I recently got a a new to me TIG rig. Way more comfortable than what I used to have. My first project is a tool box for tig stuf. Long story but my neighbor left me a box he made in the AIR Force. It was on wheels waiting to tip. So, I made a dolly/outrigger for it. The TIG welds had longitudal cracking. I didnt take pics and its in use so, tonight I tried to recreate the crak using same materials and settings.It did crack but not as bad.I used an INVERTEC 250 lift arc, foot pedal at 200 amps. Helium at minimum flow. #8 cup, 3/32 gold lanthanated.The cracks are most visible to left of center. The welds seem strong but I dont like the cracking.On the dollie I used ER70s. No filler used in pic. Material is 1/4" by 2" platen.Why does it crack?BTW, I really like TIG'ng. No spadder. Attached Images
Reply:helium? wutwhy aren't you using argon?If the material regular mild steel? or something fancy or hardenedWelding/Fab Pics: www.UtahWeld.com
Reply:Use filler on steel. Grind to shiny metal. Argon is usually used for tig, when using helium you need higher cfh. Fill the crater at the end of the bead.Airco Ac/Dc 300 HeliwelderMillerMatic 200 (stolen)Miller Maxstar 150STLMiller AEAD200LE (welding and generating power) Hobart MIG
Reply:Its all I have. This is my second tank of helium. My whole TIG experiance is with the first 330cu ft tank.
Reply:I was trying to save helium using minimum flow. I will try turning it up. I want to try Argon but need to score a tank.Is lanthanted ok for mild steel?
Reply:Originally Posted by InsanerideI was trying to save helium using minimum flow. I will try turning it up. I want to try Argon but need to score a tank.Is lanthanted ok for mild steel?
Reply:I couldn't afford to use helium. That stuff is hard to find around here let alone finance 330cf.Teach Ag Mech - Mike At Home
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Reply:with all that rust and crud on it, I'd be surprised if it didn't crack.
Reply:............lack of reinforcement is the main cause..use filler.......could be cleaner too6 Miller Big Blue 600 Air Paks2 Miller 400D6 Lincoln LN-25's4 Miller Xtreme 12VS2 Miller Dimension 812 4 Climax BW-3000Z bore welders Hypertherm 65 and 85Bug-O Track BugPair of Welpers
Reply:I took more pics but I ground out the cracks. I tried turning up the flow and more cleaning prepping. I have to admit, I need to prep more than weld. Last night I made another weld. I got lots of soot. I think it was from not letting the acetone dry. Thanks for all the replys and cleen prep suggestion.The story on the Helium; I had the first tank before I had the welder but I knew it worked for TIG and I would eventually get TIG. When I got the INVERTEC, I started collecting TIG stuf. I thought I needed a water cooler and bookmarked Mikegyvers thread. Then I learned from this site about air cooled torches. I made a remote and used up the first tank. About year ago, I scored a second bottle of helium thru CL but traded my tig rig for welding stuf. I recently bought a TIG rig but only have helium. Helium seemed to be popular here a few years ago.1st pic TIG tool box2nd welds that were cracked but ground out 3rd last night weld with soot4th remote foot pedal Attached Images
Reply:The acetone should evaporate very quickly after starting the weld. I think you have a shielding issue if you are getting soot, looks like you ground it clean.Airco Ac/Dc 300 HeliwelderMillerMatic 200 (stolen)Miller Maxstar 150STLMiller AEAD200LE (welding and generating power) Hobart MIG
Reply:What cfh are you running the helium at?Helium requires a higher flow rate than argon - my guess is because it's lighter than air.I've seen references up to double the flow rate of argon.I tried it once when a buddy had only helium in the shop - I ran it over 30cfh on aluminum to get the results I was expecting.So it's more expensive and gets used up faster - I think you'll like argon better when you switch.Last edited by MinnesotaDave; 10-23-2014 at 11:47 AM.Dave J.Beware of false knowledge; it is more dangerous than ignorance. ~George Bernard Shaw~ Syncro 350Invertec v250-sThermal Arc 161 and 300MM210DialarcTried being normal once, didn't take....I think it was a Tuesday.
Reply:Helium is used for welding thicker pieces of metal at lower amperages, say quarter inch aluminum on an undersized ac tig. It can allow you to weld thicker metals that your welder normally wouldn't be good on. And helium will help in out of position overhead tig welds due to the density of it.You can also weld aluminum with helium using DC instead of ac. Just not near as nice as ac.Miller Dynasty Dx 200Miller bobcat 250Esab Miniarc 161
Reply:200 amps is way to hot especially when using helium.
Reply:Squirmy; I would think the pree-He flow would also evaporate the acetone. 10 four on shielding and I ground both sides this timeMDave: was set at top of ball to bottom line of 10 cfh on Argon side (no He scale). After Squirmy's suggestion to increase flow, I went to bottom of ball to top of line 10cfh. . I think a quality meter should be used for He but thats another discussionAwsome chart MDave. I knew a higher voltage was needed to ionize He compared to Argon but your chart gives values and temps. Also, it shows how poor He is compared to Argon for TIG'in in some circumstances I increased flow to top of ball to bottom of the 30 cfh line on the Argon scale. Other side is CO2 so this is a cheapo flow gauge since no He but I have to be in the ball park now.First and fourth pic is tonights weld at 30 cfh top of ball to bottom of line (normally I use middle of any gauge or middle of ball to middle of line but non linear gauges/meters confuse me) Second and third pic is molten Titanium with a couple Ti screws welded to it. I dont think He is needed to weld Ti but Ive wanted to weld Ti for a long time and you cant do it with 6010 or 7018 Attached ImagesLast edited by Insaneride; 10-23-2014 at 11:41 PM.
