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Hi i am curious I seem to have about this happen to me from time to time and it seems to be more on patches than on newly hung rock.

I will get a spot or to that lifts up. sometimes it doesnt lift up until paint. i usually cut into the side mud behind and re attatch and it seems to be fine.

I knew a guy who used to dampen his tape before he put it up. but I really dont care for doing that and had it lift up on me after doing this.


Just wondering if there were any tricks or something i could pay more attention to, to make this a problem of the past.


Thanks everyone.
 

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I'm curious too. DONT worry rockers, anything more than a small patch, I sub out.

But I have forever had the same problem and have listened, read, etc. with only slight improvement. (mud behind the tape, dont press it all out, don't overwork it, let it dry, etc.)

Any new tricks?
 

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For patch work i carry around a role of self stick mesh tape, it never lifts, GMOD
Gene, I've been using that too with pretty good results. However, it always requires just a little prouder application of mud. (I use 5 or 20 for the little bit I do). I would love to hear the "real secret" about applying tape without bubbling.

I'll bet the rockers are laughing at me.:surrender:
 

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I mainly do bathrooms so I do all my drywall work myself. After doing it for 20 years I still get the occassional spot.
I use Sheetrock 90 to tape and I think in my case its when the mud has set up too much and I'm trying to use it. I have tried dampening the paper - I think it helps, but it is a PITA.
I have also tried a perforated paper tape and found that it would tear in the corners and lift!

As I said, I only get a few here and there. I normally catch it on the next coat of mud, cut it out, and fill it.

If there is a secret for eliminating it altogether,....love to hear it!!
 

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I don't use paper tape on patches with quickset mud like 5 or 20, it sets too fast for the paper to absorb and bond. I will rarely use paper with 45 and 90 but it has to be on the wet side when you install it.

I sounds like your taping painted surfaces when patching. If so, the I recomend the use of mesh,not paper.

You will learn from your mistakes, sometimes the mesh will lift at the overlapping corners and you will learn how to apply it ''thinking'' about witch way you will be applying the mud. This will help.:thumbsup:
 

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Anytime you have to tape use Durabond 20 or 45 make sure it's the Brown bag not the white bag carp, anytime I have to tape I use Durabond if it's a whole room I use 90 if it's a patch I will use 45 or 20 I have not had a problem with paper tape lifting in 24 years. one of the guys I use to work for back in 1984 he calls me:notworthy The King of Durabond cause he has seen first hand what I do with Durabond. I always use Brown Bag Durabond20,45,90 I would put it up against any Product out there, even Plaster cause Durabond is Harder then Plaster.

ROCK ON TEDDLEY NUGENT
 

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Gene, I've been using that too with pretty good results. However, it always requires just a little prouder application of mud. (I use 5 or 20 for the little bit I do). I would love to hear the "real secret" about applying tape without bubbling.

I'll bet the rockers are laughing at me.:surrender:
Bubbling is the wrong term, they are BLISTERS,,,, (glad i got that straightened out)

Blisters are caused by no mud behind the tape, and they often (most the time) don't show up till you apply the next coat. If you are haveing trouble with blisters in the corners, you are most likely applying mud to one side, then when you are applying it to the other side, the SIDE of your knive is removeing some from the first side, leaving you with a blister, just check it out and make sure that is not the problem.
Another thing that causes them is wipeing ALL the mud out from under the tape (wipeing TOO hard)

You asked for the REAL SECRECT,,, okay here it is,,,,, make sure you have mud behind the tape,,, it really is that simple,,, not always easy, but real simple!!!

mesh???? we won't go there,,, I wouldn't use mesh on my mother-in-laws house,,, okay??
 

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Captain Sheetrock

Thanks!

Whenever I have had the opportunity to do corners, they always turn out fine. Thanks for the correction about blisters-seriously I hate to sound like a HO. It's kind of like when homeowners call a three way switch a two way switch in my main trade.:laughing:

The blisters I usually have come up are only where the gap between the sheets is larger. I usually level out the seams with 5, then do something else for awhile.

I later come back and embed the tape in a pretty generous layer of pre-mix or 20. I dont push too hard on the knife because I know you can actually squeeze all the useful mud out. But I still sometimes get blisters.

Your work is an art, and I stay away from it whenever possible, but sometimes I have to do a quick fix. I appreciate your insight.:notworthy
 

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Captain Sheetrock

Thanks!

Whenever I have had the opportunity to do corners, they always turn out fine. Thanks for the correction about blisters-seriously I hate to sound like a HO. It's kind of like when homeowners call a three way switch a two way switch in my main trade.:laughing:

The blisters I usually have come up are only where the gap between the sheets is larger. I usually level out the seams with 5, then do something else for awhile.

I later come back and embed the tape in a pretty generous layer of pre-mix or 20. I dont push too hard on the knife because I know you can actually squeeze all the useful mud out. But I still sometimes get blisters.

Your work is an art, and I stay away from it whenever possible, but sometimes I have to do a quick fix. I appreciate your insight.:notworthy

Try this,,, when I have a job where there are large "gaps", I mix some 20 min and pre-fill em, then I go about getting all my stuff unloaded and set=up, letting the 20 set,,, then tape. When your doing this sort of thing, you HAVE to let the pre-fill mud SET,, or your just pissing in the wind (Bob Dylan song). Here's another thing,, if you don't do it all the time, be sure and use a "soft, flexible" 5 or 6 (actully I'd recommend an 8") to wipe the tape,,,, I use a stiff knife, but I do know what I'm doing,,,, a soft one will give you a break, if you are unsure about how HARD to wipe.

That brings up another point,,, (cause I have had a few glasses of homebrew,,, I call it Obama-beer, but thats another thread!!) If you are not doing this all the time,,, PLEASE use "soft, flexible, blue steel knives" Stainless knives are great, in that they don't rust, but they are VERY UNFORGIVING and you need to use them ONLY after you know what your doing!!!

nuff said
 

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Try this,,, when I have a job where there are large "gaps", I mix some 20 min and pre-fill em, then I go about getting all my stuff unloaded and set=up, letting the 20 set,,, then tape. When your doing this sort of thing, you HAVE to let the pre-fill mud SET,, or your just pissing in the wind (Bob Dylan song). Here's another thing,, if you don't do it all the time, be sure and use a "soft, flexible" 5 or 6 (actully I'd recommend an 8") to wipe the tape,,,, I use a stiff knife, but I do know what I'm doing,,,, a soft one will give you a break, if you are unsure about how HARD to wipe.

That brings up another point,,, (cause I have had a few glasses of homebrew,,, I call it Obama-beer, but thats another thread!!) If you are not doing this all the time,,, PLEASE use "soft, flexible, blue steel knives" Stainless knives are great, in that they don't rust, but they are VERY UNFORGIVING and you need to use them ONLY after you know what your doing!!!

nuff said
Thanks for the tips. One question I am unclear about-probably a trade specific term, and I will show my stupidity here and now.

When you refer to a soft knife, is that a plastic cheapo?

What kind of home brew-I'm THIRSTY!:drink:
 

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If I only have some patching to do, here it is - make a donut of regular mud ( I only use "machine mud" ) on your hawk. Then put some water inside the donut. Add to the water quick set plaster. Mix the plaster, then mix it into the regular mud.

When you apply this, it will finish like plaster does - no sanding required. It will 'go off' in about 15 minutes, depending on the mix proportions. I mix about 50/50.

When it starts to 'go off ' trowel it smooth. Think of it the same as finishing concrete, you need to be on it at the right time. With a little practice you will be doing those repairs in one coat, done.

ps. I had to practically strangle my plasterer 30yrs ago to get him to show me this trick. So don't be telling the hacks about this, please.

Enjoy :clap:
 

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I'll put in my 2cents here...

Setting compound can act like concrete in that if it dries/sets without enough moisture it will be weak and crumbly. When you tape with it and leave only a thin to no layer underneath - the tape will wick the moisture out of it and the mud will set without enough -> go all powdery -> no bond -> blisters. To keep this from happening; never wipe too hard, and top coat the tape immediately. By embedding the tape like this there will be less chance of it drying out and being weak. Has worked for me!

D'S
 

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Thanks for the tips. One question I am unclear about-probably a trade specific term, and I will show my stupidity here and now.

When you refer to a soft knife, is that a plastic cheapo?

What kind of home brew-I'm THIRSTY!:drink:
What I mean about a soft knife, is one that is "flexible",,, blue steel knives are "flimsier than stainless ones". If you buy a stainless, (specially from Blowes Or Homeless Depot) They have a shorter blade making it EVEN stiffer than a PRO stainless.

Just put the knive against the wall, and push it(with your index), does it bow in the middle, if not its stiff,,,

And the homebrew???? I call it Obama-beer, cause ,,,, well ya know,,, the economy,,, its $6 for 6 gallons,, its 9 1/2% alc,,, taste like a Bartles and James wine cooler.
 

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I'll put in my 2cents here...

Setting compound can act like concrete in that if it dries/sets without enough moisture it will be weak and crumbly. When you tape with it and leave only a thin to no layer underneath - the tape will wick the moisture out of it and the mud will set without enough -> go all powdery -> no bond -> blisters. To keep this from happening; never wipe too hard, and top coat the tape immediately. By embedding the tape like this there will be less chance of it drying out and being weak. Has worked for me!

D'S

Good point, when I tape with "hot mud" I always, run over it again, as I am tapeing it,,,
 
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