# butt joints. please help



## canadianwhite (Sep 13, 2010)

when i come to sanding on the butt joints i seem to have a cress down the middle of the joint why is this? first i mud over the tape (fiber)next coat go ether side of the joint. then finally i skim over the hole joint. but when i sand i have the cress. it feels smooth but some times i can feel a little bump. please help. thanks


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## Sir Mixalot (Jan 6, 2008)

Are you using premix mud?
How much of a gap on the butt joint before taping?


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## canadianwhite (Sep 13, 2010)

there is no gap or if there is it is not big. should there be? i use fast set for the first 2 coats


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## griz (Nov 26, 2009)

Not enough mud, too much sanding or both.:furious:


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## canadianwhite (Sep 13, 2010)

all othere joints are fine and there seems to be enough mud. it does not happen on every single 1 but most.


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## J F (Dec 3, 2005)

I spent 5 minutes and about 20 searches lookin' for a pic of a doobie stuck in some butt-cheeks, to no avail...nuttin'...who woulda thunk? :laughing:


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## A. Spruce (Aug 6, 2010)

canadianwhite said:


> when i come to sanding on the butt joints i seem to have a cress down the middle of the joint why is this? first i mud over the tape (fiber)next coat go ether side of the joint. then finally i skim over the hole joint. but when i sand i have the cress. it feels smooth but some times i can feel a little bump. please help. thanks


You're not using the right kind of butt tape! It really does make all the difference.


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## Sir Mixalot (Jan 6, 2008)

Sounds like maybe oversanding in the middle of the butt.:whistling
I trim the fibertape in the middle between coats. 
Then when sanding, one swipe down the middle. 
Then feather the rest.:thumbsup:


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## Rob PA (Aug 30, 2010)

sounds like a sanding issue or not enough of a feather out to conceal the joint


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## oldrivers (May 6, 2007)

use paper tape .


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## 2buckcanuck (Jul 7, 2010)

one drop the mesh tape,did the rockers "V" the butt joint,if not they should.you do it to get rid of the loose paper,examine the end of a sheet of drywall that is new,you will notice the paper is loose on the rock.you shave it off with a sharp knife.even usg recommends doing this.in laymen terms,paper dont stick to nothing unless there is glue (mud) under it.thats why the dead middle of you butts are creasting


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## SAW.co (Jan 2, 2011)

A. Spruce said:


> You're not using the right kind of butt tape! It really does make all the difference.


I think thats ME:jester:


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## Big Shoe (Jun 16, 2008)

A. Spruce said:


> You're not using the right kind of butt tape! It really does make all the difference.


 We need to show this fix on the plumbers forum.:laughing:


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## Willy is (May 20, 2010)

I assume that the drywall joint you are talking about is running vertically; up and down?

If the studs are not perfectly in line, if the stud is sticking out a bit it would make your problem worse.

On occasion I have either planed or ground down a stud that is sticking out _proud_ of the alignment of the others.

Poor stud alignment can also work in reverse; if the studs on either side of the stud that you joint will fall on are low it will create a similar problem. You can use drywall shims to fix these low spots if they exist or rip shims as needed to the correct space needed.

I don't know if that could be part of your problem but before installing DW it is worth checking the wall with a good straight edge.

Willy


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## Terrorron (Nov 7, 2008)

Willy is said:


> I assume that the drywall joint you are talking about is running vertically; up and down?
> 
> If the studs are not perfectly in line, if the stud is sticking out a bit it would make your problem worse.
> 
> ...


In a non-bearing wall, an easier fix is to cut the offending stud on the bowed (convex) side, with the blade in your skilsaw laid over. Toe nail through to close the kerf...repeat as required. Slightly "hack" I know, but it's less "hack" than just boarding right over it...

Cheers, Ron


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## 2buckcanuck (Jul 7, 2010)

Willy is said:


> I assume that the drywall joint you are talking about is running vertically; up and down?
> 
> If the studs are not perfectly in line, if the stud is sticking out a bit it would make your problem worse.
> 
> ...


if you don't know what a butt joint is,how can you answer this question
he is saying his butt joint is flat,not bowed,but he says there is a cress or (sp) crease or line that is where the joint is,he also said it feels like a small bump.paper don't stick to paper .another example is a drywaller uses a rasp to shave down a butt to fit,now there are burr's (loose paper) on the butt.if they do not cut this away,the loose paper will not adhere to the rock when you mud over it.if canadian white were to cut into that area with a knife,he would find loose or burred paper.
30 years taping


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## Willy is (May 20, 2010)

2buckcanuck said:


> if you don't know what a butt joint is,how can you answer this question


Give me credit for knowing what a but joint is.
The OP posted all of 3 lines. I laid it out a little to be clear, not to ask a question. I also introduced a possibility that could be a cause that had not been previously mentioned. A butt joint on a convex stud would be tougher to get a good joint on, would it not? 



2buckcanuck said:


> he is saying his butt joint is flat,not bowed,but he says there is a cress or (sp) crease or line that is where the joint is,he also said it feels like a small bump.*paper don't stick to paper*.


The OP wrote;*
"first i mud over the tape (fiber)next coat go ether side of the joint."*
My point was that if the wall is out of plane where the joints meet anyone will have a problem whether paper or fiberglass. I'm not saying THAT'S the problem; just one possibility. It's hard to tell from the limited amount of description provided.



2buckcanuck said:


> another example is a drywaller uses a rasp to shave down a butt to fit,now there are burr's (loose paper) on the butt.if they do not cut this away,the loose paper will not adhere to the rock when you mud over it.if canadian white were to cut into that area with a knife,he would find loose or burred paper.
> 30 years taping


No argument from me. Thanks for the reply.

Willy


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## 2buckcanuck (Jul 7, 2010)

yeah ok,will ,reread your post,I paid more attention to your 1st line in the post,than the rest of it,sorry about that.
Canadianwhites fault,,,limited description:whistling


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## canadianwhite (Sep 13, 2010)

haha thanks for the imput.:laughing:


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## tomf5327 (Jan 28, 2011)

Remember a Butt Joint has no depression, like a taper joint does, so the mud will always be on top of the sheetrock. The trick is to minimize the look and feel with the taped area being the 'high spot" and the feathering extending to a resonable distance to "flatten" the area.


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