I agree with Les on painting.
At times it is appropriate to paint the inside of a
fixture - especially if older and paint flaking or its rusting inside. If an aluminum
fixture, perhaps a light scraping or
wire wheeling with sanding to provide tooth to the paint than a touch of high temp. to reduce stray light as needed if needed. For a steel
fixture, especially stamped sheet steel, it's possible unless treated for that rust to work it's way to a structure problem or hole in the
fixture problem - gotta fight the rust. Have seen fixtures near rusting
thru in the past, this especially from inside out.
First step, remove as much as possible of the rust or flaking paint by way of sanding and scraping. Than the question of if one should rust reform - given it's normally low temp. paint this rust reformer or high temp paint over the rust in a way that might not kill off the rust. If out of the main heat I might do rust reformer first say after the
gate only if needed, or on the
yoke if it can't be just sanded, than high temp overcoating but overall if you have a good coat of high temperature paint and most of the flaking paint off plus rust sanded down, the high temperature paint even engine paint in possibly a better quality product I
stock but have not noted a real difference on, should work sufficiently to stop rust. It's a concept to do rust reformer than high temperature paint but as a concept I don't think so much of that in reality of working. Thinking skip the rust reformer step once sanded and chipped.
Tried the rust reformer paint with high temp. paint over it before without problems but I don't think it would work so well in 500w or over situations. More or less, if you have a good coating of high temp. paint it should stop the rust sufficiently - this especially with sanding in not needing the rust reformer overall.
One primary thing often noted for painting is older paint on steel fixtures basically rusting under the paint in allowing the paint to flake. This byond flaking of aluminum fixtures where chipping and sanding to feather an
edge plus provide a tooth for the new paint to stick to is probably appropriate. On a steel
fixture rusting but probably old and or antique, does one remove the origional paint in saving the
fixture or keep the origional paint? Does one just chip off what's flaking, or remove anything that's beginning to flake if not all the old paint?
For aluminum castings that have flaking paint, I feel it absolutely necessary to before attempting to paint sand them. Short of sanding in giving some tooth to the metal for the new paint to stick to its going to chip again. Your next coat of paint will likely
peel off with time no matter the
thickness of layers or temperature
rating unless on aluminum you give tooth to that paint to stick to - this unless special paint designed around this sticking to purpose. Do this with barn doors all the time especially.
For steel parts, sure scrape and sand or
wire wheel the
yoke so all paint's gone unless above that paint is a manufacturer decal or sticker. In that case, work around it as best possible even if for the most part rubbed off. Even for such decals before painting, don't apply even painters tape directly to the decal - still too sticky. Stick the tape to your blue jeans a few times in picking up some lint a few times before attempting to put tape above an old sticker or decal on a
yoke or
fixture.
After that, it's a
yoke, paint away.
Fixture itself, how much is a olive drab
Altman 360 worth if it's paint is mostly gone or chipping over one that's been re-painted but is in workable cared for condition or shape? Sure if in good condition perhaps a few flakes on the aluminum leave it alone in chipping what's needed but only as much as needed, but a
fixture that will eventually rust
thru... verses one that's painted... save the
fixture in my opinion but it would depend on condition. Once had some three color Century 4.5x6 fixtures I was working on. Believe I left the body/
pineapple part alone in origional color, the
gate assembly for some reason needed a grey primer and the
lens train a high temp. paint. Or something like that in just leaving them in how it worked out to be three color fixtures, but ones once serviced still in use and if not by paint, at least would go another ten years before they needed more attention. Don't remember how they turned out three color but that's how it ended up for them and it was simple and honest. Perhaps the caps instead of the
gate assembly was the third color.
None the less, after the saving of the
fixture concept - and how agressive to get in removing old paint gets done say if it might flake or easily comes up, to paint or not paint is more a question of use. Are you preserving an antique, or fixing something for your inventory?
If preserving an antique, perhaps it might be needed to remove and paint as needed to prevent it from rusting
thru. If fixing a
fixture still in the inventory, perhaps than it don't matter the origional texture of the paint on the
fixture and one should remove what's needed and re-paint not so much to match but so as to make the
fixture look quality and cared for.
Be it the client, talent or audience, they don't know what's modern or ancient, they do know what looks hack on the other
hand. Even on an aluminum
fixture, wouldn't want any chipped off paint - just looks unprofessional. On the other
hand for an antique, perhaps if not an overall thing on the aluminum casting, perhaps that's fine or even making that aluminum casting natural in removing all the paint.
Beyond that, for an antique, make it match as best possible or make it the
conventional norm semi-gloss or
flat black if needing to be painted. Don't make an antique gold or some similar silly thing as I have seen at times. Were it a prop antique, I might look into a texture paint below the high temp. normal paint colors. Texture paint as normal to antiques is hard to reproduce but can be done with some looking.
On
reflector paint for scoops, once did my 10" scoops with silver spray paint. Long gone in sold off. Refinished some others in the past as if a
clip light work light by way of removing the paint and buffing + shining that surface with lots of work in making a
reflector. Got a 1920's Ovallite with Dracula blood in it that someone at some
point also painted silver. Wouldn't do any such thing for a
scoop these days, this especially for an antique.
While I know most scoops are polished spun aluminum in
reflector, and that reflects better than paint, Fuch's in the 1920's specifies white
ceramic paint for such a
reflector. That's what I would do for a proper or antique these days. This in a debate about if the
scoop is to be soft reflected light or a
reflector assembly. Even remember scraping such a coating off fixtures in the past to make them reflective. Still, and even if frosted lamps as the source of lamp in such a wattage wasn't available back than, a question of what softness of light one wants for the
scoop as opposed to light output.
Overall in concept a more diffuse source of light from a matt
ceramic reflector, this especially if frosted in source will be more soft than that of a
reflector and even
clear source in light. That's a minute detail but one that might be detected in how one does a
reflector. In general however, if doing a
reflector, matt white if not
ceramic white veses as opposed to painted
reflector spun and polished
reflector I think reflects more light.
Powdercoating. Weird process, our other ME as it were in the old shop hooked up a stove at one
point and was doing so with his own use of powder coating painting materials. Worked out well but very specilized and or for doing so in an oven, something that takes education in how the process works but can be done. On the other
hand, powdercoating isn't as expensive as assumed. More a question of if you have time to wait and say that color is in use, or if in bulk, it's a little cheaper to have done than if this is only say one
fixture to be done. Powdercoating isn't persay a question not reasonable to look into.