Repairing Plaster Crown Moulding Questions

[lovesickest]

I am finally doing the plaster repairs on my long neglected livingroom (don't even ask). The wallpaper was stripped about 100 years ago(exaggerating) and most of the walls are in great shape give or take some hairline cracks. There is plaster crown moulding that has a few cracks on it. It feels more fragile/brittle than the wall plaster. The cracks do not appear to be the result of water infiltration.

I have no experience with this except for some basic patching. My plan is as follows:

- load patching compound into the sort of bag that is used for cake icing and fill the deep cracks like this.
- do a couple of applications, waiting for it to completely dry between applications
- do the surface coat which I guess i will just smooth on with my fingers (no curved putty knife tool ?)
- lightly sand then prime with alkyd primer

I spent a little time looking a YouTube plaster videos. Some swear to dampen the area to be plastered with a mist of water - others do not ?

To replace the edge area that was chipped off by too zealous wallpaper removal I thought that I would try to sort of pipe in a line to fill the missing area (icing again !) then sand that into shape when it was fully dry.

Has anyone done this who can offer experienced advice ?

crmouldingcrack1.jpg (14.56 KiB) Viewed 1460 times

crmouldingctackchip.jpg (13.26 KiB) Viewed 1460 times

[nlswitz]

I wish I had some advice but I have no experience with this. But I love your crown and hope you have a not too hard time restoring it.

[mattswabb]

Check out this site. Maybe here is some info for you.

http://www.plaster-wall-ceiling-solutions.com

[Eperot]

very interested in this...I have the exact same issue facing me when i start my living room this summer. My mouldings are very similar. I have the idea of making a homemade "draw" blade that matches the original profile, laying on fresh plaster and pulling the knife along the mouldings to smooth out and strip the excess fresh stuff off, then sand lightly when dry. But maybe that is a terrible approach. Hopefully someone here has some firsthand experience with this.

[lovesickest]

Thanks Matt. Some good info there. I spent more time on YouTube and was relieved to see very experienced plaster restorers using a variety of tools including fingers. Those plaster repair videos are oddly relaxing - fairly slow paced, quiet, steady progress.

If you have ever wondered about the process of creating those mouldings, this shows some more complex repair/re-creation in action:

https://www.youtube.com/watch?v=hNqjZA_esJU

Repairs to the nicked edge:

https://www.youtube.com/watch?v=13xOxmxvayE

Feeling more confident about tackling this. I cannot stand one more day of those cracks.

[kelt65]

Wow I'd hire someone to do that, or at least consult with a professional. It would not be much to repair those two little things.

I love watching plaster videos . Is that plaster weld he's applied beforehand?

[lovesickest]

It says in the comments section that is what the pink stuff is - the plaster weld. I have never heard of this product before.

(Stays up till 2:30 a.m. watching plastering videos, fascinated.)

[Gothichome]

Lovesickest, if the moulding is still reasonably secure, I would be most likely to do a simple fill and profile to that area. The thing I found about moulding repair is, it gets out of control very fast, what seams to a simple task turned into a monster. Your utube links show far more work than you need to do for that repair.

[lovesickest]

Hi Gothichome.

My approach is typically moderate. I think that all that needs to happen is to carefully fill and patch, and build up the broken edge. The temptation would be to "start afresh" on a rough section - but without the skills, tools, time, resources and professional plasterer I recognize the treacherous folly of this approach.

I think I was more concerned that I would worsen the damage, or use an incompatible filler that would not bond correctly. Thankfully the areas that need work are pretty small. I will post pics when it is done.

[Texas_Ranger]

It says in the comments section that is what the pink stuff is - the plaster weld. I have never heard of this product before.

(Stays up till 2:30 a.m. watching plastering videos, fascinated.)

AFAIK plaster weld has the same job as the water mentioned in the original post. Plaster (except clay or "mud" plaster) cures chemically and doesn't just dry. For that process it needs water and if the old plaster sucks the water right out of the fresh material the new plaster won't cure and remain soft and powdery forever. Most European preservation plasterers consider plaster weld completely useless and just go with water.