Monday, November 10, 2008

Getting Plastered

Prompted by Jason's comment left on the previous post I thought I'd share the method used in fixing all the cracks in the walls.

All of the pictures I'm using are from the How 2 Plaster web site - THANKS GUYS!!

Okay - with that said - buckle up and get ready to get plastered.

This first pic is a schematic of the process - fairly straight forward.







However, whenever possible I would underscore the plaster in order to create a better key.

He is what a typical spot looks like - but then again I'm preaching to the choir aren't I?!?!






To be honest, there were maybe one or two spots like this on the kitchen walls. Most of the cracks were just the typical type ones.

This shows the hardest, and messiest part, at least to me.

You need to scrape the old plaster back and get it down to the lath. It is also important at this time to make sure all the loose pieces are gone. Think about the crack, and any loose plaster, as a cancer. It needs to be cut back till you find good, strong plaster. Usually though, this cancer step applies to larger areas with loose plaster. However, when I scrapped the cracks I did find loose pieces I did not know where there to begin with.

Note: on the right tail-end of the crack you can see the typical type ones we had.

When finished, this is how it should look. Here you can see the lath, but notice the 'V' that has been formed.

Not sure why but every book and site says to make this 'V'. I guess it helps provide a better surface for adhesion.

The next step is a two parter.

First, use an old paint brush and get all the dust and small pieces out.



THIS STEP IS VERY IMPORTANT!!

Second, you are suppose to wet the old plaster to insure a good bond. I go one step further and use a plaster/concrete bonding adhesive.


This is what it should look like. If it is - then your ready to start plastering.






Fill the crack with your patching mix. Don't worry too much how it looks right now, just don't get too wild.



Now, with the crack filled, go over it again to scrape off the excess. You will need to hold the scraper hard against the plaster to make sure you get a nice, even, scrape.

This is about how it should look once you are done with the first scrapping. Again, don't worry how it looks. In fact, while it dries there will be some cracking and shrinking depending on the size of the repair.

After your first patch has dried it is time for your second patch.

At this point is where some controversy pops up. Some people say you need to put mesh on top of the patch before your second coat. Some say you only need to do this if the crack is more than 1/4" or more than 1/2" wide. There will also be those who tell you NOT to use the mesh (due to bulk) but use the standard mudding tape. It is really up to you. I have tried all the mesh, the paper and nothing. It just depends on the size and your preference. On small ones I usually go with the mudding tape and the larger ones I use the mesh. Mesh, nor paper, were used in this patch.

Also, this is the time to try and make your patch as smooth as you can when you scrape the excess off. Even though it is not your final coat, this one will help your final coat look as good as it can.

Here is what it should look like when you are done and the second coat has dried.

Your next step will be your finish/top coat. after this, especially if I have a lot of cracks to fill, or as was the case with our kitchen walls, I will finish it all out with a skim coat. This will give it a nicer, smoother, flatter look.

One thing I will point out - be sure to prime your finished plaster with the correct primer!! You can not just use your typical interior house primer. You MUST you a PVA drywall primer.

Well, till next time...

Cheers!
Larry

2 comments:

Sandy said...

That takes a whole lot of patience!

Larry said...

Yes...yes it does. That's one of the reasons it has taken so long!