I've Got A Plaster Patching Problem

Relic

i'm doing some drywalling, and need to run it into a pretty uneven plaster and lathe wall. any suggestions on getting a nice finish? can i just use a whole ****load of mud? maybe i should just suggest that the customer think about wallpaper.

72chevy4x4

I'm not a plaster man-you should post in the drywall forum for a better response. me thinks a long straight edge is in order for the rough coat plaster. on the other had if you're putting wallboard over top, then put 1x3 strapping on the wall and shim it out-making sure you screw overtop the strapping! This doesn't take into account w/ incidentals such as outlets being too far in, window jams needing extending or whatever else may come your way.

BUTCHERMAN

Yes I Do These All The Time.if You Are Trying To Tie In Dry Wall And Plaster The Best Thing To Do Is Use 3' Wide Fiberglass Mesh To Conect The 2 Areas.then Mix Ez Sand 45 A Little Loose Like Taping Mud For Banjo Or Bazzoka.then On Your Hawk Thicken It With Handfulls Of Diamond Plaster.this Is For Strenght And Texture.fill In The Heavy Fill Areas.when That Sets Up Take A Tooth Trowel And Float The Area.then Lightly Take A 12' Taping Knife To Even Out The Grooves.heres The Trick.as It Drys Because Of The Diamond You Can Smooth It When It Drys For About 15 Minutes.so Let It Dry And Take Your 12'knife And Flaten It Out.then I Suggest A Skim Of Ez Sand And A Skim Of Midweight.pulling In 2 Different Directions.meanning Ez Sand Pull North And South. Midweight Pull East And West.but Pull The Midweight With The Light.this Tecniche Takes Patience But It Works.good Luck

Muddauber

Butcherman,
I've never tried mixing diamond with ez sand.How does it affect setting time?

BUTCHERMAN

It accelerates it.I can mix loose 20. Put put some on my hawk add about 2 handfuls of diamond (on the hawk) and coat the patch three times with the same mix of 20. But the great thing is when the ez sand/diamond mix sets up you can smooth it with knife to get out lap lines. Then you can top it with lightweight on and off. Do it right theres no need to sand. It's also fun to experiment other uses for this it's good to know.

Heritage

First thing first make sure you're getting the right thickness in your drywall, not all lathe and plaster thicknesses are the same. Use variations of 1/4,1/2 and 5/8...5/8 usually does it but don't be mistaken...you don't want to be left with a 1/4 shallow drywall that you're going to have to mud over...entirely.

Next, make sure the L&P is solid.

You've cut the L&P which means you compromised it's integrity, general rule is if you can pull it off with medium pressure with the hand (pulling) then it's gotta come off so keep pulling it off until you can't take any more off without the use of a pry, hammer, etc.

Obviously try to cut straight joints...no jagged corners

Then go with what Butch said...I haven't done the 3' mesh thing yet though...sounds like a good idea.

I do this far more often than I ever wish to, but it always comes out seamless. And yes you will use a buttload of mud

In the end try to stay away from having to do this but sometimes the situation calls for it...I ALWAYS prefer to tear the whole wall down and go fresh.

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BUTCHERMAN

the 3' mesh we use to tie things together.you cut the pieces to sizes you need.sometimes you have to leave gaps bettween the new rock and old plaster of 6"'s or more because of thickness difference.the wide mesh mkes it easier to tie together.also if you have a wall that looks like a spider web you can open the cracks, mud the wall and apply screen over entire wall.then float with trowel.there are so many things you can do with the big screen.i won't get in to it but you will find them on your own.

neolitic

You're talking regular screen door fabric here?

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rbsremodeling

Neo not sure if you were kidding or not but its a mesh drywall tape that you use for patches

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BUTCHERMAN

acutaly it's mesh stucco guys use to wrap a house on the outside when they stucco

neolitic

Wasn't kidding.
Never saw fiberglass mesh 3'
except screen fabric.
Not that much stucco on residential
in these parts, and I don't spend that
much time hangin' at the drywall supply.
Those guys it's mostly, I call...they bring.
Thanks for learnin' the old guy!

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BUTCHERMAN

Check with your supply house. They should have it or can get it. I should also mention it's not self adhesive so you need to set it with mud. I prefer dura bond or ez sand. You can get self adhesive but i find it to be very weak and it's too fine

Sir Mixalot

Usually the plaster varies in thickness. What I do is get a measurement of the thickness' @ the point where i will be intersecting drywall to plaster. Then plan on shimming it out to the plasters thinest point @ that intersection. Say you need 3/4". Use a 1/4" and 1/2" sheets of drwall. You could just put strips of 1/4" drywall @ the studs then attach a full size peice of 1/2" drywall. Then after all of the mud work, if the existing plaster wall has a sanded finish. You can mix up some joint compound to an Orange peel
consistency and add some sand and a little paint then spray this mix on the new drywall (w/ a hopper) feathering out a little on the old plaster for blending. Good Luck!