Drywall - final joint compound coat

Question

While remodeling an older house (where nothing is quite straight) we used fiber glass mesh joint tape and 3 coats of joint compound. The first coat was applied with a 4 inch knife, the second with an 8 inch and ending the third on a 12 inch knife. I can still see the texture from the mesh tape I used on some of the joints.

I hoped that a coat of primer would level it off, but after using Kilz 2 primer I can still see the tape in some spots. :(

Sanding through the primer now proves difficult (doesn't work) with a medium grit sanding block.

Should I add another coat? I could never quite get the joint compound to adhere over the mesh tape. I've always been taught to go as thin as I can on the joint compound to reduce the sanding part. Did I go too thin?

I'm hoping a second coat of primer and 2 coats of the final latex paint hides it, but I know this isn't the right answer. How can I fix this?

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following what doresoom and shirlock said; i just applied a coat with the 12 inch knife practically against the wall (accidentally touching the wall with the handle once or twice) - more or less dragging the compound across the surface

this produced the result explained - about 1/32nd ? thickness of mud, covering the tape that i'll need to feather round the edges

i miss spoke earlier - i was using a sponge sanding block (not strait paper sand paper)

now that the primer has dried (did it saturday) its not as bad as i thought it was, but this is the right way to do it (not covering it with paint)

just as a side, we've used sherwin williams paint throughout the house and although its great paint (IMO) the plaster and lath walls that remain, even those repairs show through - and if those do, than this new work will... may as well do finish it right...

thanks for the help guys - i'll check this coat tomorrow and give a last one with the soap and water if it needs it.

Answer 1

I know this isn't the answer you want to hear, but I don't think priming and painting will hide the tape.

Before you apply any more primer, I'd add another thicker coat of mud. Slather on the mud thick first - it doesn't have to be smooth. Then smooth it out by angling your 12" knife so it's almost parallel with the drywall as you drag it along the surface. You'll have to press fairly firmly in order to avoid air gaps appearing in the thick coat you're smoothing out.

You may have to get a feel for it. If you push too hard and can see the tape again, redo that section until you get it just right.

Wait for the thicker coat to dry, then sand the edges as smooth as you can get them. Very carefully/lightly sand over area covering the tape if you didn't get it quite smooth. You may need to do a second coat along both sides of the thicker coat to make it join the drywall surface smoothly.

Answer 2

As the others have said, paint will not help your situation. You will need to apply another coat of mud. The final coat can be applied using a 12 inch flat knife, but I personally like a 14 or 16 inch bow trowel. The idea is to have a thicker coat of mud over the tape and bevel or feather the edges out wide so you will not notice the small difference in thickness. With a 12 inch knife, your joint should be about 16 to 18 inches wide. Push harder on the outside of the knife than on the inside/center of the joint. This will leave more mud in the center and feather the edges better. Do this on each side of the joint.

Here is another tip for you. For your last or final touch-up coat, mix a little extra water and some Ivory dish soap into your mud. It will flow very easily, far less tiny air bubbles, and will sand out easy with little pressure. Never use sandpaper, use a 150 or 220 sanding sponge. Don't go crazy and strip it too much or you will expose the tape again. Smooth the center gently and feather out the edges more agressively. Good luck

Answer 3

Mistake #1. Never use mesh tape with pre mixed joint compound. Mesh tape is for setting type (powder mix) compound. Also never use paper tape with setting type compound.

Mistake #2. Bubble problem. Always make sure that you have a BLEED OUT when you set the paper tape. Bleed out = when you're pushing the tape into the compound make sure you see excess compound squeezing out on sides of the 4" knife. If you don't, then you don't have enough compound on the wall. Pull the tape and do it again.