Q3 lens replacement

Well, after reading all the different threads on disassembling the Q3 head, I tried it so I could replace the plastic lens. I got the bezel off with a small propane torch (I was careful not to overheat). Once I did that, I was able to get the reflector out and then the plastic lens out. I must say the stock lens was in terrible shape for only having the Q3 for a month or so. It was totally scratched up and it was actually kind of blurry looking through it.

I replaced it with a 22mm domed mineral glass watch crystal. What a perfect fit. I spent an extra couple of dollars and got a nice flat bottom, domed top mineral crystal that is pretty thick in the middle. I don't know the exact thickness in millimeters, but it is at least 2.5 mm in the middle tapering down to maybe less than 1 mm around the edges. (Sort of like the lens on the new K1 bezel, but not nearly as domed or as thick.) Once it is in the light, you can't really see the dome to it unless you are really looking for it. Total cost was $7.50 plus tax. You can get a regular domed crystal (no flat bottom) for $3.50 and a pack of 3 regular flat mineral crystals for $3.50 too. Since I was upgrading, I went for the nicest I could find. A sapphire crystal would work too, but that increases the price to over $30+. I don't want a lens that cost more than my light.

Anyway, I was very pleased with the way it turned out. I would post a picture or two, but like I said, you can not really see how nice it fits or looks in a picture. It definitely makes a difference though. It is so clear. I am now almost blind from checking it out so many times since I installed it yesterday. It appears that it did not really do anything noticable to the beam shape. It may have a little tighter beam now, but I don't have another Q3 to compare it to.

If anyone is interested, you can get almost any size and type of watch crystal from:

http://www.ofrei.com/page_157.html

They have a minimum $15.00 order requirement, but I actually work down the street from them so I was able to get around that.

OK, that is all. I just thought I would share my first modding experience with everyone.

Nice work.

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pastanley said: I must say the stock lens was in terrible shape for only having the Q3 for a month or so. It was totally scratched up and it was actually kind of blurry looking through it.

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Good job.

The stock len is polycarbonate (plastic) the stuff they make high impact safety eyewear out of.

It will indeed scratch very easily and it isn't the most optically plane (ie: flat) to begin with.

However unless badly scratched/marred, it really is clear enough that it should make virtually no practical difference to the beam brightness of the Q-III.

If the lens is badly scratched it is pretty easy to restore/re-polish it.

A good car polish normally does the trick - however if the scratches are deeper one may have to resort to a fine metal polish first, then finish with car polish..... or very deep scratches go from a polishing compound to the metal polish and graduate and finish with the car polish......

As the lens is easy to scratch - even if it is recessed well by the scalloped hood - carrying the Q3 "naked" in the pocket along with loose change and keys is probably not such a good idea.

Use the supplied pouch, if quicker "deployment" is needed then insert the Q3 lens down in the pouch, but with the flap tucked inside (exposing the tail of the Q3 for quicker withdrawal. Or use the pocket clip - although that is set too low, thus exposing way too much of the head for my tastes.

I'd be very curious to know what the light transmittance is of mineral glass as compared to a UCL lens.

UCL's claim to fame is that their lenses transmit 98% of visible light vs. less than 90% (per their webpage) for a polycarbonate lens.

I'd be inclined to think that light transmittance isn't really a value of much interest in a watch lens. So I doubt they've designed them to specifically be highly transmittive, although it may be an unintended quality by virtue of the material. My gut feeling is that there would be less transmittance at the center (read: thicker) part of the domed lens. How significantly different it would be and how the domed shape would affect it are two questions that leap to mind.

I've been looking for alternative sources for lenses for my TM-301X-3 because UCL doesn't have anything of an appropriate size presently in stock (their "Contact" page on the website makes it pretty apparent they don't want you to bug them trying to find out when/if they will be getting something in of an appropriate size either) and unless I have to I'd prefer not to grind a lense down to fit. It's my feeling that unless you have the ability to polish the edges of the lens it's going to be more susceptible to cracking from being dropped or thermal variations due to (relatively)large scratches in the side of the lens.

After all, that's how you cut glass... scratch the surface and then subject it to stress causing a controlled failure of the glass.

PASTANLEY - what diameter did you use?

Would you be willing to buy a couple of their crystals and pop them in the USPS for me? PLMK, Thanks!

twentysixtwo

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pastanley said:
I replaced it with a 22mm domed mineral glass watch crystal.


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pastanley said:
If anyone is interested, you can get almost any size and type of watch crystal from:

http://www.ofrei.com/page_157.html

They have a minimum $15.00 order requirement

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By the looks of the web page anyway, another good source of mineral glass is here .

They don't have a minimum order but do have a graduated shipping charge, $8 for orders less than $20, and going down to free shipping for orders over $100. Given their prices, it would take a lot of lenses to get an order to add up to $20 or more.

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nerdgineer said:
By the looks of the web page anyway, another good source of mineral glass is here .

They don't have a minimum order but do have a graduated shipping charge, $8 for orders less than $20, and going down to free shipping for orders over $100. Given their prices, it would take a lot of lenses to get an order to add up to $20 or more.

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Nerdgineer-

Nice find. Now the next thing we need is for someone to take a pair of dial calipers and measure the stock crystal that's in the Q3. (I'll try and measure the one in my TM-301x-3 tonite since I'm not entirely convinced these lights are as identical as people surmise). I'll also measure the I.D on the threads in the cap to know what the absolute maximum size is that will fit. maybe we should start a thread where people can input those actual dimensions on their q3's or tm-301x-3's.

That website has the flat mineral glass in 1.0mm thick and 22.0/22.1/22.2/22.5mm diameter. After studying the threads regarding lens size for the Q3 I've come to the conclusion that it's anywhere from 22.0-22.4 mm diameter. Some of that variation is probably from different versions of the light and some is probably just due to lack of adequate equipment to accurately measure the dimensions.

The domed crystal only comes in 22.0 so it's less critical in that regard.

(IMHO)

/ubbthreads/images/graemlins/blush.gif

Bitbyte,

You are totally right about the lens size - I too found the threads to state the Q3 lens was sized from 22.0 to 22.4, with a few people filing down a 22.6 lens. I did not have the means to do that so I took my chances with the 22.0 flat bottom domed crystal and it fit perfect. I figured if it was a little small, I could fashion a gasket somehow, but luckily, I did not need too.

Hopefully, the size does change too much between different Q3s. I would hate for someone to get a 22.0 mm lens/crystal because it worked for me and then not have it work for them.

I would measure the stock lens I took out, but I don't have any calipers that would be accurate enough.

I don't have a caliper but using a high quality metallic rule with half-millimeter graduation and a loupe I have measured the stock lens for my Q-IIIs: 22.0mm.

The QIII FAQ says that there were an old model with 22.7mm inner diameter, but newer models have only 22.3mm inner diameter. That explains that some people would be able to fit 22.6mm lenses while other not.

I just wanted to ask what the difference is between mineral glass and UCL glass. Is it almost the same with a branding?

ucl is antireflective coated

What with the wild popularity of the Q3, I have to really wonder why it is that FlashLightLense doesn't carry a proper direct replacement lens for it. It would certainly seem there's a market for it.

CPF'er LitFuse is offering a very reasonably priced ($3) Q3 mineral replacement lens here on B/S/T.

sotyakr,

I've found simple mineral glass lenses for $.89. The UCL lenses are water white glass with an anti-reflective coating on them. The Shott brand of glass they seem to be using gains a tremendous amount of light transmittance with the addition of the AR coating. So I'd rather get my hands on a UCL lens.

HiGB, I'll bite. What is a roguesoulII?
regards,
vhyper

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bitbyte said:
sotyakr,

I've found simple mineral glass lenses for $.89. The UCL lenses are water white glass with an anti-reflective coating on them. The Shott brand of glass they seem to be using gains a tremendous amount of light transmittance with the addition of the AR coating. So I'd rather get my hands on a UCL lens.

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It's true that the AR coating on the UCL lens will let more light through, but I don't think you'd be able to notice the difference with just your eyes. These mineral lenses are *very* clear, and are a nice way to improve both the looks and performance of the QIII at a reasonable cost. The mineral lens is like 90% of the UCL's performance at less than half the UCL's price.

I decided to buy a bunch and offer them to people who don't want to deal with the minimum order and shipping fees involved with a small order. I believe that these lenses are still a very good value at the price that I am offering them at, and they are a nice DIY upgrade to the QIII.

Peter

LitFuse,

Don't get me wrong, I'm in no way knocking what you are trying to do. In fact it's greatly appreciated.

I'm only saying that IF UCL had the lenses it's not really a major cost as comapred to many of the other addons and gadgets involved in the flashlight hobby arena. Fo rthe extra 3 or 4 bucks, I'd *like* to have the UCL lens, in it's absence, I'm certain the MG lenses you offer are a fine alternative.

Just out of curisoity, how well do the 1.0mm lenses fit? Do they require any shimming with an o-ring or anything? Or are they possbily too thick? I have'nt had a chance to pull my stock lense out and measure it with my dial calipers yet.

Thanks.

bitbyte, if there were a UCL available that I knew was of the proper diameter to fit the Q3 without filing or grinding down, I probably would have gone that route, as you pointed out, for a few bucks more.

Sorry I haven't been around to answer some of the questions here. I've been building a new house and things have been a little hectic. I'm in a temporary living situation until the new place if finished.

I'm not opposed to making some lenses for these in small quantities, and I could if all my equipment wasn't packed up and in storage.

Once I get in the new place and things settle down, I'll get things set up and start getting back in to smaller quantity lenses and custom sizes. The QIII lens is pretty easy because I can just buzz down a 22.8.

When I tested a mineral glass lens a while back (see this thread for some details), I couldn't get more than 92% out of it. This is fairly typical for a medium quality glass. Borofloat and B270 are closer to 95% (uncoated) right out of the box.

If anybody has any questions, please feel free to email me. I'll try to keep an eye on this thread, but email is always the easiest and quickest way to reach me.