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Discussion Starter · #1 ·
i have never repaired a plaster wall or ceiling personally. I remember my boss installed sheet rock on a remodel(demo) right next to plaster and then skim coated a few times. However, I didnt get to see the finished product. I dont know how the wall looked once painted.

Is that improper? I have never worked with plaster, so I could use some help on what my options are.

1)Chunk missing from plaster. Can i skim it with joint compond?
2)Patch needed in plaster. Can I use sheetrock and skim.
3)How will primer and paint blend transition from plaster to joint compound?

thanks
 

· PinheadsUnite
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i have never repaired a plaster wall or ceiling personally. I remember my boss installed sheet rock on a remodel(demo) right next to plaster and then skim coated a few times. However, I didnt get to see the finished product. I dont know how the wall looked once painted.

Is that improper? I have never worked with plaster, so I could use some help on what my options are.

1)Chunk missing from plaster. Can i skim it with joint compond?
2)Patch needed in plaster. Can I use sheetrock and skim.
3)How will primer and paint blend transition from plaster to joint compound?

thanks
1) Yes, but you need multiple coats to build and feather.

2) Yes, but I prefer patching plaster. And if it's down to the lath and large enough, I will use Structolite and a veneer plaster plaster.

3) sometimes the transition from JC to plaster will flash because of the porosity of JC.

A great ability is to learn how to patch and blend plaster properly. Something I always wanted to learn, but only recently have somewhat "mastered". Veneer plaster does not want to adhere to old base coat plaster - there is no tooth. There are bonding agents that allow new veneer plaster to adhere correctly. I learned that the hard way many years ago patching the skim coat in a bathroom.

If you ever have an opportunity to learn plaster repairs from a master plasterer, jump at the chance.
 

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I too use structolite for scratch coat then 2 layers of setting JC to blend with old plaster level. Make sure you wet the lathe first (if its wood) and check that the surrounding plaster is secure. For the last 2 coats (brown & finish) you can use lightweight setting joint compound (I use 20 or 45 min) and I also use the bonding adhesive (Quickcrete concrete bonding adhesive for concrete, mortar and plaster). It is considered an acceptable patch by most plaster purist but some would still mix the lime putty and sand.
The other way would be to get a bag of lime, Type s or n, slake in water for about 24 hrs then mix with sand. Wet between each layer and compress the last. Prime with a primer for high PH (8-10)
 

· PinheadsUnite
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redi patch is amazing if its the stuff im thinking of..black can with orange writing by MH or something..I resurfaced my parents spider cracked garage door with that stuff like 10 years ago and it still looks good. I think I will try that.
MH Ready Patch is made by Zinsser. The big Z's parent co, RPM, bought MH (Mantrose-Haeuser ) less than ten years ago.

I agree, it WAS a very good product. Who knows what Zinsser has done with it.

Other RPM companies: Bondo, DAP, Modern Masters, Parks, Rust-Oleum, Testors, Watco , Wolman Wood Care.

-Bill
 

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Durabond 90, 45, and 20 sand differently from each other (all brown bag - setting type of JC).

Don't take this to the bank, but I think the 90 is the hardest to sand and the 20 is the easiest - but I could have that bass ackward
 

· The Lurker
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Durabond 90, 45, and 20 sand differently from each other (all brown bag - setting type of JC).

Don't take this to the bank, but I think the 90 is the hardest to sand and the 20 is the easiest - but I could have that bass ackward
Brown bag is hard to sand no matter what number.. White bag to me sands fine either 5, 20 , or 45 I don't use much 90...
 

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mak,

I can't find any "white bag" durabond on the USG website. Do you have, or can you find a link to a product description ?
 

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got it !

no it's not "durabond", but it is still a USG product. It's one of the lightweight jc's under the "Sheetrock" brand.

my jury is still out on the lightweight jc's. I've sparingly used the lightweight ready-mix (drying vs setting) with no ill effects, but I'm just old school enough to be wary of something named "lightweight".

And yes, all of the lightweights are very easy to sand.

I'd love to see pro's and con's of the lightweights vs the regulars.
 

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This is what I do:

If the work is down to lath board: Clean the area up. Remove the loose plaster, make sure the lath is nailed down properly. Bevel cut solid edges. Spray wooden lathe, mix up plaster of paris with a little retarder to increase wet edge (working time). Skim with broad knife or trowel. Feather to same height as adjacent area. Let the plaster cure somewhat. Hit that hot patch with a primer like BIN-Stain Killer-Kilz--oil base preferable. Skim with jc of your choice. Feather sand. Prime one more time with finish material you are going to use. Good to go.

You really have to do this process lots to get it perfected, but this little explantion should get you started anyway.

JTP
 

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Also, do not do the amateurish mistake of doing your repair work, and sealing up all the moisture behind the plaster. Take a hint from this plaster water damage page and make sure it is all dry behind there before you do the repair job.
Unless of course you recognise that practise makes perfect, and you want to do it again in a few months time.:blink:
 
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