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Thread: U-v

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    U-v

    Does that Sheep dip U-V coating or the "Factory U-V" coating we use provide adequate UV for welding? If we believe the claims, 100% is 100% right?

    Particularly can we sheep dip the goggles that say: "Does not provide adequate protection for eletric welding!" and make them adequate? Do polycarbonate lenses (another claimed 100%) provide adequate protection?

    Chip

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    Bad address email on file dfisher's Avatar
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    Chip,

    Welding lenses usually are very VERY dark. Their primary function would be to block infra red light rather than UV.

    Just ask any welder what a corneal burn from the IR rays of the arc feels like.

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    Manuf. Lens Surface Treatments
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    Re: U-v

    chip anderson said:
    Does that Sheep dip U-V coating or the "Factory U-V" coating we use provide adequate UV for welding? If we believe the claims, 100% is 100% right?

    Particularly can we sheep dip the goggles that say: "Does not provide adequate protection for eletric welding!" and make them adequate? Do polycarbonate lenses (another claimed 100%) provide adequate protection?

    Chip
    The ultimate lenses for welding are MINERAL, green colored NEARLY BLACK.
    Plastic lenses do have one plus. They do not get pitted when the sparks are flying. They do not give you full protection. But the real glass lenses give you the maximum protection you can get.

    I would like to add that properly treated plastic lenses are usually better, when treated in a good aftermarket solution than in factory coatings. If you want to know why I can answer that.

    For welding you want protection form Infra Red, UV as well as the light.

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    sub specie aeternitatis Pete Hanlin's Avatar
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    Just curious, but I thought the primary function of a welding shield was to protect against UV and the intense light. The "burn" that you get from unprotected viewing of arc welding is SPK (superficial punctate keratitis), and is a direct result of UV, not IR, energy.

    For IR protection, glass blowers usually use lenses treated with beryllium. I was under the impression that these lenses are usually glass, but I could be mistaken.
    Pete Hanlin, ABOM
    Vice President Professional Services
    Essilor of America

    http://linkedin.com/in/pete-hanlin-72a3a74

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    Pete:

    Trust me you can also get a very serious Retinal Burn, just like looking at a solar eclipse.

    Chip

    My point in my origional posting was: Our 100% UV coating probably ain't 100%.

    Chip

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    Master OptiBoarder Jeff Trail's Avatar
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    Chip,

    You can get it to 100% BUT (always have to have a BUT in there somewhere) UV that is induced into a lens via a tinter is only imbibed into the surface, and as time goes by it disapates back out of the lens (turns into a gas and goes away),maybe not completly but it does begin in around a few months to break down..this is the reason you NEVER want to dip coat a lens in UV if you are going to AR coat it..as it returns to a gas form it causes the stack to shatter..
    You would be far better off to get a UV lens from the factory where the uv is throughout the entire lens..retinal burns is the greater problem and the bigger worry than blocking infra red spectrum.. I also would prefer to have the "plastic" version over glass as far as pitting...


    Pete,

    It is glass, you are right :-)


    Jeff Trail

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    Manuf. Lens Surface Treatments
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    Jeff Trail said:
    You can get it to 100% BUT (always have to have a BUT in there somewhere) UV that is induced into a lens via a tinter is only imbibed into the surface, and as time goes by it disapates back out of the lens (turns into a gas and goes away),maybe not completly but it does begin in around a few months to break down..this is the reason you NEVER want to dip coat a lens in UV if you are going to AR coat it..as it returns to a gas form it causes the stack to shatter..
    You would be far better off to get a UV lens from the factory where the uv is throughout the entire lens..retinal burns is the greater problem and the bigger worry than blocking infra red spectrum.. I also would prefer to have the "plastic" version over glass as far as pitting...
    I beg to differ, there should be no BUT. Everyone can learn to do things right.

    A PROPERLY done UV in a tinting process is there to stay and does not adhere just to the surface.

    The chemical used for this purpose is called benzophenone which will penetrate right into the lens pores and re-crystallize and stay there for the life of the lens. It's efficiency becomes even better as time goes by.

    If you use a 60 second UV, the UV absorber will not penetrate into the lens pores and re-crystallize, and just cling to the surface and eventually be wiped off by lens cleaners.

    There are problems when the lens is AR coated but do you actually want AR coated welders glasses?................... Is that not pushing sales a bit far?

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    Master OptiBoarder Jeff Trail's Avatar
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    Chris Ryser said:
    A PROPERLY done UV in a tinting process is there to stay and does not adhere just to the surface.
    The chemical used for this purpose is called benzophenone which will penetrate right into the lens pores and re-crystallize and stay there for the life of the lens. It's efficiency becomes even better as time goes by.
    If you use a 60 second UV, the UV absorber will not penetrate into the lens pores and re-crystallize, and just cling to the surface and eventually be wiped off by lens cleaners.
    Chris,

    You can disagree as much as you like :) BUT (there I go again) how many opticals do you see that use anything other than a quick dip style of UV'ing? The VAST majority of opticals use the quick dip method and nothing even close to what you mentioned, you would LIKE them to do it that way since that is what you do,isn't? Push after market product (tints etc., etc.), but than again how many times have YOU walked into an optical and they are doing it the other way? Probably 50 to 1 would be a decent number.. which was why I also mentioned the UV/AR problem, not that I would ever sell someone in Chips situation an AR..give me more credit than that..sheesh, I just mentioned it for someone else that might read the thread and pick up on UV/AR problem....
    You might as well accept as I have that most opticals are going for the cheaper quick dip method, and I think 60 seconds is even stretching the time they leave it in the batch
    I'll bet money that in every account I have NOT ONE of them are doing it other than a "quick dip" ..so as I said, if you want the best way and are NOT set up to do it other than the quick dip method than you NEED to buy a factory UV'd lens if you want the best result..
    I learned long ago there is always the "best" way of doing it, than there is the most widely used way of doing it...usually they are NOT both the same way...

    Jeff "gee, I guess I must really be just some dumb lab rat" Trail :)

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    OptiWizard
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    Unless you're prepared to test the lenses to very specific transmission limitations established by Z-87, and to stand behind that testing in a court of law, I wouldn't even consider it.

    There are NO Rx lenses suitable for actual welding, not even braising. The UV attenuating clear lenses are useful in a welding environment to protect against flash but not welding.

    Point(s) of interest.

    Glass blowers use didymium lenses to protect from sodium flare. Real wierd transmission curve.

    Welder's Flash is caused by UV; it's really a sunburn. Clear poly (and others UV attenuating lenses) will protect against that but obviously not IR or intense light.

    Poly lenses are generally used for welding with the appropriate tint numbers marked on the lenses per Z87.

    Glass lenses "pock" easily when hit by welding splatter which may effectively render them useless against impact. Be sure to pass this on to any customers using these lenses.

    Poly and CR-39 lenses are not as effected by splatter.

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    Bad address email on file dfisher's Avatar
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    I've done a bit of searching and I can only find limited information on these lenses. Most sources only recommend "shade numbers" for welding. Does anyone know what these shade numbers represent in terms of visible, UV and infra-red?

    From what I've read so far, I really wouldn't to get into the liability and regulatory issues on this one.

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    Manuf. Lens Surface Treatments
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    Dont get exited..........................

    Jeff Trail said:
    The VAST majority of opticals use the quick dip method and nothing even close to what you mentioned, you would LIKE them to do it that way since that is what you do,isn't? Push after market product (tints etc., etc.), but than again how many times have YOU walked into an optical and they are doing it the other way? Probably 50 to 1 would be a decent number..

    You might as well accept as I have that most opticals are going for the cheaper quick dip method, and I think 60 seconds is even stretching the time they leave it in the batch

    I'll bet money that in every account I have NOT ONE of them are doing it other than a "quick dip" ..

    Jeff,

    You don't have to get exited over this.

    But where is the conscience of the optical trade when the opticals massacre a good concept of being able to supply top quality protection to the consumer, just to save some money and time?

    What about the suppliers that make them opticals believe that they are buying the real stuff.

    Who is the one that buys badly done UV jobs? THE CONSUMER.

    If it's 50 to 1 that are doing it, as you say, it should be time that these opticals need some waking up. If your figure is close to the fact, this would be a very sad situation.

    Of course I am pushing after market treatments, BUT they should be properly done and not the fast buck way. Even by doing it right with quality products that cost a little more there is still some good profits to be made.

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    OptiWizard
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    For dfisher.

    The tables noting the shade numbers and REQUIRED transmissions are in ANSI Z87 (current edition).

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