know how to explain. it's a sheet of waffled 'cloth', like a fly/mosquito screen, but harder. you have them in different 'hardness' for in between layers and finishing.

don't understand 2)

martin808 · Post by **martin808** » Thu Dec 22, 2005 5:46 pm

hi. I'm a builder/joiner.

1)sanding the first coat is only needed if the plaster is sitting proud of the plasterboard. you can use an electric sander but i always use a sanding pole. always wear a dust mask when sanding that shit. I'ts a horrible job because the dust gets everywhere.

2) to do the corners, apply mesh tape into the corner then do one side of the corner, leave it to set then apply the plaster on the other side if your trying to do the whole corner at once you'll end up in a mess.

hope that helps. if you need anymore info just ask.

cant beleive i just answered a builder question on the ableton site.

sweetjesus · Post by **sweetjesus** » Thu Dec 22, 2005 6:09 pm

martin808 wrote:hi. I'm a builder/joiner.

1)sanding the first coat is only needed if the plaster is sitting proud of the plasterboard. you can use an electric sander but i always use a sanding pole. always wear a dust mask when sanding that shit. I'ts a horrible job because the dust gets everywhere.

2) to do the corners, apply mesh tape into the corner then do one side of the corner, leave it to set then apply the plaster on the other side if your trying to do the whole corner at once you'll end up in a mess.

hope that helps. if you need anymore info just ask.

cant beleive i just answered a builder question on the ableton site.

Thanks Borg & Martin808, i'm very confident now I have read your responses. I will check out the stuff you talk about for my electric sander Borg.

Sorry to have muddled your worlds of beats and plaster Martin808!

I do have one more question about your response Martin, you mean that the mesh tape doesnt actually fold on a 90 degree angle in the insid corner.. two pieces get applied, one to each side of the drywall right?

I'm not sure how this links up with what I'm doing because I will be getting some kind of thin aluminium delivered which will go into the corners and i have cornering cement to use with it.

Just as an offtopic for folks out there doing building, one thing I've realised having worked with some builders of different backgrounds on this project is that everywhere in the world has very unique building techniques, not to be confused with architecture differences.

DeadlyKungFu · Post by **DeadlyKungFu** » Thu Dec 22, 2005 6:14 pm

martin808 wrote:cant beleive i just answered a builder question on the ableton site.

balance must be maintained...
http://forum.doityourself.com/showthrea ... post901794

serotoninsteve · Post by **serotoninsteve** » Thu Dec 22, 2005 6:17 pm

martin808 wrote: 2) to do the corners, apply mesh tape into the corner then do one side of the corner, leave it to set then apply the plaster on the other side if your trying to do the whole corner at once you'll end up in a mess.

There is also a better cornering cement (about double the price) wich already contains fiberglass. With this one you don´t have to mess with the mesh tape.
Usually it depends on the model of your board (thinner at the corners) if mesh tape is used or not. With the right tools it is not that hard to do.

Greetings

serotoninsteve · Post by **serotoninsteve** » Thu Dec 22, 2005 6:26 pm

sweetjesus wrote:
I'm not sure how this links up with what I'm doing because I will be getting some kind of thin aluminium delivered which will go into the corners and i have cornering cement to use with it.

If it´s rectangular aluminium with holes, they are for outside corners then, I never used on inside corners.

Greetings

martin808 · Post by **martin808** » Thu Dec 22, 2005 6:28 pm

sweetjesus wrote:Sorry to have muddled your worlds of beats and plaster Martin808!

thats ok. I'm just home and i've still got my work head on

sweetjesus wrote: I do have one more question about your response Martin, you mean that the mesh tape doesnt actually fold on a 90 degree angle in the insid corner.. two pieces get applied, one to each side of the drywall right?

no, the tape must be folded at 90 degrees. to hold the corner together. the plaster will crack otherwise. if you are getting the aluminium stuff then thats ok but i generally use that for external corners...or is that what you meant. I was thinking of internal corners.

also, i dont know where you are and if you can get it but there's stuff you can get called 'velvet' made by lafarge its very easy to sand and leaves a silky finish. its really expensive though. about £20 a small bag compared to about £5 for the ordinary joint filler.

martin808 · Post by **martin808** » Thu Dec 22, 2005 6:34 pm

DeadlyKungFu wrote:
martin808 wrote:cant beleive i just answered a builder question on the ableton site.
balance must be maintained...
http://forum.doityourself.com/showthrea ... post901794

thats hilarious. hope you get a reply.

sweetjesus · Post by **sweetjesus** » Thu Dec 22, 2005 6:35 pm

serotoninsteve wrote:
martin808 wrote: 2) to do the corners, apply mesh tape into the corner then do one side of the corner, leave it to set then apply the plaster on the other side if your trying to do the whole corner at once you'll end up in a mess.
There is also a better cornering cement (about double the price) wich already contains fiberglass. With this one you don´t have to mess with the mesh tape.
Usually it depends on the model of your board (thinner at the corners) if mesh tape is used or not. With the right tools it is not that hard to do.

Greetings

not so afraid of handling mesh tape, been using it on seams without any troubles, think i will use it on the corners.

found out more info about cornice too.

just after i got all this wicked advice from you guys, i got access to this PDF
http://www.gyprock.com.au/technical/diy ... 4CE598.pdf

which helps me visualise what you guys are saying.

on xmas day .. guess who's going to be preparing his walls for painting? *GRIN*

sweetjesus · Post by **sweetjesus** » Thu Dec 22, 2005 6:37 pm

martin808 wrote:
DeadlyKungFu wrote:
martin808 wrote:cant beleive i just answered a builder question on the ableton site.
balance must be maintained...
http://forum.doityourself.com/showthrea ... post901794

thats hilarious. hope you get a reply.

hhahahahahaha

man, you made my day! no.. you made my year with that little move of yours!

Machinate · Post by **Machinate** » Thu Dec 22, 2005 6:42 pm

DeadlyKungFu wrote:
martin808 wrote:cant beleive i just answered a builder question on the ableton site.
balance must be maintained...
http://forum.doityourself.com/showthrea ... post901794

Stunt of the year man, very nice! *giggle*

I told my wife though... .she didn't get it

mike holiday · Post by **mike holiday** » Thu Dec 22, 2005 7:09 pm

i recormed using metal corners for your corners, they make them .. just like for outside corners..

yuk, i sheetrocked a whole house i was living in, just me and a friend
do the screew holes good also other wise they'll show through the paint over time

DeadlyKungFu · Post by **DeadlyKungFu** » Thu Dec 22, 2005 7:23 pm

Something had to be done, I'm just killing time during the most pointless day at work of the year.

No replies yet, I guess the box would be good for spreading the plaster and you can play some beats to stay motivated.

David · Post by **David** » Thu Dec 22, 2005 7:25 pm

Cool thread

You basically want to measure out your piece of corner tape first so its the same length as the height of your wall, then fold the corner tape down the middle seam (there should be a slight seam running down the paper tapes middle). Then you can apply Fast Set (Filler) to both sides of the wall corner (2 to 3"), not too much and not too little. Then you push your corner tape into the corner of the wall, so the folded seam goes right into the corner. And puch the sides of the corner tape against the wall edges, carefully. Then using a 4" filling knife (kinda like a scraper except more bendy) and you want to start at the top and run your filling knife down the paper so it pushes it solidly against the wall and squeezes out the excess filler. That way you get the paper tape firmly in place. Then you want to skim over the top of the tape with filler to seal it off, obviously not leaving a big edge, it has to be nice and smooth. There should be a slight indentation on the plaster boards edge designed exactly for that purpose i.e. so you can fill in to it.

Like martin808 said then you can use a smoother filler like Velvet (ah the memories) to finish it off. It may take a couple of skims of velvet.

The aluminium tape is used for external corners.for the seams we used to use a mesh tape, cant remember its name though and its annoying me!

Good luck with your diy, post some pics of the finish if you can.