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I very much enjoy painting with chalk paints. The furniture paints are heavily pigmented but the distribution chains are not reliably stocked and the color choices are limited. I have started making my own paint by adding calcium carbonate to over-the-counter latex house paint. Unlimited color choices but performance deficits and incredible financial savings.

Obviously, the paint is less pigmented and more coats are needed. Sometimes the vinyl is problematic and sometimes it isn't. I can't figure out why/when that is the case quite yet. My DIY chalk paint doesn't peel off in sheets but doesn't perform the same. So I have two questions:

Is there are over-the-counter home paint that has less vinyl or no vinyl that I can use(hopefully with some cost savings); and from a chemistry / science standpoint, how is the addition of calcium carbonate impacting the vinyl. For example, it doesn't peel off of furniture but it does peel perform poorly on slick surfaces like the inside of a smooth oyster shell and other natural objects I paint. Thanking you in advance, Rachael :)

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    All paints perform poorly on slick surfaces. You have to rough up the surfaces with some sort of scuff-sand, or there's nothing for the paint to adhere to. You'll know when you've got it when the gloss goes away. My favorite scuff-sander is a 3M Scotchbrite pad (green). Dec 29, 2019 at 4:25

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Yes, it's called alkyd paint. Colloquially referred to as oil paint. It is stinky, but good performing. It's becoming increasingly hard to find, as California and the EPA are pressuring paint companies to reduce the VOC content in architectural paints (i.e. the stuff sold at home improvement stores). Sherwin Williams continues to carry a good selection of alkyds. It's also readily available as marine paint.

It's available in all the same "bases". You know about the concept of "bases" of paint:

  • White base is heavily pre-loaded with white pigment. It's for off-whites.
  • Medium base has less white pigment. It's for modest colors.
  • Deep base has no white pigment, and is for bold or dark colors. All the pigment must be added.

My concern is that calcium carbonate is a very poor choice of pigment. It is highly alkaline, like lye, and will surely damage the paint resin. It's not a very strong pigment. Titanium dioxide pigment is vastly superior, non-toxic, readily available, and will not degrade in sunlight (a rare trait today, as most color pigments are organic, and will degrade).

So you should not be adding white pigment. You should select a white or medium base and taking advantage of the pigment already in the can.

As far as slick, glossy surfaces, paint cannot stick to that. I brush-paint some very aggressive epoxy stuff, and I basically ignore windows; I come back with a bottle of Windex and a razor blade and scrape it off the window effortlessly. Paint does not stick to slick surfaces. To make paint stick, you need to scuff-sand (remove gloss, not file material away). My favorite scuff-sanding material is in your kitchen already; it's 3M ScotchBrite pads, green color.

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  • The calcium carbonate doesn't change the color of the paint and isn't added for pigmentation. It does something to the vinyl that assistant destroys some of its properties and it makes the paint chalky. Chalk paints adhere rather week to some surfaces but occasionally need a printer for slick surfaces but the DIY chalk paint doesn't not adhere to staves that formulated chalk paint normally would. Umm also still looking for a latex product so I can clean up with water. Dec 30, 2019 at 14:20
  • @RachaelDain well, my local lumberyard just slipped me something called a "waterborne alkyd". It purports to be alkyd paint, with whatever added so it will mix with water, reduce with water, and clean up with water. I don't want it, but it may be just what you need. Dec 30, 2019 at 18:31

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