New to welding, usefulness of 90A arc welder?

admin

I just purchased a "Thermal Arc" 90 amp arc welder from my local welding supply store (in Vineland, NJ). It's rated at 90A and 120V, and I've been told it's only supposed to weld up to 1/8th steel.After using the welder for a bit, I've realized that I may need to weld larger steel, ie up to 1/4 inch. I have some large projects, ie a heavy duty trailer hitch and auto trailer (that can hold 5000 lbs). I plan on calling the supplier tomorrow, but I was curious if it's possible to use the 90A welder for 1/4 framing (square tube, etc), and have it reliably hold a 5000 lb vehicle without the framing falling apart while going down the road (I have it being towed by a 35 foot class A motorhome). I've read that generally people would get a larger amperage welder, ie 230V, but I don't have that option because my house is not wired for that - not unless I maybe 'borrow' my clothes dryer outlet (the plug may need to adapt but at least the voltage is approximate) - which would require me to do all my work in the front of my driveway for everyone to see instead of back near my garage (my garage is detached and behind my house).I was hoping that with the right technique, it might be able to use the 90A arc welder with 1/4 inch tubing for structural welds - ie the frame of the trailer holding the 5000lb car. I've read that there are several things to help the process:1) Use multiple passes to get a thicker (more appropriate) weld2) Pre-heat the joints with a hand-held propane torchI'm assuming I have to go with electrode that is rated for my welder and not anything thicker - otherwise I face it likely sticking/fusing to the metal instead of sparking properly. Is the welder perhaps rated for only 1/8 steel because the maximum size electrode is what would safely secure the steel with a single pass?I'm also assuming that the pre-heat is necessary/helpful so the electrode and base metal fuse more deeply - and that the welder I have may not properly penetrate 1/4 inch steel by itself?Any more possibilities?Will the process also be slowed down and I be required to pause more frequently? ie, will things overheat? The inverter itself seems to be rated at a 35% duty cycle, which I'm guessing means that it can run for 3 1/2 minutes out of every 10 before I have to put the electrode/holder down to wait for it to cool down. Does that mean it's the base steel and weld joint that needs cooling, or is the 'duty cycle' about the machine itself from overheating?I know it's a lot more work, and the most recommended strategy is to get a better welder, but would this all theoretically work? Assuming I have enough practice to become proficient in strong welds. And if it works, is there any risk of structural integrity? And would 45 degree mitered joints (with the square tube framing) work better than 90 degree joints?I get the impression that the most power possible from a 120V system is going to be ~90A, and so unless I go with some sort of gas welding setup, I think I'm limited to the welder that I have. I have to get these projects done and have no interest in being sidetracked with an electrical upgrade.Thanks!TomasLast edited by tomas_maly; 09-11-2012 at 11:07 PM.
Reply:I also spent about $40 on electrodes, which somewhat keeps me wanting to stick with arc welders, at least for now. And to keep the process simple until I get the hang of things before I mess with any more complex of a setup.
Reply:Your trying to do too much with too little. It's one of those "learning lessons" many welders go through.Ask your LWS if they will allow you to return the machine and allow you to "trade up" to a machine with more output.Thanks,HoboLincoln SA200's... at least 15 - 20. They come and go. Growing partial to the "Short Hoods" in my old age. Last count on Short Hoods was 13 in possession.
Reply:I agree with Hobo -- You purchased the wrong machine for your projects. Your assumptions are correct that machine will not penetrate 1/4 by itself, pre heating will help but it still doesnt make sense to build a trailer with that machine...You also are going to be scolded for building a trailer with such limited experience. 2.5 tons is a serious amount of weight and you should make sure you know what you are getting into before you embark on that project and practice practice practice...Make an extension cord from your dryer - I have one that is 75' long and made of aluminum wire intended for a 100A service. It is a pain in the @$$ to roll up but it does the job just fine... it only taked 2 minutes to plug it in and 5 mintues to roll it up when you are done...If you want to keep it cheap get a lincoln buzzbox or a miller thunderbolt.Miller Dynasty 300 DXMiller CST280Miller Maxstar 150 STH
Reply:The only issue with getting a 230V welder that I see is that it SEVERELY limits where I can use it. Many of my projects will be light weight ($600), which I can't afford right now. I have a school bus I'm converting into a motorhome and so I may be off-grid most of the time and so the generator-welders really catch my interest. If something could fit on my back bumper (with proper structural support since they're heavy anyway), then I could carry it as I go and use it whenever I need to. My main concerns is that I'm restricted to about 24 inches across from the side of the bus to the back door. I'm guessing the generator would fit sideways (lengthwise) and am hoping I can find something that small.
Reply:Look at the old Miller AED, AEAD's, Bluestars, Lincoln Weldanpowers, etc. There are also some nice Honda powered small stick machines out there. 1/4" -3/8" is about what the max on many of those small units will do easily. Most of these were designed around small fence and door installers who don't need a lot of power, but need a portable machine that can weld at least 1/4".The more powerful machines are usually too big for what you are thinking about..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:So far I have seen some kits that adapt to an existing small engine, ie an alternator + welder unit. I have a Kohler 13HP engine from a John Deere ride-on mower, and am curious if there are any common kits that I can adapt to an existing generator, that will handle the 200A (I'm assuming) for the thicker 1/4" welding?Or maybe it's just more realistic (and affordable) to find a full older generator+welder. I don't mind fixing a broken one as long as the issue is mechanical (ie the engine, blown head gasket, etc) - assuming the price is right.My only real constraint is the size of the unit - it has to be at most 24 inches on the longest side - otherwise it won't fit where I have room. I have plenty of vertical space, maybe 24-36 inches. Which may mean that I may have to go with the DIY alternator/welder adapter kit?Last edited by tomas_maly; 09-12-2012 at 08:59 AM.
Reply:Here's what I would do, keep the 90 amp welder and use it on your smaller projects. Take the heavy structural work to a pro who has the right machine and the skills for safety critical work.If you want a generator/welder combination watch Craigslist and try to find a Lincoln powerarc4000 or a Miller Bluestar 185. To mount it on your bus go to a heavy truck wrecking yard and find some fuel tank mounts. Mount it on the side under the body using the fuel tank mounts bolted to the side of the frame. Mounting it on the rear exposes it to being damaged or squashed if you drive through a dip in the road and hang up the rear of the bus.Millermatic 185, Lincoln AC/DC 225, Victor torch set, Hypertherm Powermax30 XP, Chicago Electric 90 amp flux core welder, Milwaukee Chopsaw, Wilton Drillpress, lots of hand tools and a nice small shop with a 4' X 8' welding table.
Reply:My advice. Build the trailer. Tack weld it how you want it to be. And have a professional finish weld it. Go all the prep work and have it ready to go so they come in and weld. And not spend time grinding. They roll be in and out faster. And cheaper that way. Then you can practice welding on it by adding the brackets for lights, lisence plate, spate tire, racks for ramps, ect. You will gain plenty if knowledge and skill, and not risk a weld breaking in two and killIng someone.Offering CNC Plasma cutting and welding projects.Follow me on facebook https://www.facebook.com/nobigdeal.fabSupport those that support WW.
Reply:Hi,http://www.zena.net/htdocs/Map.shtml#TopJeff
Reply:The generator/welder being put under the bus via a fuel tank mount sounds like a better idea. Realistically I have about 18 inches of room before it sticks below the side wall, I'm not sure if something that short exists.... What's the easiest/best way to get it up and mounted? Would that be possible with a 2 ton car jack, assuming I can get it somehow onto the jack? Or is there an easier/better way without needing a forklift?Also, has anyone had luck with the alternator-welder kits that attach to an existing truck engine (onto the v-belt)? The downside of that with a 5.9L Cummins engine it might not be terribly fuel efficient.Last edited by tomas_maly; 09-12-2012 at 01:04 PM.
Reply:You're not listening to any of the advice anyone has given you and are still trying to take a shortcut that just aint going to happen. You're in over your head thinking you're going to pick up a 90A welder and do all of this heavy duty structural welding with ease. The money you would spend to put a big enough alternator on a cummins would cost ya as much as the correct welder to just start with. However, you are still going to be the limiting factor in this since you don't know sh!t (I would presume from your posts) from Shinola in the way of welding. Not trying to come off as a d*ck, just telling you how it is. Nobigdeal has about the best solution, but if you can't afford a decent welder, how are you going to afford the material for all of these projects?
Reply:Honestly the hostility is unwarranted and I'd appreciate anyone who can't stand my questions or curiosity in how practical DIY options are to either keep it briefly and politely or not answer at all. I'm very much taking to heart what people are saying, even if I don't say it explicitly. I'm also a forward thinker, and I ask questions about projects that are possibly years down the line. Doesn't mean I'm getting into it overnight, just getting an idea as to what's possible/practical. Nobody really has answered one way or another about the alternator welder kits, and I was curious. Just curious. Questions, that's all they are. I'm not actually going out and doing anything any time soon. I can't learn until I ask questions. Maybe I have a degree in Electrical and Mechanical Engineering, so don't judge my question about using an alternator generator. I probably would build one myself using a smaller separate engine anyway. Why would I want to use a 160HP diesel engine for generating electricity, when I could just as easily use a 13HP engine that seems to be more common in these generator welders? Maybe I asked the question without really thinking it through. Maybe a pre-built one is good enough, light weight, inexpensive (used) and will fit under my bus fairly easily. I never know until I ask.If I want to reinvent the wheel, that's kinda up to me. I'm also a very practical person and so I'd find pretty quickly if the DIY route is not very cost effective. Responding with hostility and ridiculous assumptions is a waste of your time and mine. And perhaps I'm frugal. Save money where I can and spend it where I need to. Maybe it's easier to just get a small used generator/welder, I dunno. That's why I'm asking questions.Whether I come off as a 'stubborn' person is not for anyone to judge, IMO. My lifestyle is my own and I am here honestly to get questions answered, not to be judged or shown hostility.Thanks for those who are answering me politely and helpfully!Last edited by tomas_maly; 09-12-2012 at 02:57 PM.
Reply:Originally Posted by tomas_maly... Responding with hostility and ridiculous assumptions is...
Reply:I'm not necessarily questioning (doubting) people's experience, just trying to work with the constraints I have and see what's involved with various routes. My exposure so far to generator-welders is that they are bulky and won't fit in a 24" x 18" (x whatever) space. Perhaps it may be easier to just fit a stand-alone generator (that can crank enough amps/volts) under there for a 230V welder that I just plug in.
Reply:Originally Posted by tomas_malyHonestly the hostility is unwarranted and I'd appreciate anyone who can't stand my questions or curiosity in how practical DIY options are to either keep it briefly and politely or not answer at all. I'm very much taking to heart what people are saying, even if I don't say it explicitly. I'm also a forward thinker, and I ask questions about projects that are possibly years down the line. Doesn't mean I'm getting into it overnight, just getting an idea as to what's possible/practical. Nobody really has answered one way or another about the alternator welder kits, and I was curious. Just curious. Questions, that's all they are. I'm not actually going out and doing anything any time soon. I can't learn until I ask questions. Maybe I have a degree in Electrical and Mechanical Engineering, so don't judge my question about using an alternator generator. I probably would build one myself using a smaller separate engine anyway. Why would I want to use a 160HP diesel engine for generating electricity, when I could just as easily use a 13HP engine that seems to be more common in these generator welders? Maybe I asked the question without really thinking it through. Maybe a pre-built one is good enough, light weight, inexpensive (used) and will fit under my bus fairly easily. I never know until I ask.If I want to reinvent the wheel, that's kinda up to me. I'm also a very practical person and so I'd find pretty quickly if the DIY route is not very cost effective. Responding with hostility and ridiculous assumptions is a waste of your time and mine. And perhaps I'm frugal. Save money where I can and spend it where I need to. Maybe it's easier to just get a small used generator/welder, I dunno. That's why I'm asking questions.Whether I come off as a 'stubborn' person is not for anyone to judge, IMO. My lifestyle is my own and I am here honestly to get questions answered, not to be judged or shown hostility.Thanks for those who are answering me politely and helpfully!
Reply:Maybe I have a degree in Aeronautical and Astronautical Engineering but I also know how to apply my knowledge. Just because you have a degree doesn't mean you can apply it to real world problems. A ME or EE would have the background knowledge on what it would take to build such a device. Sure it can be built, but I'm trying to be practical here in saying that the best thing to do now is get a bigger welder. That way there is room to grow. You are limiting yourself with 90A. I absolutely agree that it would be better to use the 13hp to use for a welder. However unless you have the working knowledge to fabricate all parts involved (mounts, pulley, way to control the amperage, etc) you are going to spend more money in the long run. There are alternators out there that will work to use as welders, but YOU will need to do the research for yourself to see what will fit your needs. There are a few off the shelf welders that will do what you want, but by limiting budget,space, voltage input, you are limiting yourself from the get go. Sit down and evaluate exactly what it is you need with a little extra built in. Maximize your dollar and space. The inverters of today are much smaller and more efficient than any transformer machine, however they also demand a lot of $$. Whereas you can get a lot of amps for not a lot of money with a transformer but they are big and bulky.
Reply:Tomas..I have read your post in the Mod's forum..I read all the posts here.One thing you must realize is that we as a group here know right from wrong when it comes to welding and as much as I appreciate your willingness to get down and dirty we as a group can and will tell you flat out what you can and can't do with only 90 amps....and it 'aint much..Take the advise with a grain of salt and try to understand we are just trying to help you avoid almost definate FAILURE with your project..And failure here is not an option..We can be very abrasive on the outside but on the inside we are REALLY just trying to help steer you in the right direction.....zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.Originally Posted by tomas_malyHonestly the hostility is unwarranted and I'd appreciate anyone who can't stand my questions or curiosity in how practical DIY options are to either keep it briefly and politely or not answer at all. I'm very much taking to heart what people are saying, even if I don't say it explicitly. I'm also a forward thinker, and I ask questions about projects that are possibly years down the line. Doesn't mean I'm getting into it overnight, just getting an idea as to what's possible/practical. Nobody really has answered one way or another about the alternator welder kits, and I was curious. Just curious. Questions, that's all they are. I'm not actually going out and doing anything any time soon. I can't learn until I ask questions. Maybe I have a degree in Electrical and Mechanical Engineering, so don't judge my question about using an alternator generator. I probably would build one myself using a smaller separate engine anyway. Why would I want to use a 160HP diesel engine for generating electricity, when I could just as easily use a 13HP engine that seems to be more common in these generator welders? Maybe I asked the question without really thinking it through. Maybe a pre-built one is good enough, light weight, inexpensive (used) and will fit under my bus fairly easily. I never know until I ask.If I want to reinvent the wheel, that's kinda up to me. I'm also a very practical person and so I'd find pretty quickly if the DIY route is not very cost effective. Responding with hostility and ridiculous assumptions is a waste of your time and mine. And perhaps I'm frugal. Save money where I can and spend it where I need to. Maybe it's easier to just get a small used generator/welder, I dunno. That's why I'm asking questions.Whether I come off as a 'stubborn' person is not for anyone to judge, IMO. My lifestyle is my own and I am here honestly to get questions answered, not to be judged or shown hostility.Thanks for those who are answering me politely and helpfully!