Repaired Drywall Issues - DIY Chatroom

bsmith6356 · 11-03-2009, 08:26 PM

Hi there-
I have two problems that I always run into when repairing drywall.
Yesterday I cut out a 16" x 12" piece to feed some electrical wiring behind. I kept the same piece of drywall that I cut out, and made sure I cut down the center of the studs. Placed in a stud horizontal for the piece to screw into at the top. Screwed the piece in.
Here's where I run into the problem:
I put a light coat of mud across the cut area (and in the gap between the new piece and wall) for the tape to stick to, and then tape it. Take my knife and push out the excess, and then apply a first coat of mud. EVERY single time I do this, I get a bulged OUT area where the gap was from the mud underneath. When I sand, I don't want to go down to the tape, so I still end up with the bulge in the gap area. Second coat I try to taper out the bulge...but now I've got a wider, tapered out, slight bulge.

Most people may not notice it, but it bugs me. What am I doing wrong that creates the original problem?

And second...
When you paint an area that has had a drywall repair done, I always get a different "look." There's the smooth, newly sanded mud area, and then the regular wall that is more rough from previous paint jobs. And if it's in an area near a light, you almost get a "gleam" or "glossier" look to the painted area over the mud (yes, using the same satin paint). What do I do?

Thanks, and sorry for being so long-winded!
Brent

fltdek · 11-03-2009, 09:41 PM

I'm not a "Master Mud Man", but I have come across this in work I've done. Maybe the width of your gaps? For me, after applying the tape, during the drying stage, if I find the buldges, I will take a utility knife and "deflate" the buldge. Then apply another thin coat of mud. Usually solves that issue for me. I didnt see you mention anything about priming berfore painting - did you forget to mention or leave that step out?

pyper · 11-03-2009, 10:06 PM

Do you use the same type of roller to paint? I always prime and paint the repairs with the same type of roller and they seem to bend in well.

Also, when the roller has very little paint left, I feather the repair area into the adjacent areas, so if it's not an exact match it will blend.

ArmchairDIY · 11-03-2009, 10:37 PM

I think you may be putting the second coat of mud on too soon. The moisture from the second coat is drawn into the first creating a blister in the tape. Or as fltdek said it could be the gap is too big.

Are you priming before you paint with a good quality primer?

bsmith6356 · 11-03-2009, 10:59 PM

No, I'm not priming...probably what the problem is!
And as far as the gap size, we're only talking about 1/4" max. I'll try the "slit and deflate" (happened when my wife found my last blow-up doll) method next time. Thanks guys.

Maintenance 6 · 11-04-2009, 08:21 AM

Try mudding in the gap and letting it dry before you apply the tape. Also make sure your roller is well loaded with paint. Don't try to dry roll it.

bjbatlanta · 11-04-2009, 05:59 PM

Allow the tape to dry thoroughly before applying your next coat of mud. And make sure there is mud behind ALL of the tape. Any tape not properly adhered with mud will "blister". You shouldn't need to pre-fill. If you're in a hurry to get done (likely why you're mudding over wet tape??) use setting compound, say 45 minute so you can re-coat in a shorter time span. You can use the 45 min. for the first coat over the tape too and skim with regular ready mix. You can use 20 min. if you're pretty good with mud, but 45 or even 90 gives you more working time.......
And it's ok to sand down TO the tape as long as you don't "burr/fuzz up" the surface of the tape. Tape is a "paintable" surface.

hyunelan2 · 11-04-2009, 06:10 PM

I always had a hard time getting tape perfect, I recently switched to using the "mesh" type and have had much better patches than I did with paper.

bjbatlanta · 11-04-2009, 06:18 PM

The only time I use mesh is on smaller repairs where I need to do multiple coats in a short period of time to get done in one trip. ANY time you use mesh, setting type compound should be used AT LEAST for the first coat. It does give a bit "flatter" surface in the long run due to not having a layer of mud under the tape as you would have with paper tape. Thus for the DIY'er you don't have to make the overall coverage of the patch as large to blend without a noticeable "hump".......

GBR in WA · 11-04-2009, 07:37 PM

What do you think, BJ? http://www.plaster-wall-ceiling-solu...wall-tape.html
Be safe, Gary

bjbatlanta · 11-04-2009, 11:55 PM

If used with setting type compound, the mesh works fine in my experience. It got a bad rap when it first came out when finishers thought it was the answer to speeding up the finishing process while saving money. A $7.00 an hour laborer could string tape and someone halfway adept at "smearing" mud could follow with a first coat. Usually regular ready mix was used for convenience sake. Movement in the walls would cause the joints to crack, quite often seen over door/window headers where more movement was prevalent. (And I might add this was usually commercial, not residential work.) Most often, finishers went back to, and still rely on, paper tape for new construction. Some figured out that setting compound, especially regular Durabond, more so than the Easy-sand type, solved the problem. Mesh tape never really regained acceptance in the trade though. As stated before, when used with the proper joint compound, it works fine for drywall and/or plaster.....

bsmith6356 · 11-05-2009, 01:58 AM

Thanks for all of your input, guys, I really appreciate it. Using primer solved the "glossy-look" issue I was referring to.
As far as the mudding advice, I'll have to try the advice on the next project. I was already on my second coat of mud when I wrote this. I saved out the forum posts so that I can reference it next time!
Brent