- Thread starter expat
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There's a recognised table issued by ISO (or some international standards body) giving the recommended shade for various processes and currents. The filter numbers are also an international standard.
There's a copy of it on page 28 of the Speedglas catalogue.
http://3m.richfx.com.edgesuite.net/catalog/media/European_Speedglas_Version1/?rfx_page=7
There's a footnote which says the table is only a guide and you may need to go up or down a shade depending.
So, coming out with a simple statement, 13 for MIG and 11 for stick is incorrect and 13 is only recommended for very heavy current MIG.
Now I think I'm right in saying that at whatever strength, the filters stop all the UV and IR, and the strength refers to the amount of visible light it cuts out, so you're really selecting one which allows a comfortable amount of visible light through.
There's a copy of it on page 28 of the Speedglas catalogue.
http://3m.richfx.com.edgesuite.net/catalog/media/European_Speedglas_Version1/?rfx_page=7
There's a footnote which says the table is only a guide and you may need to go up or down a shade depending.
So, coming out with a simple statement, 13 for MIG and 11 for stick is incorrect and 13 is only recommended for very heavy current MIG.
Now I think I'm right in saying that at whatever strength, the filters stop all the UV and IR, and the strength refers to the amount of visible light it cuts out, so you're really selecting one which allows a comfortable amount of visible light through.
knoba
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I believe it's 9-13 for arc processes. This variation between the two settings, or "ambiguity" (what it may seem to be at first), accounts for the difference in the machines' power settings, relating directly to the arc intensity, for different arc processes. I usually estimate the power settings to the shade setting;
If MIG'ing at 40 Volts - I'll use the lowest shade setting #9
If TIG'ing at 140 Amps - I'll use the highest shade setting #13
If Arc welding at 90 Amps - I'll use a moderate shade setting #11
Another factor will be "how long do you weld for?"
If one is welding all-day, every-day, then the shade settings will become more critical.
I was TIG welding between 80-110 amps for 4 hours yesterday on bright aluminium. The shade setting was #9 (too low, I know, but I didn't think I'd be welding for that period of time). By the evening I could feel my eye's just weeping slightly... Was there a higher compounded intensity exposure from reflected UV's off the ally? If I had only been welding for 2 hours, then I would have felt no ill-effects at all.
My eye's are fine this morning, after a good nights' kip, and ready to roll again...
That's my take on it, anyway. Not official, just a bit of common-sense and a little experience. I've had bad 'arc-eye' a few times as a child - it's not a sensation one forgets. I've got a good lid too...
...I've heard that too. Frankly, I'm not completely sold on it.
If MIG'ing at 40 Volts - I'll use the lowest shade setting #9
If TIG'ing at 140 Amps - I'll use the highest shade setting #13
If Arc welding at 90 Amps - I'll use a moderate shade setting #11
Another factor will be "how long do you weld for?"
If one is welding all-day, every-day, then the shade settings will become more critical.
I was TIG welding between 80-110 amps for 4 hours yesterday on bright aluminium. The shade setting was #9 (too low, I know, but I didn't think I'd be welding for that period of time). By the evening I could feel my eye's just weeping slightly... Was there a higher compounded intensity exposure from reflected UV's off the ally? If I had only been welding for 2 hours, then I would have felt no ill-effects at all.
My eye's are fine this morning, after a good nights' kip, and ready to roll again...
That's my take on it, anyway. Not official, just a bit of common-sense and a little experience. I've had bad 'arc-eye' a few times as a child - it's not a sensation one forgets. I've got a good lid too...
...I've heard that too. Frankly, I'm not completely sold on it.
Sparkey
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Yes, that's why most auto helmets have a fail safe shade setting, (for speedglas i happen to know this is shade 5)
You will be protected from arc eye, but it depends on you, i think what is comfortable for you...for example my mate at work will be mig welding with shade 9, but would i use shade 9 my eyes would start weeping soon and become irritated....I'm always using shade 11 for around 200 amps...i must add that my eye sight is better than his'...
You will be protected from arc eye, but it depends on you, i think what is comfortable for you...for example my mate at work will be mig welding with shade 9, but would i use shade 9 my eyes would start weeping soon and become irritated....I'm always using shade 11 for around 200 amps...i must add that my eye sight is better than his'...
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Sparkey
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knoba
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...that makes a lot of sense. Thanks, Sparkey!
If the battery ever fails on my lid, at least I can use it for plasma cutting.
Sparkey
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...that makes a lot of sense. Thanks, Sparkey!
If the battery ever fails on my lid, at least I can use it for plasma cutting.
Yup...or hang it on the wall for decoration....
to you too! 