Stainless back purging... what regulator?

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Sweet sugar from hell. I don't weld much stainless. Never been bothered with a little sugar and I could often mitigate it but today it went badly... so I hooked up a second bottle and reg. Taped everything up and went to town. This solved the sugaring problem. Yeah! But it wasn't 20 minutes and my regulator was icing over. Ok. I must be using way too much gas... even with the reg turned down to nearly nothing.School me on the proper back purge setup. I'm just using a reg off a wirefeed. So maybe I need something else? A different regulator? Or is frosting normal?
Reply:I just use the cheapo regulator that came with my MIG and I've never had any issues with it frosting up. I usually set it around 10 cfh unless it's something really big or unusually leaky.JohnA few weldersA lot of hammersA whole lot of C-clamps
Reply:Cheap regulator... check. I had it set at 10 CFH but it sounds like more. I thought it might be leaking but it's fine. I guess I'll try another regulator to try in the morning.
Reply:I have a dual flowmeter I'll sell you that would be easier and more convenient than 2 bottles. Its a metal craft made in usa.
Reply:Originally Posted by leeroy86I have a dual flowmeter I'll sell you that would be easier and more convenient than 2 bottles. Its a metal craft made in usa.
Reply:Frosting is not normal. Holy cow, how much gas were you purging with! YIKES.Just put a "T" on the regulator and 2 flow meters. You're making it WAAAAAAY to complicated with 2 bottles, 2 regulators etc. All you are doing it filling the inside cavity with argon, you don't need 10 CFM. You could use 0.5 cfm once the inside is inert, you are just keeping it above ambient pressure, with that much flow you'll probably be blowing out the puddle back into the torch if it's thin.RyanMiller Multimatic 200 tig/spool gun/wireless remoteMillermatic 350P, Bernard/XR Python gunsMiller Dynasty 350, Coolmate 3.5 & wireless remoteCK WF1 TIG wire feederMiller Spectrum 375 XtremeOptrel e684Miller Digital EliteMiller Weld-Mask
Reply:Wouldn't that take some spendy fittings to do that ^^
Reply:Can you post the T that your talking about xrayn
Reply:if you are not doing anything food related and you don't do much stainless this might be a better and cheaper set up.  http://www.solarflux.com/you can even order small batches, like 1 ounce on eBay ridiculously cheap
Reply:If its food grade then it has to be back purged with argon and tig welded.All the food grade pipe welding rigs have a regulator with 2 flow meters, one flow meter goes to the welder and the other one goes to a line.When I back purge a line the gas flow rate is dictated by the internal volume of the pipe to be purged and how fast I need it done. What I try to do is set the flow rate fast say 10 to 50 L/min to blow out the bulk of the air for a minute or 2 then set it way down low, so low that it doesn't register on the flow meter but so that I can just barely feel air leaving the 1/8 inch vent hole then let it sit for up to 30 minutes.Always use a gas diffuser or else you will be agitating the air and remixing it. You want to introduce the argon at the lowest point in the pipe and use the fact that it is slightly heavier than air to allow the argon to pool in the low portion of the pipe and push the air out as it rises.I guess if you are doing mig you might have to have 2 tanks, one for welding gas (trimix or contaminated argon) and one for pure argon. I have only ever tried to back purge with argon. An inert and 2% to 5% mix of CO2 or O2 mix might work as a back purge with mig.I will bring out the confined space "air meter" and test the air as its being purged out of the pipe, I find that a really good purge has about 0.5% oxygen, or about 2% "air" where I vent the pipe. So you could use mig gas to purge, it would just take more pure to get that active gas level down to around 2% or less.The only time I have seen frosting is when the contractors do a big job and bring in a tank of refrigerated liquefied argon.At home I just use 1 tank and one regulator. I tee the line and put in small 1/4 inch needle valve.Another option for non food grade, that you don't care what the back side looks like is solar flux, I use that on my little home SS tig projects.With solar flux what I will do for metal over 0.08'' wall is get the fit up as close as possible, then run a fusion weld as fast as I can across the back side let it cool, put solar flux on the fresh weld when its nearly cool then run a much hotter slower weld across the front.With thinner material 0.065'' and thinner I will fusion weld the front as fast and as ugly as possible, only gets ugly if fit up isn't great and I have to add filler, the only thing that matters is speed, sealing the front and back from each other with out sugaring. Then solar flux the back side of the weld, even up the weld with a grinder if needed and get full fusion and make it look pretty I use a much slower hotter technique like walking the cup.That way you get full fusion, it looks nice and no sugaring.You might be able to use solar flux with mig, I just have not tried it.old Miller spectrum 625 Lincoln SP-135 T, CO2+0.025 wireMiller model 250 and WP-18V torchCraftsman 100amp AC/DC and WP-17V torchCentury 115-004 HF arc stabilizerHome made 4 transformer spot welderHome made alternator welder
Reply:Originally Posted by motolife313Wouldn't that take some spendy fittings to do that ^^
Reply:I used solar flux for a project and it made me a believer in back purging with argon. It would work in places then not so much. I'm sure with practice I could get better but it felt like the inferior method. I'm sure it has its place.
Reply:To remove burned and used solar Flux I find that glass bead blasting gets rid of it pretty well. I just tried removing solar Flux with glass bead for the first time yesterday and it worked a lot better than I thought it would.old Miller spectrum 625 Lincoln SP-135 T, CO2+0.025 wireMiller model 250 and WP-18V torchCraftsman 100amp AC/DC and WP-17V torchCentury 115-004 HF arc stabilizerHome made 4 transformer spot welderHome made alternator welder
Reply:Originally Posted by xryanFrosting is not normal. Holy cow, how much gas were you purging with! YIKES.Just put a "T" on the regulator and 2 flow meters. You're making it WAAAAAAY to complicated with 2 bottles, 2 regulators etc. All you are doing it filling the inside cavity with argon, you don't need 10 CFM. You could use 0.5 cfm once the inside is inert, you are just keeping it above ambient pressure, with that much flow you'll probably be blowing out the puddle back into the torch if it's thin.
Reply:Here's a purge setup using one flowmeter and a Y connector with valves.  Other suggestions are in the thread as well.http://www.everlastgenerators.com/fo...Tig-purge-line"USMCPOP" First-born son: KIA  Iraq 1/26/05Syncrowave 250 w/ Coolmate 3Dialarc 250, Idealarc 250SP-175 +Firepower TIG 160S (gave the TA 161 STL to the son)Lincwelder AC180C (1952)Victor & Smith O/A torchesMiller spot welder
Reply:Whats a good diffuser to buy?
Reply:Originally Posted by MikeGyverlol its CFH, not CFM.a 10 CFM flow rate would be about 5 garden hoses worth of water.For purging stuff, once it's filled up with argon you'll typically be in the range of 5-10 cfh of flow (or more) depending on the area of all the cracks and joints added up. I basically never go below 5cfh. With everything totally sealed up and only a few holes poked in the taped off end (that's farthest from the purge inlet and highest up), you want to barely feel a positive flow coming out against your face.
Reply:Diffuser for purging?  Maybe something like this:  http://www.ebay.com/itm/like/1111725...&ul_noapp=truehttp://www.amazon.com/Aquarium-Relea.../dp/B00O0NLXFO"USMCPOP" First-born son: KIA  Iraq 1/26/05Syncrowave 250 w/ Coolmate 3Dialarc 250, Idealarc 250SP-175 +Firepower TIG 160S (gave the TA 161 STL to the son)Lincwelder AC180C (1952)Victor & Smith O/A torchesMiller spot welder
Reply:Originally Posted by OldendumHere's a purge setup using one flowmeter and a Y connector with valves.  Other suggestions are in the thread as well.http://www.everlastgenerators.com/fo...Tig-purge-line
Reply:Any diffuser from Walmart or a pet store for fish tank aeration would work.old Miller spectrum 625 Lincoln SP-135 T, CO2+0.025 wireMiller model 250 and WP-18V torchCraftsman 100amp AC/DC and WP-17V torchCentury 115-004 HF arc stabilizerHome made 4 transformer spot welderHome made alternator welder
Reply:Originally Posted by OldendumDiffuser for purging?  Maybe something like this:  http://www.ebay.com/itm/like/1111725...&ul_noapp=truehttp://www.amazon.com/Aquarium-Relea.../dp/B00O0NLXFO
Reply:Seriously guys you are making it WAY too complicated.  It's not rocket science.  Even then in building rocket parts it's not that complicated. Sanitary welding for food service, pipe for dangerous and explosive liquids and gasses etc. (Been there, done all that)  All you are doing is filling the cavity with a heavier than air 100% argon. You are also NOT pressurizing the space more than just barely above ambient, ie 0.1 psi as suggested with 5 cfh continual purge. You don't need any diffusers, pixy dust or unicorn horns.Sent from my SCH-I605 using TapatalkRyanMiller Multimatic 200 tig/spool gun/wireless remoteMillermatic 350P, Bernard/XR Python gunsMiller Dynasty 350, Coolmate 3.5 & wireless remoteCK WF1 TIG wire feederMiller Spectrum 375 XtremeOptrel e684Miller Digital EliteMiller Weld-Mask
Reply:The diffuser keeps from agitating the argon and air inefficient continuously remixing them. You don't have to use one but if you are cheap like me and don't like wasting argon then get one. A cheap fish tank diffuser is like $3.Saving a trip to the LWS or 3 to 10 cubic feet of argon makes it worth it.old Miller spectrum 625 Lincoln SP-135 T, CO2+0.025 wireMiller model 250 and WP-18V torchCraftsman 100amp AC/DC and WP-17V torchCentury 115-004 HF arc stabilizerHome made 4 transformer spot welderHome made alternator welder
Reply:I have a big 330 CF bottle rented. The little 80 cf bottle of argon is very expensive to fill. I've been trying to find a Tee with two females, and one male to attach to the big argon tank, then add two regulators. All Airgas has come up with so far is a three way female. They are still working on it.An optimist is usually wrong, and when the unexpected happens is unprepared. A pessimist is usually right, when wrong, is delighted, and well prepared.