DIYbanter - View Single Post - Having a problem seeing the weld pool with very low currents

Curt Welch

wrote:
I'm currently TIGing some thin stainless (0.55mm) sheet and this
requires very low currents.

The problem I'm having is that my auto-helmet only goes down to DIN 9
and it seems way too dark.

Mine goes down to something like 5 I think. You could always shop around
for a new autodarkening filter that goes lower.

I don't really want to go back to a fixed filter (and even if I did,
none of the local welding stores have anything lighter than a DIN 9
anyway) so I've tried using a spotlight to illuminate the work --
which means the auto-helmet simple goes dark anyway (damn!)

Maybe you could try your sunglasses in combination with a shade 3 face
shield? I use a shade 3 face shield for oxy.

I think the shade numbers are designed to be additive so if you could find
low value face shields that add up to about what you think you need you
might be able to overlap them and make it work.

Is DIN 7 or DIN 8 an uncommon shade or something?

I've not tried shopping for shields in that range, but most arc work is in
the 9 and above and gas is 5 and below so those numbers probably are hard
to find.

I tried using a pair of sunglasses but they seem to be only about a 5
(I estimate) and don't shade enough and my oxy goggles seem to filter
out the wrong part of the spectrum because it's still very bright -
but also very green :-)

Any ideas folks -- or do I just hunt down a DIN 7 or 8 from somewhere?

And yes -- it's a pig of a job doing a good fitment for a long butt or
lap weld with metal this thin. I'm using a chill-bar behind the seam
but trying to do a fusion weld on a 2mm lap still causes problems now
and then when the two sheets aren't quite touching.

I also have to do a lot more practice on filling holes (how did they
get there? :-)

I've had lots of practice with that!

--
Curt Welch http://CurtWelch.Com/
http://NewsReader.Com/