New to welding: Which stick welder to build?

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Hello,  I posted a similar message to this over at CNCZone, but I figured this forum might be more relevant.  I've always wanted to get into welding, and was enthused to learn that you can make a basic stick welder with old microwave oven transformers (MOTs).  I have a long list of projects that need bits of metal stuck together (a custom fence, furniture, boxes, etc).  I'm sure you all know about the various plans out there; it's possible to make a small, basic AC stick welder with 2 MOTs, all the way up to an 8-MOT 220V DC stick welder with PWM power control.  I'm fairly confident that I could build any of them, but I'm wondering if you all think it's better to build something quickly and conveniently (say, a 4-MOT welder running off residential 120V) to gain experience as fast as possible, or try to build The Last Stick Welder I Will Ever Need (8-MOT, 220V).  As a corollary, is it worth it to build in DC rectification to a small stick welder?  Thanks!
Reply:I have found the easiest way is to go to your LWS and buy a welder.. = )  But really, this does sound pretty cool.  I'm not sure I'd be comfortable building one, but I'd love to see some pics and plans for one....  Sounds kind of interesting..Esab TradeMaster TorchSmith AW1A Airline TorchLincoln AC/DC 225/125Millermatic 252 w/ Spoolmatic 15aThermal Arc 190 GTSSpeedGlas 9100v
Reply:always go for bigger unless there  are reasons not to.  you can buy a nice used  a/c tombstone welder for less than  i guess you'll spend.in this case the only consideration is how much power do you have in the wall to run the last stick welder you will ever need?you dont need dc for stick  but it is a good idea while you are designing it.
Reply:I could buy a welder, but the idea of making a decent one out of trash is a pretty cool idea to me.  Here are the main resources I found:A basic welder using 2 MOTsA more sophisticated and larger welder using 8 MOTsAn old thread documenting an AC to DC conversion using big surplus SCRs
Reply:I've seen older transformer AC stick machines go for free to say $100 on CL or at yard sales. I picked up my 1st welder an old AC Craftsman for less than $50 at a yardsale, ready to go. I got a sweet deal on an AC/DC Miller Thunderbolt almost new for even less. You just have to be patient and keep your eyes open. Older Craftsmans, Century's, Lincoln's etc. show up on a fairly regular basis, usually looking like he11 but still working fine since there is nothing that really goes wrong in them.Take note that stick is great for many things, but it has some limitations especially for guys starting out learning. Sheetmetal and thin steel is a PITA to learn on a stick machine. Most sticks work best on steel 3/16" and thicker. If your projects are all thin steel to medium thickness, you are usually best off with a good mig rather than stick..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:If you -want- to build a welder, then sure you can build one.But it's usually easier to just go buy one and then use the welder to build things with. Let's see:- scrounge a bunch of MOTs, hopefully try and -match- them for purposes of keeping the internals consistent;- rewire all the MOTs;- rig up switches and cooling;- add desired capacitance and inductance into the circuit for nice arc characteristics;- add in rectifier circuit using BIG -MATCHED- diodes, including heatsink for diode/rectifier block and cooling;- make/scrounge/adapt a mounting board for all this;- make/scrounge/adapt a cover for all this.Yes it is all certainly possible.  After all those -other- folks made arc aka stick aka SMAW welders using MOTs.  Then again, on the cheap you can just run two or three big 12V batteries in series and maybe add in a coiled hunk of welding cable for some inductance and then stick weld with that.But buying a welder is usually easier and most of the time gives better welding control.  The best laid schemes ... Gang oft agley ...
Reply:Some people like the challenge of rolling their own. You’ll spend weeks collecting all the hardware, tuning, correcting, and learning to weld. Trouble shooting; is it me or the welder? 100 bucks and you’re welding.
Reply:Interesting idea, for someone who already knows how to weld and already has welding machines and just wants the challenge of making thier machine.  That person can easily tell if he made something good or not when its done.  For someone who doesn't know how to weld, you wouldn't have a clue if you made something usable or not cause you don't know what its SUPPOSED to weld like to begin with.My advice-  buy a welder.  After a few years of welding under  your belt, if you still have the desire to make your own welder, build it and let us know how it works!MM350P/Python/Q300MM175/Q300DialarcHFHTP MIG200PowCon300SMHypertherm380ThermalArc185Purox oaF350CrewCab4x4LoadNGo utilitybedBobcat250XMT304/Optima/SpoolmaticSuitcase12RC/Q300Suitcase8RC/Q400Passport/Q300Smith op
Reply:DR makes a very good point.  You really should learn to weld first...Esab TradeMaster TorchSmith AW1A Airline TorchLincoln AC/DC 225/125Millermatic 252 w/ Spoolmatic 15aThermal Arc 190 GTSSpeedGlas 9100v
Reply:I figure I'd chime in here, as I have actually built a MOT welder and am in the process of learning how to weld.  If you go to http://aaawelder.com/70amp.html and scroll down about 3/4 way, the guy who runs the site posted some pictures of the one I built.  The MOT will make an arc for a bit and you might be able to get a bead going, but it's going to stick a lot and blow a bunch of breakers in the process.  The welder itself might be capable of good welding, but considering how much technique there is to learn in stick, it's not a great place to start.I'm currently learning to weld at Comm College, and let me say, using a beefy Lincoln is like knife-through-butter compared to the MOT.  After 14 weeks of burning rod with help and guidance, I actually went back and plugged in the MOT just to see what it was like.  I was able to do a little better, but it's still a pain and I don't think I'll ever make as good a bead with it as with a real welder.On a final note, do I regret building the MOT knowing now that it's not very useful?  Not in the slightest.  It was fun and interesting to do and I learned a lot about how welders work.  I have no doubt it motivated me to find a class and start looking at welders in the store.  So I say this, build it, but understand its limitations, and if you end up still thinking welding is pretty cool, go out and learn to do it for real.
Reply:I'm with zer0vector. I didn't get as fancy, I just made a twin carbon arc torch and a water resistor to keep the ciruit breaker from tripping. I don't regret making it. It was fun, but with out knowing how to use it first it was pointless. But it did motivate me to take welding classes which has been one of the best choices I've made in my life. I still have the torch I built, and use it ocassional hooked up to my welder for small heating jobs.
Reply:Hi I Built a mot arc welder  like the ones on the  instructables web site and had a good experience with it.I stuck it in a old ryobi sander case i had added a cooling fan and a pot dial from a treadmill to regulate the voltage. it was limited in power being  built from only 2 transformers it would burn 1/16 to 1/ 8 rod quite well.my cost was about $25 I bought some heavy gauge jumper cable and used it for the leadsand ground everything else was scrounged. If you build the 6 mot with the rectifier it would be the only arc welder you would ever need.it got me interested in welding and i  bought a 220v arc welderi needed the wire nuts one time and some of the jumper wire on another occasion andthe mot welder is goneGood luck JRLast edited by romancandle; 12-01-2009 at 07:36 PM.Reason: update
Reply:Interesting!The aaawelder page brings up a good point-- Power factor correction might be quite important to the quality of the result.It's probably time to start simulating the welder in something like PSPICE or LTSpice.
Reply:My son and I built a microwave oven welder. I posted about it on the board. I got curious after I saw the one Llamafur did. It was interesting to do and it worked...but only as good as a 70 amp arc welder can work. In other words it wasn't practical for much that we were doing. Hard to keep an arc going, rod got stuck a lot and on and on. If you can build one that operates off 230 volts do that and it might be worth it otherwise I agree with the others that just buying one is the best bet. If money is a problem go to the Chinese Tool Store.
Reply:Originally Posted by eubarchInteresting!The aaawelder page brings up a good point-- Power factor correction might be quite important to the quality of the result.It's probably time to start simulating the welder in something like PSPICE or LTSpice.
Reply:Originally Posted by eubarchI could buy a welder, but the idea of making a decent one out...

An old thread documenting an AC to DC conversion using big surplus SCRs[/LIST]
Reply:Why not just go with a few 12v batteries first get the rest of the stuff from harbor frieght....keep the batteries on a tender...
Reply:I have to admit, part of me thinks this is like 'New to Rock Climbing, How Do I Weave My Rope?' but another part of me thinks: that's some pretty hard-core DIY.Jack OlsenMy garage website
Reply:Originally Posted by DSWI. Most sticks work best on steel 3/16" and thicker. If your projects are all thin steel to medium thickness, you are usually best off with a good mig rather than stick.
Reply:if  your  time is  worth  aneything  get a cheap  220  volt  welder. thair alot   of welders     for  less  than  $200.  new  with  leads ground clamp and  stinger.you  can  spind  $50.00   on  leads stinger  and  a good  ground  clamp .i  am  just and  old  welderwith  over  40 years with  my  head  in  a  hood  .  just  price  everthing .best of  luck
Reply:Hmmm..one man's junk is another man's treasure. Maybe one man's hobby is another man's PITA? I'd say the guy has had some good advice from this forum and if he wants to continue with building a welder out of what (I would call) junk, more power to him! Personally, I would buy a cheap, good working welder, learn how to weld and THEN (maybe) try building one of my own just for the fun of it (or not!). I would like to hear what he decides and how it all turns out if he does try to build one, though.Last edited by dondlhmn; 12-17-2009 at 02:09 PM.Reason: spelling correction