Learning to weld with a non-aircraft project

Paul wrote:

The lense in these shields is often so dark that you literally cannot
see your work with the shield down, so you get yourself arranged with
the shield up, and configured so that it will drop down over your face
with a nod. Then you get set to weld, hold you hands where they need
to be, nod your head and begin.


I bought one of these electronic units that allow you to see your work, then
darken as soon as you strike an arc.

A super investment.

Cheers:

Paul
NC2273H

Amazing how bright that 1/20000 second can be, isn't it.

Rihcard

On Wed, 24 Mar 2004 00:23:21 -0500, "Morgans"
wrote:


"Corky Scott" wrote in message
...
On Tue, 23 Mar 2004 09:55:04 -0600, Russell Kent
wrote:

Corky,
At the risk of sounding completely naive (I know nothing of welding)
couldn't you replace the lens/filter in the full face shield you were
using
with a TM2000 lens/filter?

Russell Kent

Ah, sorry, I did not describe the face shield properly: It's a full
plexiglass shield, not a face shield with a little window in it.

Yes, had it been the face shield with the window in it, I could have
replaced that window with the tinted glass from Tinman. But I would
have experienced the same problematic cutting off of the lower field
of view that I need for proper focusing.

Using the plexiglass face shield, you don't have to worry about
cutting off your field of vision, the entire shield is see through
tinted plastic.

Does that explain things better?

Corky Scott

Why don't you get a pair of custom bifocals? You can get them with the
bottom 2/3rds of the lens the strong part, with just a bit over the top for
distance vision. I have a pair like that, and the difference is remarkable.
No more stiff neck.
--
Jim in NC

Didn't know such things existed. Hang around in this group long
enough and you learn all kinds of stuff.

I'll check into it, thanks.

Corky Scott

"Richard Lamb" wrote in message
...

Amazing how bright that 1/20000 second can be, isn't it.

My learned brother and I were discussing those hoods one day and I axed him
if that is the technology used in the military to prevent eye damage from
laser attacks. IIRC, he told me that a laser could burn out your optic nerve
before the glass wen t dark.

That laser light must be a lot faster than reg'lar light, huh?

Rich S.

In article ,
"Rich S." wrote:

"Richard Lamb" wrote in message
...

Amazing how bright that 1/20000 second can be, isn't it.

My learned brother and I were discussing those hoods one day and I axed him
if that is the technology used in the military to prevent eye damage from
laser attacks. IIRC, he told me that a laser could burn out your optic nerve
before the glass wen t dark.

That laser light must be a lot faster than reg'lar light, huh?

Rich S.



I hope that you didn't injure your brother too much when you axed him!

"Orval Fairbairn" wrote in message
news

I hope that you didn't injure your brother too much when you axed him!

Naw. He's too smart to get hit. PhD's in physics & math, Master's in
languages & economics. Speaks english, rooshian, japanese, german, klingon,
and C plus. Or something like that. Ex-fighter pilot, too. He's my hero.

Rich "The dumb one" S.

"Todd Pattist" wrote in message
...

It's not speed, it's brightness. If you can squeeze enough
energy into the 1/20000 second, you can do the eye damage
before the glass darkens. Lasers can make high energy
femtosecond pulses. Welders can't.

Todd............

Jes' kidding about the speed - but you knew that. )

But - I didn't know what other quality might be responsible for retinal
damage - color, frequency, brightness or penetration of the shield.

Thanks,
Rich

But - I didn't know what other quality might be responsible for retinal
damage - color, frequency, brightness or penetration of the shield.

------------------------------------------------

'Red Eye' -- various complaints of sore eyes -- is a common hazard in any
welding environment. You may not even be aware of it butarc light can enter
your eye at an angle and do plenty of damage to your retina at sites other than
the point of focus. SOP is to block the light at the source -- drape every
welding station with UV barriers -- or keep the people out of the area.

----------------------------------------------------

As for the original thread, I've found vee-blocks, step-drills and a couple of
throw-away angle-head grinders to be handier than any of the tools mentioned,
other than basic hacksaw & files. Being able to maintain the axis of your
notches is more important than a perfect fit.

Real-world practice projects are tables & benches of every size, gate & door
frames, car-top carriers, racks for pipe, lumber and tubing, booms and cranes
for shop lights and electrical extensions, and so on.

-------------------------------------------------

Gas -- oxy-acetylene -- is the best teacher, probably because you can SEE when
you have the chemistry of the flame correct. Beyond that, it's all about the
puddle. Gas is slow, which is good for the novice. You can transfer a
majority of your gas-derived skills to other welding methods, each of which is
valid for airframe fabrication when properly applied.

---------------------------------------------------

A point most novice builders fail to appreciate is that the actual amount of
time spent welding is insignificant in relation to the overall project. It
looms large simply because you don't know how to do it or lack confidence in
your skills. The key to success is the same as for any other manual art, be it
typing or car-quals -- you have to practice. The basic principles can be
mastered in about thirty minutes. You'll then need about twenty hours of
practice to produce welds deemed 'safe for flight' (which doesn't mean they'll
be pretty :-)

-R.S.Hoover

"Veeduber" wrote in message
...
But - I didn't know what other quality might be responsible for retinal
damage - color, frequency, brightness or penetration of the shield.

------------------------------------------------

'Red Eye' -- various complaints of sore eyes -- is a common hazard in any
welding environment. You may not even be aware of it butarc light can
enter
your eye at an angle and do plenty of damage to your retina at sites other
than
the point of focus. SOP is to block the light at the source -- drape
every
welding station with UV barriers -- or keep the people out of the area.

Many's the night I've laid awake from the "sand" in my eyes. I used to keep
a vial of optical anesthetic handy until my stepdad lost a cornea by
ignoring an irritation. It turned out to be a rock chip scratching the lens.
After that, I'd go to the E.R., get the dye in my eye and lettum look me
over with a loupe.

Another danger from the "rays". Back in the thirties, my dad was
moonlighting at a job doing production bench welding. One day he came down
with a penile discharge. He went to the fire department doc, who informed
him he had a STD and demanded to know the name of his "partner". For once in
his life, the old man had been truly faithful and my mom was given a clean
bill of health. The Fire Department threatened to fire him unless he came
clean about his extracurricular activities.

In desperation, dad went to see the public health doctor who examined him
and believed his story. He asked dad what he had been doing lately. Finally
the story came out about the off-shift job. When dad told him he had been
sitting down, welding at a bench, the doc exclaimed, "What Amperage?"

It turned out that the radiation from the arc was causing the problem. Dad
quit the job and the discharge went away. That's his story and he stuck to
it.

Rich

Don't know much about the science of it, but I know that the different types
of laser protective glasses that I've been issued in the military are not
dark at all. They are simple plastic safety glasses with a very light
colored, slightly reflective coating. I assume it employs some sort of
polarizing or refractory principle to disrupt the beam. We never carry
them.

"Rich S." wrote in message
...
"Richard Lamb" wrote in message
...

Amazing how bright that 1/20000 second can be, isn't it.

My learned brother and I were discussing those hoods one day and I axed
him
if that is the technology used in the military to prevent eye damage from
laser attacks. IIRC, he told me that a laser could burn out your optic
nerve
before the glass wen t dark.

That laser light must be a lot faster than reg'lar light, huh?

Rich S.

Actually, none of the automatic lenses on the market today will allow
damage to your eyes even if they do not darken fast enough or properly.
The early auto-darken lenses were virtually transparent to UV until they
darkened. Speed of transition became the code of the day, but the
solution was to tint the un-activated lens and use UV filtering
materials as part of the lens. Today's lens' speed reduces or eliminates
the "dazzle" of the arc strike, but even if the activation section of
the lens is blocked so that it doesn't activate you don't get flash
(sunburn of the retina).

"Rich S." wrote:

"Todd Pattist" wrote in message
...

It's not speed, it's brightness. If you can squeeze enough
energy into the 1/20000 second, you can do the eye damage
before the glass darkens. Lasers can make high energy
femtosecond pulses. Welders can't.

Todd............

Jes' kidding about the speed - but you knew that. )

But - I didn't know what other quality might be responsible for retinal
damage - color, frequency, brightness or penetration of the shield.

Thanks,
Rich

--
Bruce A. Frank, Editor "Ford 3.8/4.2L Engine and V-6 STOL
Homebuilt Aircraft Newsletter"
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| on all aspects of alternative |
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