MIG questions (features?)

found what seems to be a good deal on a 300A MIG welder.
i tried it out last night and have a few questions about settings/options.
1. this machine has 2 ground (quick connects) one marked "Steel" and
one marked "Aluminum" ... the steel socket has an icon of what looks
like 2 loops of a transformer. the aluminum, has 4 loops.
what is the effective difference between these two ground sockets?
2. it has a button for "BackBurn" control. what is Backburn? and why
do i want to control it?
3. this welder has 30 settings. (my current Cebora has 6). one knob
selects "LO/MEDIUM/HIGH" the other goes from 1 to 10. how the
heck do i figure out which is best, since the selections come in such
small steps?
is it ALWAYS supposed to sound like frying bacon, like i was taught?
that being said, i ramped the welder all the way up.. HIGH setting on
first knob, "10" on the second, with wirefeed all the way up. it made
a really highfrequency buzzing sound. kinda like a squarewave machine.
-- didnt sound pleasant, at any rate.
it has no literature so i dont know what the waveform even is. turning
the wirefeed down just made welding impossible at that high setting.
i'd say, when i lifted my torch, the last 4" of puddle were still
molten.
i was running 1mm wire.. the 'bead' was 1/2"wide and 1/4" high, more
or less.
thanks,
-tony
Reply to
tony
Loading thread data ...
I am guessing the aluminium gives a more violent arc to knock off the oxides. Burnback control sets the time between the arc current is off and the feed motor stops feeding wire. If your motor stops too early then the arc burns back up to the contact tip. This can cause a damaged tip or a wire melted inside the tip. Your wire feed controls amperage. With the other control you are adjusting voltage. You can adjust voltage from a frying bacon sound called short circuit transfer ( ~19 volts) to globular transfer (~ 24 volts) to spray transfer ( ~28volts) All these voltages are also dependent on the gas mix you use. Spray is not attainable with more than 20 % CO2. Does the machine have a voltmeter on it? With a 300 amp machine you should be able to indeed see a four inch long cooling bead as you describe. Randy
Reply to
Randy Zimmerman
This is testing my memory, I'll try not to hurt myself. "Normal" welding should sound like bacon (or close). But once you start pumping a ton of power into a weld it'll sound a bit different. If you get enough juice flowing where you begin to do spray transfer (usually done with different gas, and different settings to do it "right", but it can happen with a regular setup run very hot). It'll sound... well... like one heck of a arc... not much like bacon at all. I've only done this a bit in welding school (almost 6 years ago), but man it was fun.
Oddly enough there was one time the welders settings got screwed up (via the instructor, it was to test us). Some how it was set so it sounded absolutley horrible (imagine bacon frying ever few seconds with huge bursts lol). The weld looked awesome, and actually was fairly sound (wouldn't pass the 'cert test, but held the plates together).
The only clue I have about the 2 grounds... is there a place to have 2 stingers/guns? If the welder doesn't have a chart on/in it, and there isn't one in the manual (if there is a manual) basically the only way is trial and error. Eventually you'll get used to it and be tweaking like a pro (while others wonder how the heck you know which setting to use).
I'm no expert by any means, but these are the answers and opinions of the poster, ymmv ;-) -- Lynn "I have opposable thumbs, and I'm not scared to use em" Amick
formatting link

Reply to
Lynn Amick
hey, thanks for the input. Lynn: no the machine doesn't have a spot for a 2nd gun. i have, however, seen alot of the newer machines with two ground lugs/plugs. none of them, beside this one, were marked "steel" and "aluminum" -- but all of them always have the two icons next to the lugs.. a single turn coil, and a double turn coil.
i asked a rep once and he told me (for Cemont machines, anyway) that one was for thinner metal and one was for thicker. dunno how true that is.
maybe once i get up into the 300A range, i need to change out and use the other ground socket??
i bought this machine, by the way.. ended up being a good deal and boy am i having fun with all this juice!
-tony
Reply to
tony

PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.