Inveterate diy'er that I am, I've decided to make my own cooler for the 185amp AC/DC inverter tig that I just purchased. After a few days on the welding forums I find that expertise and enthusiasm is somewhat lacking. While trying to get more info on the relative merits of single-pass heater cores and continuous loop radiators, I discover your site. Turns out there is some really impressive accumulated knowledge here. May I beg a few questions? The tig torch/cable/hose setup I'm ordering recommends 50psi at around one gpm. Bigger welding machines require more gpm, but mine is considered "light" welding. At these flow rates, what would be the optimal radiator? As an exercise, I'd like to try to make it as lightweight and compact as possible - ideally 7"W x 7"T x 16"D. The welder itself is only 40lbs and the size of a large briefcase with a 7 x 16 footprint. I'd like to attach the cooler permanently to the bottom and still be able to carry it around easily. The motor/pump used in the commercial coolers is usually a 1/3hp industrial job with a ProCon Series 1 bronze pump. Real heavyweights. I imagine you guys have much better ideas about what would fulfill requirements for performance/dependabilty in a lighter package than this. I'm trying to find the perfect sized one gallon red poly gas can for the reservoir. In the interest of saving space, I'm hoping to use a centrifugal impeller type fan (similar to the little one you find in many hand tools) rather than a more typical axial-flow fan. This would enable me to place the motor only the blade-width away from the radiator and exhaust radially away from the cooler's sides. The pump would be driven from the rear shaft of the motor. I cannot find much info on this style of fan blade - or what the rpm/performance characteristics are. Anyone know a source? I'd also like an audible alarm for flow +/- set limits - flow failure would lead pretty quickly to some real expensive damage (I'm sure y'all can relate). Any ideas how this can be done reasonably? The flow switches I've seen online are hundreds of dollars! And lastly (thanks so much for listening), Seems like a glycol based blue windshield washer fluid would be an ideally cheap, algae preventive, and non freezing coolant. No? Forgive me if many of my questions might have been answered by a more thorough search of your threads. I just don't know enough yet about what to look for, so I just dove into a first post. Thanks very much for any advise you can give to a non-overclocker! (four year old toshiba laptop)
Can I clarify: 1) you are wanting a built in compressor for the plasma air (consisting of the centrifugal fan) 2) you are also wanting a liquid cooling setup (to cool the tranformer..?) with the ProCon thing and the radiator? flow can be checked with pressure - too high and there is a blcokage, too low and there is a leak. check just after the pump. centrifugal fans are pretty good with higher pressures/flow rates. Surely it shouldn't need to be water cooled, as the duty cycle it is designed for should allow it to operate continuously at some setting...or is it being taken to the limit? Continuous forced air cooling is usually enough, as the heat never builds up with a decent setup. [EDIT] reading this post this morning i discover I have made a stupid mistake. The air inlet for the TIG needs to be an inert gas! NOT juts pressurised air ! Thsi can only be done out of an (expensive) bottle. I had it in my head that you meant plasma cutting for some reason... actually if you have a mate in the pub business, they could supply you with cheap pub gas (CO2) [/EDIT]
hey I thought I would chime in, I happen to work as a Tig welder full time and I've watercooled plenty of systems but I've never heard of anyone doing a homemade water cooled torch. I assume you already have a watercooled torch, and it seems you've done your research in terms of flow, pressure etc. The next place to go from there is maybe research the add-on watercooling systems just to get a rough idea of types of pumps and fans they are using. I'd also try and figure out what you can get away with, just because your machine is rated at 185 amps doesn't mean you'll be welding that hot for extended periods of time, also depends on your duty cycle. I don't know about you but even when I'm going full blast my duty cycle is probably around 50/50. If you're doing light work, tacking etc you might be able to get away with something less. In terms of actual construction I would be lost. 50psi and 1gpm flow is a much higher PSI than the low flow/low pressure systems you'll find in computer watercooling, it's also reflected in the fittings etc. IIRC they are removing a fair deal more heat which might lend to the fact that the add-on systems i've seen and used are a decent size and have more than a 1gal reseviour., which by the way is probably the cheapest way to improve any watercooling loop, just add more water. at any rate I wish I could be more help on the specific contruction but you are going into fairly uncharted waters. coolant wise the types of additives we normally use water wetter, purple ice etc should be sufficient, as they are meant to not break down, improve cooling and most are anti-bacterial, these are also glycol based solutions, but windshield wiper fluids are meant for cleaning not for cooling, and water wetter etc are about the same price and can be found at hardware stores. flow switches are not my realm of expertise but they shouldn't be that expensive. at that price you could buy a flow meter and just see what the flow was, again I wish I had more help but if I was designing it for my cheap self I would get what ever switch had some preset value in the range I wanted, or I would hack some other way to detect another result of blockage, such as return water temp.
Metarinka, Thanks so much for that. I don't have as nearly as much tig experience as you. I learned on a miller sync 250 in a machine shop that I worked in for two years. Then I took a tig class at community college to round out my knowledge. I've always wanted a decent little project machine, so when this one went on sale I bit. I've always had access to water cooled and gas cooled torches, and have just gotten spoiled I guess. Even at lower amperages, the gas cooled torch can get distractingly warm, and the cable is much less flexible. Water cooled just adds a level of comfort and control that I appreciate. I can get a very good 12ft torch with a flex head for 75 dollars here http://www.welding-direct.com/sr250ampflex.html ...and I'm looking at less than 100 dollars to build my cooler. That's a really attractive budget for upgrading to water cooling. For the pump, I'm simply going to go ahead and buy the industry standard Procon vane pump that's used in most tig coolers with a 50psi bypass. Rebuilt is cheap off ebay. I just wish I could get more definitive answers to the matter of continuous coil vs single/double pass radiators for these flow rates, pressures, and heat. I've asked everywhere. I even got a response back from an engineer at a radiator manufacturer who confirmed unequivocally that the single/double pass was superior for my use. Then somebody on a weldiing forum told me otherwise and even posted pics of the inside of his 600 dollar name brand tig cooler and right there bolted inside was a condenser style continuous coil radiator! I'm agonizing over this so much because I can purchase both styles to fit my project dimensions, and am adamant about making this thing very small and lightweight so that I can bolt it right to the bottom of my 38lb suitcase sized inverter tig. Do you know of anyone in your line of work that would know more specifically about this?
yah I was spoiled too, I learned on top end models like the syncrowave 350 when I got my degree in welding. and I've always used watercooled torches but back in my schooling days our duty cycle was nearly continous and we'd burn up lower end machines. at any rate I wish I had conclusive evidence about the radiator, I have a gut feeling that although one may be more optimal than the other, if my experience from computers carries over even a poor raditor might only net a 10c difference in water temperature which is even more insignificant on a insulated torch with gloves on. My gut would be to go with what works best size/cost/weight-wise, as I think the cooling should be adequate finally you might try giving a welding supply shop a call, the ones that do machine repair. the guys who actually fix these machines for a living might have some more insight into the cooling loop workings.
