flame

Steve Ackman writes:

Back decades ago when I had an AC buzzbox (arc
welder), I had an accessory known as a carbon arc
torch; basically a hand-held fixture for holding a
copper-covered carbon electrode a fixed distance from
a ground electrode.

How much did they each cost? Where did you get them?

I ran across it today. Main problem is that it really
is designed for AC, and the arc tends to walk around
the gap more with DC.

I'm a little confused. Why were you running it on DC current and
how did you arrange for the current to be DC? Later on, you say
you don't have the AC welder any more, so maybe it has something
to do with the way it is used with the welder. Are you saying that:
(1) the hand torch runs on DC;
(2) it works ok on DC provided by the the AC welder;
(3) it doesn't work ok on DC you provided by some other means?

That said, I did manage to melt some glass with it.

Neat!

1/4" electrodes; machine set at 30 amps.

implications for house wiring... and higher for better conditions,
as you describe later.

In order to get a stable arc,

To compensate for effects of using DC current?

I had to go with something less than
1/4" gap. It was really too much of a pinpoint heat
source at that setting, so the glass bubbled/boiled.
All other considerations aside, you'd need more current
across a wider gap to get a "softer" arc with more heat
so you could work the glass farther out.
What amazed me was that the rod (standard COE 104)
didn't crackle and spit as it tends to do when you heat
it too aggressively.

The arc is an electric discharge, rather than just a source of heat.
Do you think that maybe the electromagnetic field of the discharge
exerts some control over the molten glass?

From what I saw today, I'd have to say that with the
right setup and a little while dialing in, it certainly
would be possible to do some beadmaking and light
glassblowing with a carbon arc.

Thanks very much for checking this out.
--
Ignorantly,
Allan Adler
* Disclaimer: I am a guest and *not* a member of the MIT CSAIL. My actions and
* comments do not reflect in any way on MIT. Also, I am nowhere near Boston.

In , on 18 Sep 2006 08:13:39 -0400,
Allan Adler wrote:
Steve Ackman writes:

Back decades ago when I had an AC buzzbox (arc
welder), I had an accessory known as a carbon arc
torch; basically a hand-held fixture for holding a
copper-covered carbon electrode a fixed distance from
a ground electrode.

How much did they each cost? Where did you get them?

The welder was from Montgomery Wards. Seems like
it was about $225. The carbon arc attachment... I
really have no idea. Maybe someplace like JC Whitney...
for like $25.

I ran across it today. Main problem is that it really
is designed for AC, and the arc tends to walk around
the gap more with DC.

I'm a little confused. Why were you running it on DC current and
how did you arrange for the current to be DC? Later on, you say
you don't have the AC welder any more, so maybe it has something
to do with the way it is used with the welder. Are you saying that:
(1) the hand torch runs on DC;

This "torch" is really just a fixture that holds
the electrodes. Has leads you attach to the welder.
They don't seem to be as common today as they were,
oh 25 years ago, but they're really simple to cobble
together. Google is your friend.

(2) it works ok on DC provided by the the AC welder;
(3) it doesn't work ok on DC you provided by some other means?

Normally the sub-$1000 welders put out AC or DC; not
both. When I bought the carbon arc torch, I had an AC
welder. That went away many years ago, and the welder
I have now (which does stick welding, plasma cutting,
and TIG welding) is DC only.

That said, I did manage to melt some glass with it.

Neat!

1/4" electrodes; machine set at 30 amps.

implications for house wiring... and higher for better conditions,
as you describe later.

Welders used to use honking big transformers to
convert 240 VAC to something in the neighborhood of
~30 VAC or so (and for DC, add a big ol' heat sinked
rectifier). As your voltage decreases by a factor
of about 8, your amperage increases by about a factor
of about 7 (due to heat losses, etc), so a 30 amp 240V
circuit would get you up to about 210 amps at the
electrode.

Having an arc current of 30 amps, means something
like 4 amps on the house wiring. Kicking the arc up
to 100 amps would mean maybe 13 amps on your 240V
circuit.

In order to get a stable arc,

To compensate for effects of using DC current?

No, to compensate for the fact that I was just
playing around, and had the welder set for 30 amps.

I had to go with something less than
1/4" gap. It was really too much of a pinpoint heat
source at that setting, so the glass bubbled/boiled.
All other considerations aside, you'd need more current
across a wider gap to get a "softer" arc with more heat
so you could work the glass farther out.
What amazed me was that the rod (standard COE 104)
didn't crackle and spit as it tends to do when you heat
it too aggressively.

The arc is an electric discharge, rather than just a source of heat.
Do you think that maybe the electromagnetic field of the discharge
exerts some control over the molten glass?

Nope. Then again, I only played for 5 minutes or so,
and only at 30 amps. I believe MF said that at higher
temps, glass does exhibit some sort of EM reaction.

From what I saw today, I'd have to say that with the
right setup and a little while dialing in, it certainly
would be possible to do some beadmaking and light
glassblowing with a carbon arc.

Thanks very much for checking this out.

Only way I'm going to know is to do. ;-)

Moonraker wrote:
"glassman" wrote in message
...

and you thought I was testy?


Nah. I just have a low tolerance for ignorance.


Then how do you live with yourself?

Allan Adler wrote:

Is Moonraker the local judgemental heckler for rec.crafts.glass

You should be ashamed of yourself for talking about my retarded little
brother like that. He can't help it.

"Kalera" wrote in message
. ..


Allan Adler wrote:

Is Moonraker the local judgemental heckler for rec.crafts.glass

You should be ashamed of yourself for talking about my retarded little
brother like that. He can't help it.

Hey, you nitwit no-talent beadmaker! Where has your skanky self been?

Speaking of retarded......

http://sinmonkey.com/files/sinmonkey%20injun.jpg

Did you miss me, baby brother?

Moonraker wrote:
"Kalera" wrote in message
. ..

Allan Adler wrote:

Is Moonraker the local judgemental heckler for rec.crafts.glass
You should be ashamed of yourself for talking about my retarded little
brother like that. He can't help it.

Hey, you nitwit no-talent beadmaker! Where has your skanky self been?

Speaking of retarded......

http://sinmonkey.com/files/sinmonkey%20injun.jpg

Like I'd miss a bad rash. What's the matter, got PMS again and come around
looking for a fight?

"Kalera" wrote in message
. ..
Did you miss me, baby brother?

Moonraker wrote:
"Kalera" wrote in message
. ..

Allan Adler wrote:

Is Moonraker the local judgemental heckler for rec.crafts.glass
You should be ashamed of yourself for talking about my retarded little
brother like that. He can't help it.

Hey, you nitwit no-talent beadmaker! Where has your skanky self been?

Speaking of retarded......

http://sinmonkey.com/files/sinmonkey%20injun.jpg

Moonraker wrote:
Like I'd miss a bad rash. What's the matter, got PMS again and come around
looking for a fight?


Every day, just like you, sweetheart.

Just my 2 cents, I've seen Kalera's work, and only heard your mouth moonie!

As for the pic, looks close, and honestly, I wouldn;t throw her out of bed
for eating crackers!



Please call me crackers!!! LOL


Jim Redden
J.Redden Design



Beadgasms for all!
"Kalera" wrote in message
. ..


Allan Adler wrote:

Is Moonraker the local judgemental heckler for rec.crafts.glass

You should be ashamed of yourself for talking about my retarded little
brother like that. He can't help it.

LOL thanks Jim!

jim redden wrote:
Just my 2 cents, I've seen Kalera's work, and only heard your mouth moonie!

As for the pic, looks close, and honestly, I wouldn;t throw her out of bed
for eating crackers!



Please call me crackers!!! LOL


Jim Redden
J.Redden Design



Beadgasms for all!
"Kalera" wrote in message
. ..

Allan Adler wrote:

Is Moonraker the local judgemental heckler for rec.crafts.glass
You should be ashamed of yourself for talking about my retarded little
brother like that. He can't help it.