Some glass lens questions...

[Guy's Dropper]

If I were going to do some sort of high high power incandescent Maglite modification, would I need to use a Borofloat® Lens, or could I get by with a UCL® Lens? I know that incandescent bulbs can get hot, but do they really get hot enough to melt glass?

Also, I was wondering if glass lenses are practical on general use lights, or do they break easily? I know it's not a problem with the small led lights, but what about a larger Maglite-size lens? Do they survive drops?

Can't edit thread title? I misspelt lens.

 

[Lumencraft (Matt)]

Re: Some glass lense questions...

Hey Guy's Dropper,

What lens will depend mostly on what bulb. For the very high powered lights Borofloat is what I most commonly use. UCL are great for leds, and they will work for incans. I have a maglite with a philips 5761 bulb rated at about 1400 bulb lumens that I use an ultra clear in. However I would say they are a bit more fragile. Any thing hotter than a WA 1185 or the 5761 you should be using a Borofloat (imho).

When you edit click "go advanced" and you will be able to edit the title.

 

[Justin Case]

Re: Some glass lense questions...

"Borofloat" glass is just borosilicate glass that typically is made using the "float" process (molten glass floated on liquid tin). It's basically Pyrex, with the main advantage of low thermal expansion (thermal shock resistance).

It is very doubtful that you are going to melt any sort of glass window in a flashlight with an incandescent lamp.

If you hit glass, it can break. It's glass. It may not break, but it most likely isn't as tough as a plastic window. But glass will stay much more scratch free and clearer over time and have better light transmission right off vs plastic.

 

[Guy's Dropper]

I thought most glass was made using the float process. Are you saying that UCL is not?
I'd expect it to break if the glass itself was hit, but what about the shock of the flashlight hitting the ground?

 

[RyanA]

Meh I've brought a few hotwires to work here and there. I've even dropped a few in the parking lot. No broken lenses yet. Maybe if you threw one or heated it up and rapidly cooled it. Otherwise you'll probably be alright with normal use.

 

[Justin Case]

There is glass pressing, glass drawing, glass blowing,....

I have no idea how UCL is made but I would imagine that the float process is the most likely possibility since we are talking about flat glass.

I've dropped a SureFire L4 with glass window onto concrete from waist height and didn't have breakage. The window, however, is probably smaller in diam than your Maglite application. The Mag also probably weighs more.

 

[Lumencraft (Matt)]

Re: Some glass lense questions...

"Borofloat" glass is just borosilicate glass that typically is made using the "float" process (molten glass floated on liquid tin). It's basically Pyrex, with the main advantage of low thermal expansion (thermal shock resistance).

Thanks Justin,

I like that little knowledge nugget you threw out, I had never hear that before.

 

[Justin Case]

So in fact, flashlightlens.com has information that mirrors what I wrote:

http://www.flashlightlens.com/str/index.php?app=ccp0&ns=display&ref=about_glass