Weld Helmet Question

A flint striker in a butane lighter works as well. My helmet, which has a sensitivity control, can be made to darken with just about any bright light if you make it change suddenly with a head turn, or a wave of the hand, or by turning the light on and off.

Personally, if I didn't have anything easy to test it with, and couldn't make it activate with the lights I had around, I'd just strike an arc and test it with that. Just turn your head enough so you don't have to look at the arc. The light from the arc should still be able to activate the helmet.

All helmets have full time UV protection built in (required by the codes I believe) so you aren't going to do much damage to your eyes even if it doesn't come on - you will just see spots for awhile if you looked at the arc without the auto-darkening activating. The plastic shields built into helmets (and many safety classes) are normally polycarbonate which not only is a strong plastic, but blocks most the UV light. Just wearing clear polycarbonate safety glasses alone goes a long way to reducing UV damage to your eyes, - add them inside any welding helmet and you are more than protected from UV damage even if the auto-darkening doesn't come on.

Yes, full time UV and IR blocking, even if the auto dark doesn't as sometimes happens when the item you're welding casts a shadow on the sensor, which is why most helmets have more than one sensor.

My ArcOne helmet (about $200) seems to responds to just about any light - Incandescent or fluorescent - if it's bright enough. It seems to respond to Incandescent easier than fluorescent lights. But I have to turn the sensitivity almost all the way up to get it to trigger on these types of lights. I couldn't for example get it to respond to the overhead fluorescent in my office, but it did respond to the brighter fluorescent lights in my basement shop just now. It also triggered from a fixture holding 3 small CF lights (3W each). But that fixture was about 12 inches from the helmet which probably helped.

I don't know how other helmets are built, but my auto darkening unit is a

3" x 5" unit that sits behind the polycarbonate safety shield. The light sensors are built into that unit behind the polycarbonate. Since polycarbonate blocks most UV light, that would mean that the sensors would not be able to trust the UV light level as an indication of when it should activate. My guess is that it's common for auto darkening helmets to have their sensors behind a polycarbonate or other type of UV shield and as such, there is probably little point in trying to build the sensor to be sensitive to only UV light.

Dad had a set of round 'black' glass goggles for his gas rig. It was mid 50's time.

Should have seen his safety glasses - in a metal box and wire screen sides and wire rim - round thick glass. circa 40's.

Mart> "Robert Swinney" wrote: (clip) Maybe I

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You're assuming any particular effort was put into tuning them to respond specifically to UV, rather than just light.

My ebay helmet cost, IIRC about $30 including shipping. Seems to work...

I think they respond to rapid changes in light level rather than wavelength. I just tried my EQC on lights around the room here. It will activate briefly from the 4' and compact fluorescents when I wave a hand over it.

More significantly candelabra bulbs on a dimmer will make it stay dark when they are at half intensity or above. A dimmed 40W incandescent bulb emits no UV and not much visible light, but they brighten and dim

120 times a second.

I was told to use Shade 5 for gas welding, 10-11 for arc. Either will fit in goggles meant for gas welding. I don't know if it's a good idea, but I like goggles with shade 10 when I'm working near a weldor because they rest on my forehead and leave both hands free. A raised helmet bangs into things.

Jim Wilkins

Here is a supplemental question. Or two.

1) What is the interval between the helmet sensing the light change (arc) and darkening. One assumes it is short enough for the eyes not to perceive the light change but does anyone actually have the figure? 2) Seeing that these helmets are available anywhere between $30 and $300, what, if anything, does one buy for the extra$$$ ?

I have been looking at these as they were coming down in price and wondering whether to get one. I use a MIG welder exclusively but infrequently and tend to do small welds with premium on accuracy. Needless to say that I find positioning of the gun and then closing the visor trying...

Delay times can vary, but have to meet ANSI standards. That means they are different but they all shut off before the arc hurts you.

The difference in price can be quality, longevity, features, and other things. It really depends on how much you use it. Some people swear by the cheap ones and say they last as long as any. Most lenses can be put into quality hoods that don't cost a lot, like a Jackson or Huntsman. It's really a matter of personal preference. Just like some people prefer a small window, and others like the large.

Steve

Different companies make different claims. I have no way to evaluate any of them.

Speaking as somebody who owns one on the extreme cheap end of the scale:

(1) a reasonably rigid helmet. Yeah, light is good, but mine seems really flimsy.

(2) controls on the outside of the damned helmet. I have to take mine off to adjust the darkness. You'd be amazed at how annoying that gets. I'd pay a lot to add that single feature.

(3) more controls. All I get to adjust is the darkness. Expensive helmets also get to adjust the sensitivity. I find mine goes off more than I'd like when I get my glove in the field of view; no idea how I'd feel if I had the opportunity to actually adjust it.

(4) more kewlness. Mine doesn't even have a logo you see from outside. Expensive ones have kewl things like looking like skulls. Probably not important, especially at the price of SYF stickers :)

People prefer a smaller window? Why? That strikes me as, at best, a "isn't worth the money for a larger one"

They quote numbers like 1/10000 or 1/5000 of a second. It's really not much of an issue. They are all fast enough to be very usable.

A lot just seems to be brand name and/or dealer. But the more expensive helmets tend to be better made and have more features. Larger viewing window sizes cost more. Adjustable shade levels tend to cost more. Adjustable sensitivity costs more. Some don't work well for low amperage Tig welding (which doesn't produce as much light as typical stick welding applications). The more expensive helmets are more likely to work in a wider range of applications. The cheap helemts might only have one light sensor. The most expensive will have 4 located around the window to minimize the odds that you can block the light from the arc getting to the sensor with an arm and still see the arc. The electronics for sensing the arc might be more advanced in the more expensive helments (just a guess on my part). It think I remember reading specs for a helmet that said it had two different types of light sensors (but I might be remembering it wrong).

Cool looking helmets with fancier multicolor paint designs cost more than the cheap flat black plastic helmets. The cheap helmets are plastic. More expensive helmets are made of other materials like fiberglass or composite of some type (I think) and are painted.

The headband is better made and stronger in the more expensive helmets. The more expensive helmets are more likely to have more adjustments on the headband and how the helmet tilts relative to the headband.

The more expensive helmets tend to quote faster switching times (but I don't trust those numbers anyway - I suspect it's mostly just marketing BS to make people spend more money out of fear of damaging their eyes).

Better helmets include a mounting bracket for an internal cheater lens (I use a 2.0 diopter magnifying lens inside my auto darkening helmet to allow me to weld with my progressive bifocals on).

That's about all I can think of.

Mine has the knobs on the outside. They seem to get hit almost every time I raise and lower the helmet making for many a time I started to weld with the darkness set way too high or way too low. I've just learned to check the setting almost every time before starting an important weld. However, the knobs really aren't as big as they should be for adjusting with welding gloves on. Bigger knobs with a more obvious shape would be helpful. But still, I think I would rather put up with these problems than have to take the helmet off to adjust it. Knobs that were stiffer and didn't turn as easy would be nice.

Mine also has a delay control on the inside of the helmet. It's a push button which sets delay on or off. It controls how long the helmet stays dark when you finish welding. Either there is no delay (it turns off the instant you stop welding), or there's a couple of second delay. I normally don't use the delay - but the button often gets pressed by accident (from puting my gloves in the helmet I guess), and I seldom bother to change it if the delay is on.

It's also got a grind mode which turns the auto-dark off so you can use it for grinding and not have the auto-dark turn on from the sparks. I find it too dark for grinding so I don't use that feature. But this is typical of the "extras" you get when you spend more.

Mine is blue. I picked it because I liked the color. :)

I haven't tried other helmets, but mine has a good sized window, but with it comes an issue. LCDs (which is what the auto darkening helmets use) have a parallax effect where the amount of darkens (contrast) is a function of the angle you look at the display. With a larger window, you can look out though the window at a larger range of angles. With my helmet, there's a very distinctive difference in the darkness between the top of the window and the bottom (maybe a lens shade difference of +- 4). So when I set the darkness, it really only works for part of the window. If I look too high, or too low, it's too dark or too light. So, the shade changes if I tip my head up and down. I end up having to tip my head at the right angle to control the darkness. It took some time to learn to control this while I was welding - if I didn't pay attention, as the weld progressed, it might move into a part of the window which was too dark - so I couldn't see well enough, or to a part too light, which would start to blind me. I had to learn to move my head correctly as I welded.

For someone use to a standard fixed shade helmet, this effect with the auto-helmets might drive you crazy at first. But, it's something I got used to and just don't think about anymore. It's all automatic now. Maybe other (more expensive?) helmets don't have the effect as much as mine does? But before butting down a lot of money for a huge window size, it would be good to try the helmet out. It's an effect that might prevent a larger window size from being as useful as you would expect it to be - at least when the auto darkening was activated (there is no parallax effect when the auto darkening is off).

I'd never go back to a fixed shade helmet personally. I think they are well worth the extra money. But at the same time, many old time welders who learned how to weld with fixed shad helmets don't seem to feel the need to change to the auto darkening. I think once you really learn to deal with the head flipping, you just don't feel you need to change. But for anyone starting out in welding now, I would advise using an autodarkening if you can justify the cost. It makes it a lot easer to learn in my opinion.

Ah, OK -- there are effects at work here besides just the size!

Some people prefer the small windows because they can get corrective lenses in the smaller sized openings. I started out on small openings, but prefer the large ones.

Steve