Some of you might find this interesting, others may already know. A while back I decided to buy a new lens for my helmet, just the clear one for the
front (it's an auto darkening helmet). I thought I'd spend a little more on a glass one, rather than the plastic one that was in there.
Turns out that glass is not a good option for a welding lens, as the spatter sticks like the proverbial to a blanket. The much cheaper plastic is
better as it doesn't stick as much. I thought the glass would be better as it would resist melting, turns out I was wrong.
So if anyone wants to replace their helmet lens, go for plastic.
Yeah you don't want glass for your outer lense.
quote:
Originally posted by Davey D
Yeah you don't want glass for your outer lense.
Its all to do with heat dissipation, and its the same with optical lenses in safety specs. Any sort of plastic ( and there are quite a few different
materials) is a lot safer in the event of an impact injury, eg a flying lump of metal whilst cutting or grinding. It absorbs the impact by dissipating
the energy across the material due to its softer make up. Downside is it scratches far more easily. Good thing is its about half the weight or
less.
As glass is much worse at transmitting heat than plastic, when welding spatter hits it, it tends to "stick" due the heat being help very
locally and it literally melts a small indentation in the glass.
Plastic however, takes the heat out of the spatter very quickly, due to its greater heat transfer properties, so generally, the particle cools very
quickly and falls off before it can bed into the material. Plastic for those in the industry every time!!
Every industrial place I have worked in always used glass, since I have used glass for so long I prefer it now, soon I may have to change as I'm
down to my last glass now
Maybe I'm to long in the tooth, I bought an auto darkening helmet didn't like that either, gone back to the classic style helmet
David
To qualify "Industry", I meant the optical industry, as opposed to manufacturing and engineering.
I ordered a couple of replacement lenses from Toolstation, plastic this time. They didn't have them in stock but I could have them delivered to
my home address with no postage costs, just the £1.37 each....
They arrived this morning, and they've put a catalogue in with the order. So instead of a 40p stamp to post two thin pieces of plastic,
they've paid a couple of pounds to send me a catalogue in a jiffy bag.
And businesses say they are struggling...
quote:
Originally posted by Slimy38
I ordered a couple of replacement lenses from Toolstation, plastic this time. They didn't have them in stock but I could have them delivered to my home address with no postage costs, just the £1.37 each....And businesses say they are struggling...
