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ner'T'
03-13-2010, 08:36 PM
Anyone know where to find glass for my 250 MH light? I had a thin non-tempered one and surprise-surprise, it cracked from the heat. The lens is approx: 15" x 8.5".

Thanks for any input
pelle31
03-13-2010, 08:43 PM
I had to find glass as well for the bogus light that was sold to me. What you can do
is go to your local glass shop and see if they have high heat glass in stock. Otherwise
they more then likely have to order tempered for ya.
sphelps
03-14-2010, 03:06 AM
Any glass shop should be able to get 3mm tempered glass cut to the size you need, phone around and find the best deal. Some will apply a minimum charge so it could vary.
pelle31
03-14-2010, 03:14 AM
Oh yea they can get it....it will most likely have to be ordered though.
Bryan
03-14-2010, 07:59 AM
Think it has to be ordered,you can't cut tempered glass.
golf nut
03-14-2010, 10:37 AM
Anyone know where to find glass for my 250 MH light? I had a thin non-tempered one and surprise-surprise, it cracked from the heat. The lens is approx: 15" x 8.5".

Thanks for any input

You might want to check for something special about the glass, simply replacing it with regular glass that you get tempered may not be that simple.
mr.wilson
03-14-2010, 03:57 PM
You might want to check for something special about the glass, simply replacing it with regular glass that you get tempered may not be that simple.

HQI lamps have a UV filtering quartz outer glass, so you don't need to have a quartz glass lens. You needed a quartz lens with the old Osram Powerstar lamps.
sphelps
03-26-2010, 04:52 PM
HQI lamps have a UV filtering quartz outer glass, so you don't need to have a quartz glass lens. You needed a quartz lens with the old Osram Powerstar lamps.
I was under the impression the HQI or DE bulbs don't have the UV filtering outer glass and require tempered "low emissivity" glass. It's the Mogul or SE bulbs which have the UV filtering outer glass and don't require any additional requirements for a glass shield.
fencer
03-26-2010, 05:21 PM
They can be found in any glass shop ( 20 / pane). Actually DE have the UV filter. The extra glass shield is to protect you from an exploding DE.
Marlin65
03-26-2010, 05:29 PM
My Mh have Low E tempered glass on them and are DE.
sphelps
03-26-2010, 06:48 PM
Actually DE have the UV filter. The extra glass shield is to protect you from an exploding DE.
That doesn't sound right, why would a DE bulb be more likely to explode?
DE lamps do not have the large outer envelope typically found on single-ended lamps that is used to limit the lamp’s UV radiation. Double-ended lamps require an additional safety glass to be installed in the lamp’s fixture in order for them to be safe for your tank’s inhabitants.
http://reefkeeping.com/issues/2007-03/sj/index.php
fencer
03-26-2010, 06:56 PM
DE bulbs run under pressure....I can't remeber but I think it was greater than 50 psi
brizzo
03-29-2010, 08:41 PM
Speaking from experience cooking everything in my tank ... DE halide bulbs are NOT UV shielded; except the ones from Coralife (or so they claim).

Personally I was unable to find a glass shop that could get a piece of tempered glass that small. Each glass shop I checked with said "no problem, but it's a minimum charge of $30 for any tempered glass", then would get the phone call "sorry we cannot get tempered that small". The explanation was due to the small size of the glass not being able to travel through the furnace that does the tempering.

But, if you do find a shop that is able to produce; please let me know :mrgreen:
Marlin65
03-29-2010, 08:59 PM
Your right they have a min size but it is 6"x12"
I can get them.:wink:
brizzo
03-29-2010, 09:12 PM
Your right they have a min size but it is 6"x12"
I can get them.:wink:

I was looking for a piece roughly 4.5x8" for a coralife 150w clamp on pendant. The solution was having a glass top made for the tank, our of regular 1/8" glass.
sphelps
03-29-2010, 10:40 PM
I was looking for a piece roughly 4.5x8" for a coralife 150w clamp on pendant. The solution was having a glass top made for the tank, our of regular 1/8" glass.
I'm pretty sure I can get that done here for you if need be. I had a couple pieces done a few months ago that I recall being around the same size. If you want me to look into it just shoot me a PM.
pelle31
03-29-2010, 10:50 PM
At my Local glass shop all they needed was the measurement and they would have to order
the piece in. They told me that wherever they manufacture tempered glass all they have to
do is make a mold. They phoned the manufactuer while I was standing right there and they said it was no problem as long as they had measurements.
Marlin65
03-30-2010, 04:24 AM
To temper glass they heat regular glass (Float glass) red hot and then cool it with 500 HP fans on each side to cool it down quick. Just like heat treating steel.
The reason they have a minimum size is that most of the small pieces don't survive the tempering process. (They explode)
I don't know about AB but here in BC there are only three places that temper glass and none that do bent temp.