Will a ROP High melt a Plastic Lense?

[jasonck08]

Will a ROP High melt a Plastic Lense? I'm not building a ROP high, but building one with a similar powered 6V 20W Osram bulb, likely overdriven to 7.4v (~25W) with 2x18650's. I'm going to order a glass lens, but was wondering how long I could run it for just with the stock plastic lens? Would 30 second bursts be safe? 10 Seconds?

I'm not doing this on a mag either, but a similar size off-brand 2D light with a polished aluminum reflector.

I just want to try out my light, before the glass lens gets here...

 

[lctorana]

Yes the plastic will discolour, darken and warp.

Go to your nearest cheap shop (I think yanks call them "dime stores") and buy yourself a cheap 2" magnifying glass - use the lens out of that.

Magnifies the hotspot, and gives a beautiful result.

 

[scottaw]

If you've already ordered a glass lens and just want to see how it'll work, just use it with no lens. I wouldn't take it out in the rain or anything, but firing it up with no lens shouldn't be a big deal.

 

[jasonck08]

I think the stupid lens might be glued in or something. I'm kind of afraid of breaking it out and scratching the polished aluminum lens.

Any suggestions on how to remove it. Do you think heat is the best option? Thanks!!

 

[MikeSalt]

If you've already ordered a glass lens and just want to see how it'll work, just use it with no lens. I wouldn't take it out in the rain or anything, but firing it up with no lens shouldn't be a big deal.

Not sure about the OSRAM, but the Pelican 3854-Hi is an ultra-high pressure Xenon bulb. Failures are rare, but if it were to fail, the glass envelope could explode causing damage to the user. I would not encourage you to use a light without the window.

 

[M@elstrom]

Will a ROP High melt a Plastic Lense? I'm not building a ROP high, but building one with a similar powered 6V 20W Osram bulb, likely overdriven to 7.4v (~25W) with 2x18650's. I'm going to order a glass lens, but was wondering how long I could run it for just with the stock plastic lens? Would 30 second bursts be safe? 10 Seconds?

I'm not doing this on a mag either, but a similar size off-brand 2D light with a polished aluminum reflector.

I just want to try out my light, before the glass lens gets here...

In short bursts you should be okay (10 second), my overdriven 20w Osram hasn't even melted the stock plastic reflector (using said short bursts)... the O/D 55w killed the reflector and deformed the lens even only on short bursts, I shouldn't have been so impatient LMAO


As for getting it out... pierce the lens and extract it with whatever devices Tim-the-toolman wouldn't use and you should be safe, as the lens is most likely shoe-horned in there how do you plan on retaining the glass lens insitu?

 

[jasonck08]

I'll probably have to get a glass lens that is a tad smaller than the plastic one. I will then put a little high temperature silicon (stuff used instead of head gaskets on cars) around the edges of the glass lens and top edge of the reflector. I think this should hold the glass lens in there.

Any other suggestions on how to hold the new lens in place?

 

[Stereodude]

I'll probably have to get a glass lens that is a tad smaller than the plastic one. I will then put a little high temperature silicon (stuff used instead of head gaskets on cars) around the edges of the glass lens and top edge of the reflector. I think this should hold the glass lens in there.

Any other suggestions on how to hold the new lens in place?

What's wrong with replacing the plastic one with a glass one and tightening the bezel back down?

 

[LuxLuthor]

Here were my actual measured temps where Fluke thermistor probe was a few mm from bottom glass envelope. Remember there can be some heat buildup if in closed flashlight head, and with longer run time.

 

[jasonck08]

What's wrong with replacing the plastic one with a glass one and tightening the bezel back down?

Because if you read my posts, you would know its not a maglight, but a similar sized 2D light. The plastic lens is stuck in there quite hard it appears.

 

[Stereodude]

Because if you read my posts, you would know its not a maglight, but a similar sized 2D light. The plastic lens is stuck in there quite hard it appears.

Ooops, I missed that. I saw the ROP and assumed M*g. Kaidomain sells a 50mm AR coated lens. Will that work better?

 

[jasonck08]

Both KD and DX sell lenses, but I think I might try the magnifying glass first because I know I can get that locally and will not have to wait upwards of 7-10 days... The reflector already maks a very tight hot spot. At 10 meters its like 6" wide.

 

[Misterbean]

what off-brand 2d are you using? it comes stock with an aluminum reflector?

 

[jasonck08]

The brand is Keen Ray. It says "High Finished Aluminum Torch D2 Cell" on the package. I think it's like a Chinese brand or something. But the machining is good quality, and so is the reflector. Threads are very smooth, better than mags. I don't like the glued in plastic lens though. It was only $8. You'd usually pay $7-15+ just for the aluminum reflector!

 

[MikeSalt]

You'd usually pay $7-15+ just for the aluminum reflector!

Just a thought, if the light is so inexpensive, chances are that the reflector is pressed aluminium rather than machined. Machined examples, such as the FiveMega reflector are heatsinked to transfer thermal energy away from the bulb. A pressed reflector is usually too thin to do this job effectively, and may cause the bulb post to melt. Worse still, the intense heat at the bulb could cause the reflective surface to deteriorate.

 

[m13a8]

I was looking into making an ROP for myself, but I can't find the 6 AA to 2 D or 3 AA to 1 D battery holders! Do fivemega and modamag still make them, or is there another battery configuration I should be looking into?

 

[Stereodude]

I was looking into making an ROP for myself, but I can't find the 6 AA to 2 D or 3 AA to 1 D battery holders! Do fivemega and modamag still make them, or is there another battery configuration I should be looking into?

Fivemega

mdocod

 

[jasonck08]

I could also make 18650 adaptors good for ROP's...

Also, I have decided to get a better reflector and will be waiting probably 2 weeks for that to get to me...

While I'm waiting, I plan to mod a spotlight that originally ran off a 6v lead acid battery. I'm going to run it off 5x18650's in a custom battery holder and its going to power up a 12v 35W Osram bulb. Should put out over 2000 lumens.