Auto-dark curiosity

[DonB]

Please forgive the total noob question but humor me because I find this fascinating.

I just got me a auto-darkening helmet. I haven't sparked off an arc to check it yet but have been playing around with it nevertheless. I've found that virtually any amount of light powered by AC with stimulate darkening while no amount of light I can produce by DC will darken it. For example, a quartz halogen powered by any amount of AC power (even 5W) does the trick while a million candlepower quartz halogen on DC, or a car headlight, or even the direct light of the sun, will not. From this, it's obvious that cycle or frequency is what triggers the darkening.

Now, here's the dumb newbie part. I can weld in AC or DC mode. If light powered by AC is required to darken it, why will an arc produced by DC current darken it? Well, I'm assuming it will anyway. Otherwise the helmet would be pretty much useless.

Thanks,
Don

[zapster]

well just put it on and try it....

i dont like self darkening masks

look...theres no need to be scared.. you wont go blind if you flash yourself

i never had a auto-dark mask and have no need to ...

i suppose there are diffrent intencities of light to "set them off" but i don't trust them...

and they would not let you use them where i got certified.....


...zap!

[roverjohn]

I believe the rate of change sets them off which is why the spark of a BIC lighter does the trick. Flipping a DC light on while wearing the helmet should work also.
John..

[DonB]

Yes, I just noticed that a Bic flame darks it out and as you say, even a spark darks it out so AC has nothing to do with it. So this begs the question... if an almost non-existent amount of AC light or a lousy spark will dark one of these things out, why will a DC spotlight bright enough to fry a retina at 100 paces or a car headlight on high beam do nothing to it but make it blink for amillisecond when you pass the sensor through the beam? Man, this is weird.

Zap, I flashed myself several times yesterday. No big deal, no burn.

Don

[halbritt]

Just to reiterate something that's already been stated a few times on this forum. Most auto-dark helmets provide full protection from UV and IR whether they're functional or not. Getting flashed while wearing one of these hoods might irritate your eyes, but it won't injure them.

I know this holds true for all of the big name AD hoods, Speedglas, Miller, Optrel, Jackson, and I suspect it probably holds true for the less expensive chinese hoods.

[DonB]

Thanks Heath. Yes, I've read that. I've been reading and learning all I can around here. The way I understand it, it's the UV/IR that does the damage and everything else is about comfort. The hood I got has a base shade of 4 but continual UV protection at shade 16 and IR at 780-1400 nm whether it darkens or not. I guess 1/25,000 second is fast because if I flash myself in the face with a camera in a brightly lit room, I barely see it.

The way I flashed myself yesterday was real, though. I was playing with my first welds in 35 years and using an old hand held shield. I'd stick the rod and out of reflex, pull away the shield as I jerked the rod loose and pow, flashed. I did it a few times before I got my stupid bone under control.

The new hood should make a big difference in the quality of my welding if for no other reason than I'll have two hands to do it with.

Don

[MAC702]

Originally Posted by zapster

well just put it on and try it....

i dont like self darkening masks

look...theres no need to be scared.. you wont go blind if you flash yourself

i never had a auto-dark mask and have no need to ...

i suppose there are diffrent intencities of light to "set them off" but i don't trust them...

and they would not let you use them where i got certified.....

How long ago was that certification? That is archaic thinking and I wouldn't trust a place that didn't allow auto-darkening helmets. I consider them safer in many ways because they are down more often, cause less neck stress, easier first strike positioning and multiple-bead repositioning, which also means much faster productivity in a fast environment, especially when a large weldment has already been jigged and tacked.

I grew up using a Huntsman paper helmet. Still a great lid, but virtually all I do now is auto-darkening for many reasons.

I now have three. My first Jackson EQC Executive is almost 5 years old and still going strong. My Miller Big Window Elite is my favorite still after getting it 6 months ago. I also won a free Arc-One Hawk from this forum. I've been trying to use it often to give it a good eval. I've learned that I REALLY like my large lenses on the other two hoods. And the Arc-One will not darken when doing GTAW. At least not from my Maxstar inverter at DC 130A. My apprentice, however, has picked it as his favorite helmet for GMAW. He loves the no adjustments or ON switch.

[WillieB]

I received an auto-darkening mask as a Christmas gift about six months ago. At first, I didn't like it at all because it got too dark until I backed the control down almost to the minimum setting. I have also noticed that looking at the sun or a bright light in a brightly lit room will not activate the mask but, having no idea exactly how the sensor works, I'll venture a theory: A welding arc (or the flash of a O/A igniter or a bic lighter) activates the lens because it is significantly brighter than its surroundings. I also weld AC and DC and, as far as I can see, the thing works equally well with either mode.

Regardless, having used the auto-darkening mask for a while, I don't think i could return to the old mask, even if i wished to.

[RonL]

I have a miller elite large window. I was welding outside last week. Before I struck an arc I checked the helmut by taking a quick look at the sun. Darkened every time.

RonL

[smithboy]

Here is something I don't think anyone has mentioned. A lot of these high powered halogen lights have UV filters on them to keep from burning the crap out of you. I have several around the house and they all have a glass lens with a warning written on them NOT to remove the glass because of the excessive UV radiation it produces without the lens in place. They produce a lot of UV as compared with a regular incondescent bulb. However, it may be that all of the UV is being filtered out of the light before it gets to your helmet from these sources.

[zapster]

How long ago was that certification?

1992

i guess to each his own
i personally dont like them...

...zap!

[DonB]

Good point Smithboy but the fact is, I can't find a DC powered light of any sort that will darken the lens for more than an instant. No LED flashlight, conventional flashlight or any type of car light, even an old sealed beam. It will flash dark when the beam hits it at a certain point or a certain angle but there's no way to hold the dark. It also won't darken in the sun unless I pass my hand in between the sun and the sensor and then it will only flash dark. Doing this with a DC light source will also make it flash dark but again, no way to hold the effect. OTOH, I have yet to find an AC powered light source or spark or flame that won't dark it out and keep it dark as long as the sensor is facing the source. I guess it's just an odd mystery or this new sensor is smarter than I can give it credit for.

The important thing is it works perfectly doing what it's designed to do... welding. I never see any sort of a flash at all and I'm very pleased with it.

I did the math to get a grip on how quick 1/25000 of a second really is. It's four hundredths (0.04) of a millisecond and there's 1000 milliseconds in a second. That's one fast reaction time. To put it into a monetary perspective, I think that's the same proportion as comparing 4¢ to $1000.00.

Thanks for all the input and ideas guys. If I ever figure it out, I'll post it up here.

Don

[awright]

I suppose that each manufacturer will come up with it's own control circuitry, so each brand might react differently, but I'd be susipcious that the helmet was defective if it won't darken on the sun.

I do all my welding outdoors and habitually set my sensitivity to the highest setting that will not darken before an arc is struck. Almost always the limiting factor on the sensitivity I can set is reflected sunlight off my work area or the background causing premature darkening.

I also routinely check that the darkening function is still functioning ok by glancing toward the sun.

Have you contacted the helmet manufacturer to inquire about how it should react?

awright

[prop-doctor]

i still use my old huntsman "nod an go"

[DonB]

awright, no I haven't talked to anyone yet. It was the weekend before I started playing with this thing and when I called, no one was there.

Really, there probably isn't anything wrong with it. It may just have some sort of programming to prevent it from reacting to the sun and other inconsequential types of light. I'd think this is a good thing, especially when working outdoors.

I can't imagine a helmet performing any better than this one for welding itself. I was doing a very tedious job (with the wrong rods) on a small piece today and was welding very close to my face and never got any flash.

Don

[mccutter]

check this link out: http://www.asashop.org/autoinc/jan2002/collision.cfm

[Steelwill]

The auto darkening helment I used at work would darken when I looked at the sun also. I don't know who made it but my boss bought it from napa. It works fine for welding.

[spuddown]

I usually run my speedglas on medium sensitivity and the sun doesn't darken it

[canadianwelder1]

DonB:
Two thoughts:
1) Make sure that your helmet is charged, if solar-powered, battery is good, if so powered.
2) There should be a sensitivity adjustment in your helmet.

Hope this helps.
Mike

[DonB]

Mike, this helmet is solar with 2 solar recharging 3v lithium backup batteries that are supposed to last around 6 years. The sensitivity control works nicely as does the switch to clear delay and the shade adjustment.

What I found out from the manu. tech support is the darkening by AC powered lights vs not darkening with DC powered lights or the sun has to do with a gamma ray that one has and the other doesn't. The sun is not supposed to darken the lens. Regardless, it works perfectly for the designed purpose of welding and that's what matters. I suppose it's running on a slightly different technology than the helmets that darken in the sun. It's not approved for laser or OA welding/cutting but it is approved for all arc welding processes. The list of approved uses includes SMAW, MIG heavy and light, MAG/CO², TIG, GTAW, SAW, PAC and PAW.

After adjusting for best comfort level while welding half-inch bars together with 7018 rods, I found myself using a shade of 10.

Don

[kbnit]

None of my welders will weld with a conventional helmet once they have used an autodarkener for a week. We use either the Jackson Shadow with the EQC Executive or the Speedglas 6000XL, depending on which one the welder likes better. I've used them both and find they both work well. As regards whether or not you can flash yourself with them, I had my EQC lose power in the middle of a critical weld that I couldn't break the arc on. I was GTAW on stainless at 125 amps and about 6 inches away from the arc. I continued the weld for an additional minute and a half, and even though it was BRIGHT , after about 10 minutes my eyes were fine.

[Lanmanb4]

Originally Posted by halbritt

Just to reiterate something that's already been stated a few times on this forum. Most auto-dark helmets provide full protection from UV and IR whether they're functional or not. Getting flashed while wearing one of these hoods might irritate your eyes, but it won't injure them.

I know this holds true for all of the big name AD hoods, Speedglas, Miller, Optrel, Jackson, and I suspect it probably holds true for the less expensive chinese hoods.

The Harbor Freight auto-darkening hoods supposedly meet ANSI specs .
Its on the label in the hood and in the manual ..
What exactly those specs are .. well thats another question altogether.

[Lanmanb4]

One thing I believe might be worth mentioning.
On my HF AD Helmet, After a year of use , the
shade control is a little noisey / dirty and sometimes
it will take me back to no shade. And, due to the nice
info in the group, I know it wont damage my eyes.
However, with things that I am welding .. which is nothing
critcial.. I can stop the weld process and fix..
At some point I'm sure that squirting some control cleaner in
it will fix it up just fine ..

Side note, question..... When I look up at , say for example, my flourescent
lights, and the AD darkens, I notice that the amount of shading isnt consistent across the entire lense. Has anyone else noticed that about theirs? Or perhaps its a function of " Made in China" LOL and cheap ..

Thanks for all the great info .. I am new to TIG as well and have a HF 130 AMP Power Inverter TIG .. darn thing even has lift-arc and it was not mentioned ANYWHERE in the manual LOL ... Which tended to frustate the NEWBIE TIGGER. I called their tech support and
told them, and they were very happy to add it to the tech support notes.

Take care all .. and thanks again

[383bigblock]

You guys are scaring me looking at the sun. No matter what setting I use on my auto-darkening helmet, if I even get close to looking at the sun it darkens.
I love it since I stink at keeping a steady hand when doing the helmet flip. I always move out of position. Since I don't weld for a living the auto unit helps me with that problem.

Michael

[awright]

I guess I should actually have said I look TOWARD the sun. I don't look AT the sun's disk. The only purpose is to let sunlight or sky brightness strike the light sensor on the front of the helmet and observe that the lens darkens.

Good correction. Thanks for bringing that up. I sure don't want to give anybody the idea that they have to stare at the sun to test the auto-darkening function.

awright