Will prints stick to a painted cast aluminum plate bed?

Coming from a smallish printer with glass bed, I'm building a larger printer that will have a re-purposed cast aluminum plate bed.
The plate had some previous holes in it that I epoxied flat but would like to make it look better cosmetically by painting it with flat black bbq paint.
I'll mainly be printing PLA with the occasional clear polyester filament job. I didn't have to heat my old smaller glass bed but I'm guessing I will with this larger 15"x15"x1/4" aluminum bed.
Will the prints stick to the heated painted bed and release without pulling up the paint?

it depends.

What kind of surface preparation are you going to make for painting the bed? That will make all the difference i the world as to how well the paint sticks to it. How good are you at spraying the paint? Are you going to put more than one layer of paint on? How good is the paint?

Note that unless you're doing something really weird, a printer's heated bed isn't "high heat" as far as paint is concerned. I would be MUCH more worried about the epoxy that you used to seal and level those holes. For one, epoxy is a very poor conductor, so you're going to have huge temperature fluctuations in those spots, and for another, if you were even close to hot enough to not be able to use regular enamel paint, that epoxy is going to soften. It should be better than your PLA, but it's not great material. I'd probably rather use brazing rod to fill, but that's me.

Anyway, with good surface preparation, the paint should stick to the aluminum bed, and not your print, You may or may not need something like hairspray to get the prints to stick. You should be able to do it, and have it look okay, but I really question the wisdom of filling holes with epoxy.

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MBot3D Printer
MakerBot clone Kit from Amazon
Added heated bed.

Leadscrew self-built printer (in progress)
Duet Wifi, Precision Piezo parts

Thanks, no worries on the epoxy, I'm using Fas-Weld Aluminum Epoxy which is impregnated with aluminum powder for conductivity and says it can hold up to high temps.

The cast plate only has (2) 1/4" holes I'm filling so hopefully shouldn't be an issue.

But it is fairly shiny from the mic-6 machining. Wondering if I should use an etching primer first? I primarily don't want to scratch the paint gettting the prints off if I have to use a metal spatula.

Roy paints his bed [vkingprinter.com]

I don't know if prints will stick to paint, and if they did, I'm pretty sure you'd end up tearing up the paint pretty quickly and it would look like hell in short order. I suggest you conduct a few experiments before you apply paint to the bed plate. Maybe you can find a smaller piece or aluminum to test.

You don't normally print directly onto the cast aluminum- molten plastic won't stick to it. There's usually a layer of something that prints like to stick to, such as PEI, applied to the aluminum. PEI is usually a pale yellowish color, though you may be able to get it in other colors. If you painted the bed black and put the PEI on it it would probably still look pretty black.

I like to mark the center of the bed with a permanent marker, then apply adhesive tape, and finally put the PEI on it. That lets me see the center mark on the bed through the PEI. I like to use 0.3 mm or so thick PEI because it won't be much of a thermal insulator and will last for years. If you get PEI tape that's very thin, you'll be replacing it often.

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

interesting part DD what's it for?

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

No paint of course ! Al is a pain to paint BTW.
As for the threaded holes, easy to plug them with a threaded Al rod, cut, peen than file flat.

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"A comical prototype doesn't mean a dumb idea is possible" (Thunderf00t)