meshed tape exposed on sanding

Question

Newbie here trying to DIY somethings around the house. I am following these steps to cover/fix a ceiling hole: Put sheetrock, apply mesh tape , apply mud, sanding and painting.

When I am sanding down the Mud, I see some of the mesh tape exposed. (picture) Any idea what I should do here ? Can I just paint over it, or do I need to apply mud again and resand? Thanks in advance.

Answer 1

It's joint compound, commonly called mud, and not grout.

If you are sanding into the tape, you have not applied enough.

It's not a "one and done" product. You apply joint compound and embed tape.

You let it dry (or set, but setting compound is not the usual DIY choice.) Incidentally, USG recommends paper tape as superior to mesh unless you are using setting type joint compound (aka "hot mud.")

You lightly scrape or sand to knock off only the high points and apply more compound with a wider knife.

You let it dry

You repeat that a few times, with larger knives.

You shine the harshest light you can find at low angles and look for defects in the surface. When you reach the point that you can't find any, even after looking again from other angles, you prime and paint.

Answer 2

Welcome jav roy. Doesn't look too bad for newbie. I have been patching for years and I still have to work at it (and work at having patience) to make it look decent. The other answers and comments are excellent. I thought this would be a good chance to write some tips.

1. Multiple thin coats are better than trying to lay it on too thick.
2. Before putting on a new coat, use your knife to knock off any high points. If you do think, you shouldn't have to sand between coats.
3. Use a wide knife. My favorite is 4 inches. The wider, the smoother it will be. Keep the compound in the center of the knife so it feathers out.
4. Use a "mud pan" that has sharp metal edges for cleaning the knife off, right before you spread the compound out flat.
5. Do not put unused mud back into the container. Take out what you need (you can always get more), and throw away what you don't use.
6. I think the fiberglass tape is OK. I stick it onto the joint, then put a thin coat of mud on, pressing it through the tape. First coat is just to secure the tape.
7. Most times I can only get on three coats a day: morning, noon and night.
8. I'll apply a couple of coats over the tape, then go back later and feather the joint into the surrounding drywall. Then alternate as needed.
9. Get a rubber sanding block or better yet, a drywall sanding pad. The flat surface helps. Sand lightly with 150 grit, then switch to 220 for fine sanding.
10. When sanding, feather the edges.
11. Prime with drywall primer/sealer, then paint. I like to use a small roller for both to help the finish match the existing wall.

Answer 3

The other comments are good advice. Thin multiple coats are better than heavy coats. This creates a “hump” where your patch is. Each coat you should be using a larger spackle knife. Your final coat, sand lightly feathering out the edges. My uncle taught me a trick; close your eyes and gently rub your fingers across the spackled area. If you feel edges or dimples from air pockets, you need to recoat. I have never been disappointed using this method. When you apply the primer, it will highlight the edges and bumps, but it is very hard to sand through primer. I hope this helps. Good luck!