HI;

I think I got myself really confused because we started talking about patching, and this grew into a plastering project for me. The areas that were low from the removed plaster, like the ceiling, I just filled back up with Kal-Kote all in one coat, so that was between 3/8" and 1/2" of plaster all at once.

Now I am starting to think that plastering is all suppose to be done in thin layers between 1/16" and 1/8", even in conventional plaster systems. Is this correct?

So did I really mess up filling in those huge thick areas with Kal-Kote all at once? Is there any worry of it having poor integrity due yo my heavy fill? In the areas with the heavy fill, the edges have turned white, but the center where it is the heaviest has stayed darker and looks more like it did when it was wet, but it is all very hard.

So even when patching, do I want to keep with thin even coats as much as possiable?

Thanks

Jamie

p.s. I think my keens wall may have dried out without setting, it is still not hard, 36 hours after I applied it. It is showing a few small hair line cracks in the surface, but not many. I am wondering if it will ever get strong enough or if I should scrape now.

 

No,
You can spread the plaster as thick as you need to without it sagging on walls or falling out of ceilings due to it's own weight.
Sometimes it takes more than one pass to get up to the desired thickness. On a patch you can use some raw gyp or something to get it to set quicker and put on a scratch coat then as soon as it it set put on a brown coat and screed it off. That way you have less wanting to drop out. It's frustrating to have a patch in a ceiling all filled out and screeded off then have it drop when you turn your back. Leave the scratch coat rough enough to get some mechanical bond with the brown coat.

I just don't think kal-kote has enough body to build out all at once.

Probably the edges are thinner so have dried more than the middle. For ease of finishing wait until they are evenly dry. it will work better for you.

Now it is possible that the white edges dried out before it set. If the plaster is hard that's fine. If the edges are soft then moisten them a little and see if they finish setting up. When plaster dries out before it sets it is soft and chalky. you can sometimes add some water back to that soft plaster and replace what dried out and it will finish setting.

Did you give your edges a good coat of bonding agent and let it dry before you started patching? The bonding agent does two things. it keeps the old existing plaster from sucking the water out of the mix creating a weak spot right at the joining and then it also helps glue the new to the old. Notice the odor of the bonding agent. Glue.

 

HI,

Thanks for your response. I did plaster bond everything, all the edges and everything. I rolled it, then went back and cut into all the little edges and cracks with plaster bonder.

I think I mixed the Kal a bit heavy, but it did manage to stay in place up there, the color is changing now, and it seems very hard and scratch resistant.

I got me hands on Raw Gysp and Alum, as we hit spring here in wisconsin, all of the garden places start bringing in that stuff that I wasn't able to find in the winter.

I thought the plaster bonder is very much like elmers glue, smell consistency.

The whole keenes wall stayed chalky and was easily mared with a taping knife. So 3 days later, we are scraping it off and starting over. I am going to re-apply plaster bonder, then scratch in a base coat of Kal-coat, then apply the Keenes, but will add some gysp to it this time. Plus, I won't lay it on nearly as thick this time.

Does that sound like a better plan?

Thanks again.

Thanks
Jamie