UCL or Borafloat?

[jugg2]

I'm building a Mag85, and a ROP/Mag5761. Should I go with a UCL for better light tranmission, or Borafloat for better thermal shock resistance? I'm thinking Borafloat just to be safe, but does the UCL really make a big difference?

 

[IcantC]

I asked the same Q, see this

http://www.candlepowerforums.com/vb/showthread.php?t=180283

I went with Boro since my lights are used often and last thing I want is for it to be fragile. I actually have dropped my Mag twice on concrete(last was yesterday night) with BF lense and no crack or break.

 

[IcantC]

Oh just to mention I have them in my ROP high/low and one with a Malkoff drop in.

Plan to build a 5761 and use BF. MIGHT try UCL, but I doubt it.

Oops sorry should have edited original response, can't delete this.

 

[jugg2]

Thanks!

 

[WildChild]

I put UCL in my ROP as I already had 2 of those. I ran it on ROP high for 20 minutes, totally depleting the battery pack and no sign of problem with the lens. The head went quite warm. I also have 2 mineral glass lenses. If the UCL break those should be better.

 

[LuxLuthor]

For that level of hotwire bulbs, I don't think it makes any difference. IMHO, the perceptable difference for that category of hotwires between the glass is irrelevant...and more related to marketing promotion.

However, when you get into the heat from 50+W bulb hotwires, I would ONLY recommend Boro's.

 

[WildChild]

For that level of hotwire bulbs, I don't think it makes any difference. IMHO, the perceptable difference for that category of hotwires between the glass is irrelevant...and more related to marketing promotion.

However, when you get into the heat from 50+W bulb hotwires, I would ONLY recommend Boro's.

Based on comments from other users, the 24W of ROP-HI should be OK for UCL... right?

 

[LuxLuthor]

Yes, that should be fine even if left on a long time. BTW, I am convinced that some of the cracked glass lense examples we have seen are related to the metal bezel expansion/contraction with heat, because the lens is hardly absorbing any IR energy itself. Cracks are mostly seen when people run 50-100W (or higher) bulbs for a long time.

If you pay attention to the heat in your mag head, you can manage it sensibly. If it is getting uncomfortably hot to your hand, then turn off for a bit.

 

[WildChild]

Yes, that should be fine even if left on a long time. BTW, I am convinced that some of the cracked glass lense examples we have seen are related to the metal bezel expansion/contraction with heat, because the lens is hardly absorbing any IR energy itself. Cracks are mostly seen when people run 50-100W (or higher) bulbs for a long time.

If you pay attention to the heat in your mag head, you can manage it sensibly. If it is getting uncomfortably hot to your hand, then turn off for a bit.

I ran it for the full 20-25 minutes life of the battery pack and the head never went too hot to handle comfortably! It should be OK.