Frosting hotwire bulbs with sandpaper?

void87

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Hi,

Unfortunately i don't have the possibility to get glass etching chemicals like Armour Etch because nobody sells it here or it's just too expensive (about 40$ a small bottle:broke:).
I've read that some people frosted their bulbs with fine grain sandpaper (400 and finer). Would this work with a Philips 5761 or would it explode because of the uneven surface? Any experience with sanding hotwire bulbs?
 

EvilPaul2112

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I have frosted several lamps using 400 grit sandpaper. I gently but firmly put the base of the lamp in my cordless drill, wrap a small strip of sand paper around the bulb and spin. I applied light pressure to the sand paper. It took me a few minutes of sanding until it was frosted nicely and removed all artifacts from the beam.
 

Illum

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It sounds like an excellent way to compromise envelope integrity if you have no idea what you are doing:ohgeez:

I think for safety wear some sort of faceguard when you do this:thumbsup:

the risk of explosion occurs due to uneven expansion as the lamp heats up, but I'm not sure whether its because of the uneven surface on the inside or outside of the envelope.

For info on glass etching, try here Poor man's surefire perfect beam

cheers:)
 
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cat

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I did some 5761 with a Dremel /Proxxon sanding drum. Masking tape around it because I only wanted to frost the lower part / below the filament. It didn't work well. The tool vibrated and it wasn't possible to get it evenly around the bulb (at the edge of the masking tape.)

Then I borrowed some etching fluid from a lady at work who'd had some, not used for years. Much better. It wasn't strong like the stuff you read about here - Armor Etch or whatever it's called - it took 2 or 3 times, about half an hour before it looked frosted.

You can get it there, at a craft shop; it won't be too expensivee - better than trying to sand it, I promise you.

The only point in it is if you want to use a smooth reflector.
 

scottaw

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Be careful with those 5761's the last time i instaflashed one (fully stock) the glass shattered. I would think messing wiht it would make that possibility even greater.
 

void87

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Ok, thanks for your replies.
I think i'll better leave the bulb alone until i find some etching fluid:)
 

swampgator

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I routinely frost most of my PR based bulbs with sandpaper. But these are nowhere near being high pressure. For cleaning up a 5761 I'd go with a textured reflector.
 

scottaw

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And don't forget, the 5761 is such a high-lumen beast that it sort of cleans itself up just out of sheer lumens. Even the dark spots have a lot of light.
 
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