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Vertical seams giving me issues....Need advice

636 Views 20 Replies 5 Participants Last post by  endo_alley
This particular problem has been plaguing me all winter, and honestly anywhere I'm finishing vertically laid drywall.

After my initial tape coat. I'm applying first coat of mud with 8 inch knife. Then the second coat with a ten. And then either finishing third coat with a 12 or a 10 again. My finished product has a dip in it Uniformly from floor to ceiling. I have attempted to go back over with an 8 inch knife and it doesn't seem to remedy this. This doesnt happen on my horizontal seams. I hope someone has some advice on this.

Thank you
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This particular problem has been plaguing me all winter, and honestly anywhere I'm finishing vertically laid drywall.

After my initial tape coat. I'm applying first coat of mud with 8 inch knife. Then the second coat with a ten. And then either finishing third coat with a 12 or a 10 again. My finished product has a dip in it Uniformly from floor to ceiling. I have attempted to go back over with an 8 inch knife and it doesn't seem to remedy this. This doesnt happen on my horizontal seams. I hope someone has some advice on this.

Thank you
Had the problem b4 on commercial stuff, real faint dip, told it was acceptable馃檮.
Yeah I pretty much was told the same thing but it bothers me

What do you think it is the fact that it's a vertical seam the way that you're putting pressure on I can't figure it out
Yeah I pretty much was told the same thing but it bothers me

What do you think it is the fact that it's a vertical seam the way that you're putting pressure on I can't figure it out
Steel of wood studs?
I had same problem on a vertical hang on wood. What i came up with was the slight bow/crown made it much easier to wipe out more mud. I boxed it with a 15" 2x.
I had same problem on a vertical hang on wood. What i came up with was the slight bow/crown made it much easier to wipe out more mud. I boxed it with a 15" 2x.
Could you please explain what you mean when you say you boxed it? Obv the "15 2x is a 15in knife done twice right? The only reason I even question that part is because I don't think I've ever seen a 15in knife. And I don't know what boxed it mean either.

I will include some pictures. I have roughly 25 vertical seams on this job. I tried all sorts of different ways to fix this. I'm only 1 coat over tape right now. I would really like to get this remedied. Again , ty very Much for your advice.
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Could you please explain what you mean when you say you boxed it? Obv the "15 2x is a 15in knife done twice right? The only reason I even question that part is because I don't think I've ever seen a 15in knife. And I don't know what boxed it mean either.

I will include some pictures. I have roughly 25 vertical seams on this job. I tried all sorts of different ways to fix this. I'm only 1 coat over tape right now. I would really like to get this remedied. Again , ty very Much for your advice. View attachment 42092
A 15" flat box.
A 15" flat box.
Ahh, ok, yeah I have absolutely no experience with any auto tools.

I tried doing two swipes with a 6 in knife. Going approximately 2 inches on the right side of tape , and then another pass 2 inches over the the left side of the tape. And then wiping off with a 10in knife. This seemed like it helped but it doesn't seem consistent.
Ahh, ok, yeah I have absolutely no experience with any auto tools.

I tried doing two swipes with a 6 in knife. Going approximately 2 inches on the right side of tape , and then another pass 2 inches over the the left side of the tape. And then wiping off with a 10in knife. This seemed like it helped but it doesn't seem consistent.
You need 10, 12 and 14" knifes, find a small drywall co, or a semi retired drywaller they can knock it out fast .
A 15" flat box.
Ahh, ok, yeah I have absolutely no experience with any auto tools.

I tried using a 6in knife ,
You need 10, 12 and 14" knifes, find a small drywall co, or a semi retired drywaller they can knock it out fast .
Oh I have all the knives I need I'm just saying that I've tried a number of different things ok on my first coat after tape up to and including trying two passes with a 6in trying to fill in the dip.
Ahh, ok, yeah I have absolutely no experience with any auto tools.

I tried using a 6in knife ,

Oh I have all the knives I need I'm just saying that I've tried a number of different things ok on my first coat after tape up to and including trying two passes with a 6in trying to fill in the dip.
Put a 12 on seam and see if it rocks like a butt joint if it does finish it in same matter as a butt joint.
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bingo! what he said. vertical hang blows. lol
After tape coat. Run 10 inch knife on each side. After that dries then run 10 inch down middle. After that dries run 10 inch down each side of that run.

That don't do it, using to much pressure
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So the wall got painted, I got a text on sat morning that all the seams are visible.

I tried to fill em in . I'm not sure how successful I was.

I was wondering if a skim blade would help here. I have some new verticals to do and I'm definitely going to try the 10in knife practice that was suggested. I'm thinking my boss may just go get a 15" flat box. I've never used auto tool , but only because I can't afford them. Lol

I really appreciate everyones time, and help. Thank you
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a box is just to get mud on wall fast. they arent magic or going to be able to put on the mud the way you need. you will just have to knife them and see what each one needs. shine the light rite down the wall setting up against it. that will tell the whole story and nothin but he truth. lol

say again vertical hanging(n) blows.
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View attachment 42095

So the wall got painted, I got a text on sat morning that all the seams are visible.

I tried to fill em in . I'm not sure how successful I was.

I was wondering if a skim blade would help here. I have some new verticals to do and I'm definitely going to try the 10in knife practice that was suggested. I'm thinking my boss may just go get a 15" flat box. I've never used auto tool , but only because I can't afford them. Lol

I really appreciate everyones time, and help. Thank you
You'll regret the 15 inch flat box. If for nothing else just the weight of it.
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Looks like a combination of too much knife pressure and too much sanding, mixed with not wide enough feather. My standard rule on butt joints and vertical (B.S.) hangs is 30 inch wide. Like said above, vertical hang sucks
At this point馃檮, id grab a paint roller 1.25" and roll each joint and skim with 32" blade. That should put this matter to rest馃樂
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