How to find drywall joint when it's covered in mud?

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farmerjohn1324

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I'm mudding and taping a drywall ceiling.

After mud is applied, I can generally estimate where the joint is, but I've found that I've been off on several occasions when trying to put the tape right in the middle.
 
Speed is a component as is the weight of the first application, IE. the thinner the coat, the easier to follow the seam.

Using self adhesive fiber tape eliminates that concern, because it's applied 1st.

Also if you have a large project, adding some food coloring tells you where you are as the coats proceed.
 
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Speed is a component as is the weight of the first application, IE. the thinner the coat, the easier to follow the seam.

Using self adhesive fiber tape eliminates that concern, because it's applied 1st.

Also if you have a large project, adding some food coloring tells you where you are as the coats proceed.

I'll get self-adhesive tape next time. It may even make up for the price I would save on not needing that first coat of joint compound.
 
I'll get self-adhesive tape next time. It may even make up for the price I would save on not needing that first coat of joint compound.

The first coat should fill any gap and be scraped off. I have never done that first coat but a few times I should have.:)
 
I'll get self-adhesive tape next time. It may even make up for the price I would save on not needing that first coat of joint compound.

Taping is a 3 coat process, the first fills the tape and is tooled with a 6" knife, the second fills the void between the sheets and is tooled with and 8" knife and the third is the topping product and is tooled from both sides with a 12" knife.
 
Taping is a 3 coat process, the first fills the tape and is tooled with a 6" knife, the second fills the void between the sheets and is tooled with and 8" knife and the third is the topping product and is tooled from both sides with a 12" knife.

What could between sheets are you talking about?

Is the 3rd coat joint compound?
 
What could between sheets are you talking about?

Is the 3rd coat joint compound?

On the tapered edges of the drywall, you're trying to fill in the taper to make it flat. With butt joints, you don't have the indentation so you will have a slight hump at the joint that you need to feather out to make it less noticeable. Butt joints tend to be wider than the edge joints.
 
The putty knife you are using for the first coat may be too wide. A four inch blade will fill the seam and the depressions at the edge of the sheets. As soon as you have applied the mud press the tape into place. it's really hard to miss the seam if you are putting three inch tape in a four inch trough.
But you may be better off with this: https://www.homedepot.com/p/Saint-G...wall-Joint-Tape-FDW8660-U-FDW8660-U/100401003 which eliminates the need for an embedding coat.
 
Here is a decent video from Fine Homebuilding on how to do it.

[ame]https://www.youtube.com/watch?v=j3ME-c96874&ab_channel=finehomebuilding[/ame]
 
What could between sheets are you talking about?

Is the 3rd coat joint compound?

The 3rd coat is Topping, it's a product as well as a function, and while it dries hard, it's composition is finer leaving a paintable surface, after easy sanding.
 
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