Stainless Steel Welding Decision

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So I have a decision to make and would like some input.I am building a home brew stand out of stainless steel 304 11 gauge and I have three choices.1. I can use my MIG that is a "Power Astro Mig" with 130 amps.2. I can have a friend that has a TIG but has never welded stainless steel before.3. I can pay a professional welder to do this for me.I guess my question is 130 amps enough to weld 1/8" SS tubing if I do this on my own? My machine says it can handle it, but after reading other posts in this forum I am starting to doubt it.  If I go this route I will have to buy 308L wire and a bottle of trimix which I know isn't cheap.  I really don't want to purchase this stuff if I am going to have to pay someone later to finish this for me.If I have my friend TIG it I will have to buy a tank of 100% argon and whatever else he would need - and I am not sure how good the results will be.  If he know hows to TIG regular steel, is stainless that much different?If I pay a professional welder they want to charge $85/hour.  Not sure how long it would take.
Reply:A stand is a bit different than a tank. I state this because I'm not 100% sure what you are thinking about.One issue with Stainless is what is refered to as "sugaring". That's where the back side of the weld is not shielded and gets these ugly crystal like "warts' for a lack of better description right now. It's usually an issue with thin stainless when used for tanks and piping, because that sugaring will trap and hold bacteria as well as reduce corrosion resistance of the stainless. It's the reason why most food grade stainless is welded with tig and back purged with argon or with a protective flux.This would not be as big a concern with a stand that supports the tanks. There mig should be fine. You wouldn't even have to use stainless unless you wanted to. My friends is just plain mild steel he painted. As far as structural strength of the welds, it depends on your design and what it has to hold. I'd use that little mig on 1/8" to support a 5 gal pot (45-55 lbs), but not to support a 300 gal tub ( 2400 lbs) for example. I simply wouldn't trust the welds  from that machine with something that heavy unless the design was over kill.It is possible to weld stainless with 75/25, but you loose the corrosion resistance in the stainless. Again not a big deal if it's just a stand and the stainless is mostly for looks. It's a bigger issue with tanks and so on where the corrosion resistance will make a bigger deal.As far as having someone else weld it, they should be able to give you a quote as to how long they think it will take if you have a drawing to show them whats involved..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:Where are you located?
Reply:This is a video of the brew stand I am trying to build - It is called Brutus 10.   The inventor of this stand is Lonnie Mac - in his instructions he used a Hobart 180 Mig with 100% argon gas.I am located near Annapolis, Maryland.
Reply:I work in a lot of food industries and stands are made from steel if a liquid form, and stainless if food will be free floating, like apples. I would use steel since your process will be done inside of a stainless tank. You only use 100% argon on mig aluminum, and all of tig.
Reply:I would have your friend weld it. It sounds like your application is not really going to come into contact with the beer, so if your friend doesn't do a perfect job no one gets hurt. But, in general, TIG on stainless is very similar to TIG on steel.Ian TannerKawasaki KX450 and many other fine tools
Reply:Originally Posted by Country MetalsI work in a lot of food industries and stands are made from steel if a liquid form, and stainless if food will be free floating, like apples. I would use steel since your process will be done inside of a stainless tank. You only use 100% argon on mig aluminum, and all of tig.
Reply:I don't wanna thread jack, but since its mostly on topic, would 75/25 gas be okay to use with the same 308L wire on 304 exhaust and one muffler that is 409. I was going to coat it all with heat resistant paint when I was done to give it a helping hand against the winter salt anyway so looks aren't as important.
Reply:Personally I'd prefer to do it myself, pride in the build and all! Your machine does sound a little small for 11gauge stainless! You could check with your local welding supply store alot of the ones around me actually rent machines for short term jobs! Then you could get a lease on a small bottle of tri-mix and get a small spool of wire! Then when you return the welder and the gas bottle you get most of your money back and you have a stand you can be proud of because you did it all yourself!
Reply:I'd have your friend TIG it.1) He should already have 100% argon.  Most TIG processes, and by 'most' I mean 100% of what a hobbyist would do, is done with 100% argon.2) Stainless TIG is very similar to TIG on mild steel.  In my opinion, 304 flows very nicely together.  Consider making one pass without filler and a second fill pass to build the bead.3) Sugaring on the back side can be dealt with either by a purge/shielding gas on the back side or with "Solar Flux".  A small quart size can is about $50 - but I believe you can get smaller packs now (like enough to do one job) for about $10 (best guess on price).  Purging odd shapes with gas is not trivial.  If you have a tight fitup, and you make the first pass fusion only (no filler), you might not get full penetration but you will not see sugaring on the back side - and have nice coloration on the front.  Not as strong, but most of the time plenty strong enough.  2nd pass build up the bead.  Blend it all in with a 120 (or higher) flap disk.  You can polish it out if you want.4) 308L filler is typically the No. 1 choice on 304L stainless.5) The thicker the stainless, the easier. (my opinion). especially when it comes to warping.On the MIG option.  Pure argon is usually avoided because of unstable arc.  Anything more than 5% CO in the mix will cause issues with corrosion resistance, strength and appearance.  Its all about controlling the carbon!  Special gas mix ratios can cost more and can be tough to come by in small quantities.  Tri-mix is relatively expensive, and even spools of stainless wire is expensive.One option you haven't mentioned is stick welding.  I recently had a choice between dragging my big TIG or MIG welder out of the shop on 50+ feet of extension cord, or pull out the little Maxstar to patch up an exhaust system (catalytic converter to unknown steel pipe).  I picked a specialty stick rod and turned down the amps (so I wouldn't burn through) and turned up the DIG (so I wouldn't stick). That was about 16 gauge.The flux coating will protect the weld.  Do this with good ventilation because of the chromium involved.Con Fuse!Miller Dynasty 350Millermatic 350P-Spoolmatic 30AMiller Multimatic 200Hypertherm PowerMax 1000G3Miller Maxstar 200DX
Reply:Cinpro,Tig welding the SS frame will give you the best strength/appearance.To mig weld that part, you really should be using a Tri-Mix gas.  The problem is, most gas suppliers only sell that mix in larger cylinders.  I keep a 330 on hand, but it's hard to justify for a hobbiest.  Ed Craig is a big proponent of a 98%Argon/2%CO2 mix, but I haven't tried it.I'm in Deltaville, VA (about 3 hrs from Annapolis--Used to live in Severna Park) and would be glad to weld the frame up for you if you wish to go that route.  From what I see, probably wouldn't cost you more than a bottle of gas.Used to make that drive every Friday/Sunday night.  Rt 50 to 301.  301 to Rt 17 in Port Royal.  Rt 17 to Saluda, VA.  Rt 33 to Deltaville.  Right at 165 mi.Syncro 250 DX Dynasty 200 DXMM 251 w/30A SG XMT 304 w/714 Feeder & Optima PulserHH187Dialarc 250 AC/DCHypertherm PM 1250Smith, Harris, Victor O/ASmith and Thermco Gas MixersAccess to a full fab shop with CNC Plasma, Water Jet, etc.
Reply:SundownIII - that is really generous of you - and I might take you up on that if my friend doesn't come through.  Weird enough - he actually lives in Severna Park.  I am still in the process of cutting the metal to length, and getting all of the parts together so hopefully I will be ready to go in a couple of weeks.
Reply:CK,What are you using to cut the SS to length?I use a bandsaw for most of the SS tube that I do.Have used an abrasive chop saw, but found that the cuts still needed to be "cleaned up" on the belt sander.Most of the dry cut saws really don't like cutting SS tube.  Really hard on the blade.Syncro 250 DX Dynasty 200 DXMM 251 w/30A SG XMT 304 w/714 Feeder & Optima PulserHH187Dialarc 250 AC/DCHypertherm PM 1250Smith, Harris, Victor O/ASmith and Thermco Gas MixersAccess to a full fab shop with CNC Plasma, Water Jet, etc.
Reply:Originally Posted by ckolliasNone of the beer actually comes in contact with the beer - the beer is in stainless steel brewing kettles.  I already have the stainless steel 304 tubing for the stand and am in the process of cutting it to length now.  Even though none of the beer will touch the stand, I would still like it to look good.  This stand will be on wheels so I can take places as needed.  The appearance of the stand will not effect the outcome of the beer however. I am curious to how this guy welded with a MIG and 100% argon gas?
Reply:98/2 argon/CO2  is pretty slick for spray transfer, not too great for short-circuit
Reply:Not to offend your friend, but welding is art/skill that takes years to get really good at.  You have a seasoned veteran who is not too far away (BTW, driving down 301 through Maryland s*cks, traffic lights every few feet), offering to do it for you, presumably letting you watch/learn.  That;s an easy one, do the drive (bring him lunch as well).Con Fuse!Miller Dynasty 350Millermatic 350P-Spoolmatic 30AMiller Multimatic 200Hypertherm PowerMax 1000G3Miller Maxstar 200DX
Reply:150 amps with tig will weld fairly thick material especially Stainless.......kinda wonder why your using 304?   most food processing vessels are made of 316L......better do more research before you poison yourself........lol  Miller Dynasty 350Twenty Six HammersThree Crow BarsBig Rock
Reply:Originally Posted by B_C150 amps with tig will weld fairly thick material especially Stainless.......kinda wonder why your using 304?   most food processing vessels are made of 316L......better do more research before you poison yourself........lol
Reply:Ok just checking ...... Lol  Miller Dynasty 350Twenty Six HammersThree Crow BarsBig Rock