Pulsing is not the same as the frequency of current. Imagine this
waveform, with high and low amplitude:
that is, some cycles are with low amplitude and some with high
amplitude. The AC period is the width of the letter V, the pulse
period is the length of sequence VVVVVvv.
I've got a Thermal arc 185, A/C, D/C inverter based, TIG / stick .
it has a pulser, sequencer, digital read out.
lift arc, high freq.
gas pre flow, post flow adjust
Stick- hot start adjust
A true advanced squarewave TIG .
I really like it.
it was $1650.
I went the used welder route and am curious. Are used welders more
prone to failure than they were when they were new? As for the
inverter based ones, what is it that can go bad in them besides the
Im looking at the same ones too. Seems like someone said the Miller
were better than the Lncoln but I really dont know. If your like me , a
used one not trashed wld work fine but they are hard to find. Plus,
again , if your like me, just for shop and home use, it wont get used
much and wld prob last forever,.
Im gonna stay intouch with posts on the dynasty. I did see one guy post
that he really liked his. But heck he cld be a salesman too. Go
Good Luck and let us know what you do.
: Im gonna stay intouch with posts on the dynasty. I did see one guy post
: that he really liked his. But heck he cld be a salesman too. Go
--I believe him. Ya see last year Ernie dropped by and brought
*his* Dynasty and showed me how it worked. I sorta swooned and decided
right then and there that I'd have to get one some day... ;-)
"Steamboat Ed" Haas : Nihil curo de ista tua
Hacking the Trailing Edge! : stulta superstitione...
That makes sense... I looked into my Cybertig a little bit... If the
boards fail, I am likely fully screwed. If the power modules like SCRs
fail, I hope that I would be able to replace them. Mine seems to be
built such that it stays well within the safe operating area for the
electronics, so I hope that I will get some life out of it.
Note that the problem of stocking semiconductor spares goes way way beyond
welders. Consider the lifespan of say a Boeing B-52, now in what, they're 40th
year of service? Whenyou think of a product which has decades of service life,
then compare that to the rapid change in semiconductor technology. Say a chip
was designed that went into some board on a large machine in 1978. The
manufacturer would have to had ordered, tested, labeled, and stored enough spare
parts from their initial semiconductor run to last FOREVER. How would you feel
if you went to ask for a little part for your welder and they said they have it,
but it's $2400? How much does it cost to keep parts around?
My point is that chip was designed in technology that is now ancient by modern
standards, it would be as if we had to go back to Bronze Age smelting techniques
to fix a pulley on a sailboat, just ridiculously impractical. It's conceivably
possible to fully specify the function of the chip and then redesign it for
another production run later one if needed, but then you run the terrible risk
of not getting the design quite right.
I own a Tektronix 2445 oscilloscope, for which many parts are no longer
available from Tek. My only solution was to buy and store a complete parts
scope. I have been offered $500 for a single *chip* out of my parts scope!
So yes, you have to figure welders with complex integrated circuitry have a
finite lifespan, but realistically this will be reflected in their value, and so
old broken ones should become available with spares, kind of like if you own a
1930s Packard car.
Well, I do not knw much about B-52 parts, but I heard thet B-52s have
modular construction and a lot of systems undergo upgrades. These
planes are projected to last for decades to come. But I know that the
military stocks up a lot of old parts, I know that by getting them as
Onan still has parts for my 26 year old DJE diesel generator. Not as
much for Onan CCK generators, the older gasoline gensets.
You do have a good point about obsoletion.
Seems like too much, I thought that they are worth a lot less.
I agree. You made some good points. I really like my $9.99 welder and
they seem to be generally available, so I could get spares if
I needed. Mine seems to be built to last (meaning parts operate well
below their rated limits and are of good quality), but like you said,
everything can fail eventually.
Absolutely. I have a behemoth of a welder, as far as relation of size
and weight to output power is concerned. And I like it that way:
1) everything is fully open and if not obvious (to a newbie like me),
at least I can trace what is going on.
2) It is overbuilt, which can hopefully add some years to its life.
My welder was completely covered by filth. It was so bad. It still is
filthy, as some dirt is basically glued to it, but to a lesser
extent now. I spent perhaps 20 min vacuuming it.
50 years of service IIRC.
Biggs AFB got theirs in late 55 or 56. They (3 wings) were in war paint and in
for the little one that never happened. The Recon group flew over and took
before and after the 'problem'.
Dad was the WECO TECH keeping up the Radar.
I think the frames are in Rev D or E now. Been a while.
@ home at Lions' Lair with our computer lionslair at consolidated dot net
NRA LOH, NRA Life
NRA Second Amendment Task Force Charter Founder
Grant Erwin wrote:
You can definitely get the SCR's and the like for it. I've had to
replace mine twice. The first time I didn't have the schematic so I
didn't know someone had switched wires in the machine. The second time
I found the crossed connections and I've not had any problems since.
Actually the SCR's are the easy part. The hard part is the high speed
fuses that protect the SCR's. Those cost me much more than the SCR's
the second time.
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