Ive been offered a complete, though absolutley filthy Miller Dialarc
250 HF welder..stick and tig, Includes the Miller cooler, tig torch,
pedal, leads etc. $200
At this point, I dont know even if it works, but assuming that it
does, is this a machine I want to mess around with? Its older of
course and I have the identical machine in AC/DC stick only which I
rather like, having a very mellow arc, easy to start, etc etc.
Im still hunting around for a cooler for my Lincoln 250 tig/stick
machine and this Miller is the price of a good cooler, with all the
Do I want to go there or pass on it? Assuming it works of course.
"To be civilized is to restrain the ability to commit mayhem.
To be incapable of committing mayhem is not the mark of the civilized,
merely the domesticated." - Trefor Thomas
Oh my goodness, come on you dont have to think about this one, it's a
very good deal. (Sorry for being so informal, I just know u from
lurking). I know you like to fuss around and repair stuff, so the
parts themselves are worth it. Think about what this machine has that
your none HF dialarc has. Porcelain base with aluminum heatsinks with
4 tungsten contact points ($150 Miller pricing, gotta be at least $75
ebay pricing for people looking to build van degraff (sp?) generators).
Complete HF circuitry with high voltage transformer as well as high
voltage capacitor, and really beefy inductance coil (air transformer).
On top of that you get two solenoids (gas and water) with a nice little
standalone circuit board on the gas solenoid to adjust postflow.
You have all the parts necessary to build a standalone HF box. The
only thing that has a decent chance of not working ith the HF will be
the capacitor ($100 miller, I bought a doorknob cap on ebay for $30).
I have fussed with the dialarc, lincoln tig 300/300 and an LTEC (which
I currently have) and without doubt the miller had the beefiest built
HF circuit. ... And then if the welder itself works ...
But you also have the cooler (which I paid $180, $220 to my door, for
on epay and was ecstatic), the footcontrol ($60 epay) and "stuff". You
know you have a good deal. Again, sorry about being so informal, and
note that I am a newbie welder, metalworker, and poster, but I am a
Could you elaborate on "sucky" please? I have been using a Dialarc 250
HF for TIG for quite a while and am pretty happy with it. Mostly I weld
mild and stainless steel with it but recently have been welding aluminum
with OK results. I am wondering what a newer machine would provide that
I am not getting with my Dialarc, and whether it would be worth the
money to upgrade... There is a Synchrowave 250 in the paper here.
TIG welding can be achieved with a HUGE range of machines.
A bare bones DC stick welder, a valve body torch handle and a bottle of
argon, are all you really "need".
In the range of machines from a barebones box to the ultimate TIG, the
Miller Aerowave, there are many levels.
How new or fancy of a TIG you need depends on what you are doing and
If you are doing hobby stuff around you shop and maybe some simple
projects for friends, then you are likely to be willing to put up with
a less than perfect machine if it saves you immediate cash.
So a simple TIG like any of the old Miller Dialarcs, or Lincoln
Idealarcs will be fine, or even a tiny TIG like a Miller Maxstar 140
or 150 inverter.
Maybe one of the smaller AC/DC transformer TIGs such as the Miller
Econotig, yncrowave 180 or a Lincoln Square Wave 175.
If you do mostly aluminum, then you really need a "square wave" AC
capable TIG machine.
This includes all the Miller Syncrowaves, Hobart Cyberwaves and later
Cybertigs, Lincoln Squarewaves and PrecisionTigs, and many others that
date from the late 70's on, including all AC capable inverters.
Sine wave AC machines will work, but not nearly as well, and the high
frequency units on really old machines will often be a major source of
Those old machines make fine stick welders with a really smooth arc,
but they are just not the best machines for production aluminum.
The ultimate AC welding experiences are AC capable inverters, like the
Miller Dynasties, Lincoln Invertecs, Thermal Arc GTSW's and TSW's, HTP
Invertigs, and lots of others.
AC capable Inverters allow you to adjust the actual frequency of the AC
arc from a low of 10hz to a high of 200hz or 500 hz.
Running an AC TIG arc at a higher frequency makes the AC arc act like a
DC arc, so your tungsten lasts much longer, the weld puddle is
incredibly smooth and the arc is quite directional which makes fillet
welds so much easier.
DC TIG hasn't really changed as much as AC TIG so if you aren't doing
much aluminum then you can likely get along with an older or simpler
Once you get past the squarewave AC thing, you get to the world of
pulsers and sequencers.
Do you need either? Maybe not.
Are they really useful? You bet your ass.
Pulsers cycle the arc output amperage from high to low, allowing much
more control on thin materiels and giving a better appearance to any
Sequencers allow the control of a "sequence" of events in the machine
with a simple button tap.
This allows much easier welding in out of position situations where a
foot pedal or even a thumb wheel are not practical.
So if I say a machine is "sucky" it is not asying it won't work.
I am saying compared to even an older Syncrowave it isn't a great TIG
At school we have 6 Syncrowaves of various ages, a Hobart Cybertig 120
from the early 80s, a Lincoln Idealarc 300/300 from the 70's, and a
pair of 2 year old Lincoln Squarewave 175's.
Personally I would like to toss the Cybertig and the Idealarc into the
They do work, but not even close to as nicely as even our oldest
Before we got most of those Syncrowaves from Boeing Surplus we were
cursed with Miller 330AB/P Gold Stars.
Passable DC TIGs if you have no option, but absolutely dreadful on AC.
When they were new in the 70's maybe they were better, but now they are
just too beat up and worn out.
Bad high freq generators and too many really old parts that do wear out
We still have one of them over in a corner set up with a valve body,
flex-head, air-cooled, #3 series torch to be used for scratch start TIG
for pipe welding training.
In the world of used machines, Syncrowaves are the best of the
transformer machines out there.
There is a reason why Miller rules the TIG world.
So, is your Miller Dialarc "good enough" for what you need?
That is up to you.
What I would suggest is find a place where you can test drive a newer
machine, and then you will really see the difference.
On AC TIG, the simple rule stands.
The newer the machine the nicer it welds aluminum.
BTW I still believe the best deal in the TIG market today is the
ThermalArc Prowave 185TSW, AC/DC Inverter, at around $1750 complete.
Thanks, I was wondering if I should start looking at replacing the
Dialarc before my worn out lathe... It sounds like I should try a newer
machine and see how it goes. I do a lot more welding than turning.
On Sat, 25 Dec 2004 01:59:04 GMT, Ernie Leimkuhler
Ernie..is my big Hobart Cybertig 2 500 DCS a square wave machine? Its
got all the ramp up/down yada yada stuff on it.
Its a mid 80s machine as best as I can tell.
So my Lincoln 250 tig/stick is not all that great for aluminum?
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Squarewave vs. Sinewave AC TIG welding, how to tell the difference
Sorry, but I'll butt in to this thread again. I asked the same
question with the machine that I have, an LTEC 306N. I was not sure if
it was a squarewave machine or not. I wanted to know if there was a
way to tell the difference, when welding, if the machine was a
squarewave or sinewave machine. However, no one replied and I could
not find any threads on a google search, so I just started welding on
different machines. I found it is pretty self evident when welding if
the machine is a squarewave or sinewave.
On aluminum an AC sinewave machine will give you a wide shallow bead
(the profile of an M&M) with a very narrow cleaning band, which barely
extends beyond the toes of the bead, if at all. The puddle will not be
as shiny and will often include inclusions in the puddle as you weld
(little black stuff floating on puddle).
On simple AC squarewave machines the bead will still be a wide shallow
bead, however the cleaning band is about twice the width of the bead.
The puddle is noticeably shinier and much cleaner with far less
I found on the squarewave 180SD and the lincoln equivalent which have a
balance pot switch. I could sort of replicate the narrow cleaning band
of the sinewave machine but this was with the balance control set for
more penetration and less cleaning. The bead itself then is very
different it does not look like an M&M but actually has a v-type
profile, sort of looks like a spinning top. Of course the puddle is
very shiny and has no inclusions.
I have also welded on some inverters, dynasty and the like at welding
store previews but did not have enough time to really investigate it.
However, I bet I could replicate the sinewave bead by setting the
balance control to more penetration-less cleaning and then turning down
the frequency to give me a shallow bead. However, this is just a
hunch. Of course the puddle would still be shinier and cleaner.
I guess what I'm saying is that AC sinewave and squarewave machines
have distinct characteristics when welding, which are easy to see.
Thanks for sharing the research.
It bears out my experiences.
BTW on the Lincoln Invertec 205 (really a Selco Genesis 200 from
Europe), they give you 3 choices of wave form for AC TIG.
Square wave, Sine Wave and Triangle wave.
I have yet to see anything written anywhere that shows any benefit to a
sine wave or triangle wave form in AC TIG.
I would like to play with one to figure out what the effects are.
A lot of the European inverters offer these wave form choices.
All TIGs were squarewave by the early 80's, as long as they were
actually TIG machines, and not just stick welders you can TIG with.
It depends on what kind of life it has lead.
Lincoln built tough high freq. units, but they all need to be
A syncrowave will out weld it on AC aluminum, but that has a lot to do
with the arc control and filtering that Miller uses.
Older transformer TIGs really need a happy high freq. generator to deal
well with aluminum.
The manual for your machine should give the instructions on removing,
cleaning, reinstalling and gapping the points.
Replacing the high freq. capacitors doesn't cost much (around $50) and
can breath new life into an old beast.
BTW Inverters don't use spark gap high freq. generators.
They use something called Capacitor discharge high freq.
Think of it as a high speed photo-flash, charging and firing.
Since they are solid state, they aren't affected by dust buildup.
They also tend to cause less RF interference, which is why they are the
only machines you can use near medical or broadcast equipment.
PS The only transformer machine with Capacitor discharge high freq is
the Miller Econotig.
Which is why they still sell it.
The Syncrowave 180, which was meant to replace it, has true high freq
so it can't be used in medical or other electronically sensitive
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