Bubbles

Reply

  #1  
Old 08-29-14, 05:22 PM
Temporarily Suspended
Thread Starter
Join Date: Jul 2008
Location: NY
Posts: 10,986
Bubbles

1950's house, plaster walls. There were some lumps in it. I don't know what caused them. The owner had some one grind them down & called me to patch the wall. I'm using the light weight joint compound (blue top). The first coat went on nicely but I'm getting bubbles in the second coat. What did I do wrong? Should I have used a different product? What's my next step?
 
Sponsored Links
  #2  
Old 08-30-14, 04:06 AM
Forum Topic Moderator
Join Date: Mar 2005
Location: USA
Posts: 43,804
What size are the bubbles? Large bubbles are problem, most likely caused by moisture in the the wall If they are just little pin head size bubbles it's probably were you mixed air into the mud while mixing it. They are no big deal, just sand, remove the dust and apply a thin coat of j/c.

I've always preferred to use Durabond when making repairs to plaster as it dries hard, similar to the plaster finish. Joint compound is a lot softer .... but easier to sand
 
  #3  
Old 08-30-14, 05:57 AM
Temporarily Suspended
Thread Starter
Join Date: Jul 2008
Location: NY
Posts: 10,986
They are larger than pin heads. I used an egg beater to mix the j/c before I applied it.
 
  #4  
Old 08-30-14, 06:29 AM
Forum Topic Moderator
Join Date: Mar 2005
Location: USA
Posts: 43,804
It sounds like air bubbles, no biggie, just sand and recoat with j/c.
 
  #5  
Old 08-30-14, 06:38 AM
Temporarily Suspended
Thread Starter
Join Date: Jul 2008
Location: NY
Posts: 10,986
If it happens again, should I switch to Durabond or mix plaster with the j/c?
 
  #6  
Old 08-30-14, 06:41 AM
Forum Topic Moderator
Join Date: Mar 2005
Location: USA
Posts: 43,804
The trick is not to mix the mud so aggressively. I either mix the mud by hand with my knife in the mud pan or use a slow speed drill and paddle in a bucket.
 
  #7  
Old 08-30-14, 06:52 AM
Temporarily Suspended
Thread Starter
Join Date: Jul 2008
Location: NY
Posts: 10,986
I mixed it with a variable speed cordless drill that needed to be recharged. So the speed was minimal. I'll see what happens later.
 
  #8  
Old 08-30-14, 09:25 AM
Forum Topic Moderator
Join Date: Mar 2005
Location: USA
Posts: 43,804
It might be the technique you are using to mix the mud. You want to keep the paddle in the mud and limit how often you lift it out and plunge it back in [bringing air with it]
 
  #9  
Old 08-30-14, 11:57 AM
Temporarily Suspended
Thread Starter
Join Date: Jul 2008
Location: NY
Posts: 10,986
I went back there today. The bubbles seemed to have taken care of themselves for the most part. I sanded & touched up a few sections. Someone else is going to paint so I told the home owner to have him put a coat of primer on it & to tell me if any more touch-ups are needed before he paints.

Thanks for the advice on how to mix the mud. I pretty much did exactly what you said but I'll be more conscious of it, in the future.
 
Reply

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread
Display Modes