Plastering outside corners. Any tips?

Philament · Jan 29, 2016

I don't know if this is the right section, but plaster seems to be more like a masonry application than drywall.

I've been trying my hand at veneer plaster in the shop (USG Diamond basecoat and finish gypsum plaster) making a few mockups. I'm using CornerAid for the outside corners, but I'm have a real hard time getting straight outside corners and wondering if you have any tricks/techniques to share that might make it a bit easier.

Here's the mock up (I put a plaster bonding agent on before base coat)

I just did a base coat (brown coat ?), but I'm not happy with how it came out, so I'm thinking of maybe doing another basecoat to get the lines straightened out.

When I've done parging in the past, I've sometimes used the wet board technique against the corner, then run the trowel up to it, but it doesn't seem to work very well with the plaster.

I picked up an outside corner trowel, but it seemed to make the problem worse.

fjn · Jan 29, 2016

Just work to the corner bead,if the bead is straight the corner should be straight. Especially in veneer plaster,each coat (base and finish) should be no thicker than 1/8 " per coat.

Philament · Jan 29, 2016

fjn said:
Just work to the corner bead,if the bead is straight the corner should be straight. Especially in veneer plaster,each coat (base and finish) should be no thicker than 1/8 " per coat.

Any suggestions on the type of corner bead for plaster? I was worried that using metal drywall corner bead would give enough mechanical bonding and they yards here can't seem to get the Sheetrock 900 profile, so I went with a stucco corner bead with plastic nosing, but it's wiggly as a noodle.

Philament · Jan 29, 2016

fjn said:
Just work to the corner bead,if the bead is straight the corner should be straight. Especially in veneer plaster,each coat (base and finish) should be no thicker than 1/8 " per coat.

Maybe I put it on too thick. I was doing 1/8"-1/16 then doubling back while still wet with 1/8" - 1/16". The application guide was a little fuzzy on that, if it was supposed to be 1/8" total after doubling back, or no more than an 1/8" per application.

fjn · Jan 29, 2016

Yeah,you definitely have the incorrect corner bead.You need to get with a supply house that can access the right stuff for you. That system you are using is absolutely top notch in my book. Do not get discouraged,get the proper material and you will be fine. Also,do not over trowel either coats,especially the base. I will search the great youtube videos and post them for you. The guy hosting is a teal straight forward and good mechanic.

fjn · Jan 29, 2016

Here is one for you.

stuart45 · Jan 30, 2016

Paul Harper has also done some useful videos.
I've never got as good a finish as a real pro plasterer.

Philament · Jan 30, 2016

fjn said:
Here is one for you.

Thanks FJN. It was actual another video of Kirk's that lead me to the CornerAid when I couldn't find proper veneer plaster corner bead.
I think what I actually got was CornerAid for a arched corner instead of the straight ones. For some reason I just figured you had to float the corners with some special technique

These were the vids where he was using corneraid for veneer plaster, but it never really did show how he finished out the outside corners. He used Structolite as a base instead of Diamond base, but I don't think that makes any difference.

superseal · Jan 30, 2016

Mini veneer bead works well for veneer plaster work. You can additionally use #1 expanded corners if your doing conventional

http://www.phillipsmfg.com/mini-veneer-bead/

http://www.phillipsmfg.com/stucco-and-plaster-casing-beads/

fjn · Jan 30, 2016

I can see why Kirk used structolite as a base for the fireplace,you need a thicker base to cover the tooled joints of the brick. If I will be going over block work,I never strike the joints.The veneer base works fine then.

fjn · Jan 30, 2016

By the way,Philament you may want to pick up a copy of this book,it really is the 'Bible' of the industry.

http://www.amazon.com/Gypsum-Constr...118749847/ref=sr_1_1?ie=UTF8&qid=1454195258&sr=8-1&keywords=plastering+handbook

Tscarborough · Jan 31, 2016

Corner-aid, and do the corners first and work to them, just like you do with masonry. Wind-lock makes corner tools, inside and out that work great. Like this:

http://www.wind-lock.com/en-us/prod...en-us/product/0124/exterior/hand-tools/t-45l15/2in-lh-wood-corner-edger-45.aspx

Philament · Feb 1, 2016

fjn said:
By the way,Philament you may want to pick up a copy of this book,it really is the 'Bible' of the industry.
http://www.amazon.com/Gypsum-Constr...118749847/ref=sr_1_1?ie=UTF8&qid=1454195258&sr=8-1&keywords=plastering+handbook

Thanks fjn. After playing with the the finish plaster this weekend, I'm starting to get a little more confidence. It was a lot easier to work with than the base material. What I'm finding though is that this involves just a lot of practice and just trying different trowels/tools/techniques. It's quite different than any material I've worked with before. Will a book help much to get a better handle on this stuff?
I can see now why this is art.

Philament · Feb 1, 2016

Tscarborough said:
Corner-aid, and do the corners first and work to them, just like you do with masonry. Wind-lock makes corner tools, inside and out that work great. Like this:

http://www.wind-lock.com/en-us/prod...en-us/product/0124/exterior/hand-tools/t-45l15/2in-lh-wood-corner-edger-45.aspx

Thanks Tscar,
That's the outside corner trowel i bought and it seems to be working better with the finish plaster. I dabble in masonry, but I am no means a mason, so these outside corners and techniques are new to me. Thanks for taking the time to try to point me in the right direction.

fjn · Feb 2, 2016

Philament said:
Thanks fjn. After playing with the the finish plaster this weekend, I'm starting to get a little more confidence. It was a lot easier to work with than the base material. What I'm finding though is that this involves just a lot of practice and just trying different trowels/tools/techniques. It's quite different than any material I've worked with before. Will a book help much to get a better handle on this stuff?
I can see now why this is art.

While a book is not as good as a video or having a hands on teacher to guide you, there are benefits to a book. One thing,they are great resources to show you what products are available along with specs. explaining how said products need to be installed.

When you think of it,the book only costs about the price of four bags of material.

Also,just a bit of info./ nuances of veneer plaster; The substrate / blue board needs to be plastered somewhat soon after installation. Sun will fade the paper and somehow effect the bond. Also,my go to bonding agent (if needed) is Larson's Plaster Weld,the blue can.:thumbsup:

fjn · Feb 2, 2016

I'll be darned,I just googled Larsen P.W. and they switched can colors from the blue for boys,to the pink for girls.:laughing:

Philament · Feb 2, 2016

fjn said:
While a book is not as good as a video or having a hands on teacher to guide you, there are benefits to a book. One thing,they are great resources to show you what products are available along with specs. explaining how said products need to be installed.

When you think of it,the book only costs about the price of four bags of material.

Also,just a bit of info./ nuances of veneer plaster; The substrate / blue board needs to be plastered somewhat soon after installation. Sun will fade the paper and somehow effect the bond. Also,my go to bonding agent (if needed) is Larson's Plaster Weld,the blue can.:thumbsup:

Fair.
Can you explain what the difference between Larson's Plaster Weld and Larson's Weldcrete is? All of the masonry houses here carry weldcrete, but nobody here has ever even heard of plasterweld or wont order it for me. The only plaster specific bonding agent I could get locally was BASF Master Protect P110 (formerly Thorobond).
http://www.master-builders-solutions.basf.us/en-us/products/masterprotect/1883

fjn · Feb 2, 2016

Plaster weld is for interiors only.

Plastering outside corners. Any tips?

Philament

fjn

Philament

Philament

fjn

fjn

stuart45

Philament

superseal

Attachments

fjn

fjn

Tscarborough

Philament

Philament

fjn

fjn

Philament

fjn

Top Contributors this Month

Recommended Communities