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maddog
12-08-2004, 08:51 PM
I just got a new Millermatic, it seems like
it welds so much nicer than my old Hobart
from the 1980s.

Are the new machines all that different or
was my old rig just tired out?

TIA.... MD

Elninio
12-08-2004, 09:36 PM
some improvements are made but probably not much, performance also depends on the torch?

Michael Az
12-09-2004, 09:52 AM
The first new welder I bought was a millermatic 185 about 10 years ago. I couldn't ask for more than it has done. Haven't had any problems with it.
Michael

Ries
12-09-2004, 05:58 PM
"Some improvements'?
Dude, your age is showing- pull up those baggy jeans.
I have only been welding for a little over 30 years, and I have seen Amazing improvements in welding technology in that time.
I started off with boat anchor copper transformer machines, that were hard to do anything with.
Now I have inverter power supplies, and the difference is very noticeable.
Not sure about the exact tech in your miller wire feeder, but chances are at the very least it uses electronics for very fast switching to convert the AC wall current into DC welding current, and that makes a big difference.
If you get a chance to try an inverter power supply, the weld bead is cleaner, its easier to weld with, and you can dial in penetration and spatter much better- like the new Miller 351P mig welder- pulsed, programmable, and kick butt.
Inverters and pulsed power supplies also vastly improve tig welding.
And plasma cutters cost over a hundred grand in the 70's.
Technology can be your friend, especially when it comes to welding and cutting.

#66B
12-09-2004, 10:06 PM
The older migs were constant current, all the migs in the last 10 - 15 years are constant voltage, makes a lot of differance.

maddog
12-10-2004, 06:06 PM
That must be it, CV vs. CC.

Speaking of transformer machines, My TIG is
an old Miller 360A, It weighs a ton! I was
wondering if I should upgrade to a square
wave machine. Would the welds look better?

Somtimes my (TIG) welds look like ****.other
times they look great. I'm wondering whats
up with that.

#66B
12-14-2004, 06:10 PM
What are you Tig welding ??? Aluminum, I have a 300 amp Hobart Cyber-Tig ( old ) works fine, but no foot pedal.

torker
12-14-2004, 07:32 PM
maddog...If your machine is kept blown out and clean and if all your hoses/connections are in good shape then your welds should be consistant. I've ran a lot of welders that were dirty but once they were cleaned out they welded better. If it is alu you are having problems with it's usually the present surface oxides that cause most of the problems. Sometimes it can be harder to remove than others. Also beware of oxides on your tig rod. I have a whole box of 1100 rod that is just awful. Have to sand each rod down with emery and then with SS wool before I can get a clean weld on 3003. It's even worse trying to gas weld it unless it's perfectly clean. Also watch your cup contamination and the ball on the end of your tungsten. A small variance in the shape of the ball can make the arc unstable. An unstable arc can "suck" contaminants from a lot further out than you think.
Russ

maddog
12-16-2004, 10:08 AM
<font face="Verdana, Arial" size="2">Originally posted by torker:
maddog...If your machine is kept blown out and clean and if all your hoses/connections are in good shape then your welds should be consistant. I've ran a lot of welders that were dirty but once they were cleaned out they welded better. If it is alu you are having problems with it's usually the present surface oxides that cause most of the problems. Sometimes it can be harder to remove than others. Also beware of oxides on your tig rod. I have a whole box of 1100 rod that is just awful. Have to sand each rod down with emery and then with SS wool before I can get a clean weld on 3003. It's even worse trying to gas weld it unless it's perfectly clean. Also watch your cup contamination and the ball on the end of your tungsten. A small variance in the shape of the ball can make the arc unstable. An unstable arc can "suck" contaminants from a lot further out than you think.
Russ</font>

I'm welding stainless, and cast aluminum.

What do you mean by cleaned out? My torch
and hoses are new and I run city water for
coolant.

You mention "cup contamination", is that
the crap that collects around the edges
of the ceramic? Whats the best way to
clean that crap off without breaking the
cup?

WRT the ball, I usually make it the same
size as the tungsten itself. Is that the
proper way?

I been TIGing for 5 years! I thought
my welds would look better than they do by
now.

On the aluminum; When I apply the rod to
the puddle, I get this green glow in the
arc and it turns the surface black. I'm
assuming this is contamination. I tried
cleaning the rods with laquer thinner,
that helped a lot but it still happens.

#66B
12-16-2004, 09:25 PM
By chance did you run out of argon while welding, I did once & you have to purge the entire system for approx. 20 minutes seems like a great waste of argon but the only way to correct it. Some of the cast aluminum will never give you a good look'in weld.