prepping and between coat drywall grits

duburban

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used 120 on my dts400 today to sand the area around a patch for adhesion and it came out dangerously smooth. what grits do you guys use before, between and to finish drywall?
 
thanks. i was going to try that series next. this dts is really exciting for drywall but need to pair it with a mini/midi for portability.
 
dont go too high in the grits or the filler will be smoother than the slab adn show up in the paint
 
I know this isn't going to sound good but someone has to say it.
If you are using multiple grits to sand drywall patching ... you need to learn how to tape better. A good tape and mud job does not need multiple sanding steps, only 1 final sanding at the end to provide a uniform surface.
I used to sand 100 or 120, since using the ets 125, I've gone to 120 or 150. Don't be afraid to just run the sander across the natural drywall surface. You don't have to sand the drywall, just run the sander across the surface. This helps make the drywall and taped areas more uniform.
 
i was curious about a grit adequate to clean and rough the surface and a grit to sand the mud. i don't do a lot of drywall though, i'm always trying to learn how to do it better.
 
Holzhacker said:
I know this isn't going to sound good but someone has to say it.
If you are using multiple grits to sand drywall patching ... you need to learn how to tape better. A good tape and mud job does not need multiple sanding steps, only 1 final sanding at the end to provide a uniform surface.
I used to sand 100 or 120, since using the ets 125, I've gone to 120 or 150. Don't be afraid to just run the sander across the natural drywall surface. You don't have to sand the drywall, just run the sander across the surface. This helps make the drywall and taped areas more uniform.

no ofense taken. im no expert on tape and jointing.
i only use 60 grit on the very rare ocasion where there is too much filler . i sand with 80 grit because it is faster that 120 g , then a final rub with 120 g  to give it a smooth  finish.
iv never seen any taping and jointing (not seen any experts do it thow ,adn over here we raraly use tape and jointing)  done good enough that it didnt need a lot of sanding

maybe i could learn a few things off of you if your wiling to share
 
we only ever do it in situations where we couldnt use skim or the mess it creates.
we use festool sanders and vacs and have a big fan that pulls anyother dust out side through a big pipe.
 
On almost all jobs I'm on its done. Anytime I put up metal stud walls and ceilings they are always taped and joined. It's a skill that takes lots if practice. Less filler is more due to how slow it flipping drys. Usually end up using three coats to get the desired finish
 
its terable stuff to use. you could leave a bucket open for 6 months and it wouldnt be solid the whole way through.
the trick is to use thin layers.
 
I do alot of tape repair and cosmetics. Its pretty much 150 across the board. Anything lower furs up the gwb paper. I do alot of it with the ets150 and the dts. It is very effective although slow on larger scales.
 
Ya Alan it's horrible stuff. It's feckin messy as well. Gets all over the place. I totaly refuse to do it caus I havnt had enough practice at it. I even make the guy I sub work off do it and hes not great at it either or get someone to do it  [tongue]
 
i had to fix a ceiling in a hall (no skrim only that hessan stuff) i re screwed adn scraped out the joints and filled everything with filler. i used 3 buckets on that ceiling and got 1.5 bags out of my ct22. . total nightmare. the place was still distroyed in dust.
the problem is that it schrinks as it dries and needs another coat to make it flush so people over do it to compensate
 
The average repair is 3-4 skims, after bedding the tape.
 
It sure is a skill refined over time, a few things I have learned over time.

Heavyweight compound for first coat, start with the flat joints, spread compound, bed tape, apply more compound over and smooth, all with a 6" taping knife. Then do the same for all the corners using both a corner tool and 6" knife.

Let dry, use a dehumidifier to help speed the process.

Scrape with 6" knife (I usually don't sand after first coat), lightweight compound for second coat using a 10" knife and corner tool.

Dry.

Scrape with knife then sand with 150 grit, mark areas that need another coat. Recoat, dry, sand, done.

Some general notes.
On most jobs I can get away with only two coats on 75% of the areas,
When using the premixed compound I almost always add some water and remix,
If I am doing small areas or need to speed the job along I will use the quick set powdered compounds, 5, 30, 45 minute.
I also find that older knifes work better then brand new ones, the metal seems to soften and the edges get nice and sharp to give a smooth finish.

Oh, and keep your tools clean, constantly scrape them off while working [wink]
 
Like Dean I have never seen any one tape seal the joints.       Always fully plastered wall.        Reading wa has been said about the tape n joint method sounds more hassle than plastering.    Get no dust with plastering  you mix out side.    Im not brilliant at plastering and can only do walls and if im carefull I dont make any mess at all a good plasterer can make hardly any mess even when doing ceilings.  

JMB
 
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