Fillet weld problems, need help please.

admin

I have been practicing my fillet welds on my MIG, and I don't have a lot of problems on the thicker stuff, but have big problems on the thinner stuff.The photo shown is one of my very first attempts at a fillet weld. It is on black steel at 5 mm thick. It was not that hard to attempt, and the MIG just pumped the heat in and everything was nice and smooth. Nice arc and pool, not a lot of splattering or hissing.When I swapped the heavy plate for thin galv it was a whole different story. I was trying to practice welding coffee table legs on out of 50 x 50 mm galv box tube at 1.6 mm thick.I turned the heat down a bit lower and did a practice run on a butt joint and the weld pool was nice and hot, everything flowed smoothly, with a nice consistent crackle sound.Without changing the setting I attempted the fillet and it was very hard to not get a lot of splatter, the welder was hissing (?) and spitting all over the place ?? Is this normal for fillet welding ??Should I turn the heat down even lower still ? or should I crank it way up ? It just didn't sound right with the gas and hissing sound ?Once I ran a bit of splatter over the joint (and that's all I could manage - 'splatter'), I could then manage to get a half decent weld over top of that, but not on first contact.Please help, it's frustrating me to the max I flap disked all the galv off the joints very starting my welds.
Reply:you didn't get the galv off...  It may have shined like it was off, BUT hot dipped galv isn;t going to come off with a flap wheel easily.  Take a grinding wheel designed for aluminum.  It will not clog up with the galv like a regular steel disk does.  then grind the crap out of it.I'm a Lover, Fighter, Wild horse Rider, and a pretty good welding man......
Reply:So it's the galv causing all the problems then ?
Reply:Hammack is right on it!Nothing more to be said.DavidReal world weldin.  When I grow up I want to be a tig weldor.
Reply:Yep he sure did you can tell by looking at it. Yes the Galv is causing the problem! Get the galv off and the weld should be easy and clean without that splatter. plus you sure do not want to be breathing that galv. That white power is the galv that wasn't removed by that flap wheel sander!!  Use a grinder.Co-Own CNC shop:Miller :1251 plasma cutter, MaxStar 700 TIG/Stick, & XMT 456 Multiprocess Welder.&  2 Hypertherm HPR260's Plasma CutterSorry I had a bad stroke but now I am back.
Reply:Originally Posted by specterYep he sure did you can tell by looking at it. Yes the Galv is causing the problem! Get the galv off and the weld should be easy and clean without that splatter. plus you sure do not want to be breathing that galv. That white power is the galv that wasn't removed by that flap wheel sander!!  Use a grinder.
Reply:eyspy,The weld posted looks like it needed to be filled in a little more. This can be done two different ways. You can slow down your travel speed or turn up your wire feed speed/amps. GMAW had 3 different transfer processes. First is short circuiting this is low volts = crackle and is best suited for thin or gauge steel thicknesses. next is globular this is a very narrow range and not really well suited for your application. Lastly is spray this is the hissing sound. It gives the best possibility of complete fusion. As you stated you had a set up where it was crackling on thicker material. This was short circuiting (SC). Then you went to  a thinner material and the sound changed to a hiss, this is spray transfer. The reason this happened is because there is a higher voltage requirement as your material gets thicker. By using SC setting that you had on the thicker material, for the thinner material,  you changed the transfer mode. But this this is just my opinion and is dependent on weather you are using a high Ar shielding gas."Religion is regarded by the common people as true, by the wise as false, and by the rulers as useful." -- Seneca the Younger
Reply:You can use a silicon bronze GMAW wire for thin galv work, and it works great ! Sort of like braze welding with the MIG.By the way, nice GMAW solid wire welds in the first postCheers
Reply:Thank for the tips.When I get a welder again I can practice. Some low life broke into my shed over the easter break and stole all my welding gear. My wife delivered our third child on tuesday 7th and I was too busy with tending to my other kids and in and out of the maternity ward to be in my shed.First time I went to my shed since the 7th was on the 11th to discover I had been burgled.Now I have to wait for all the insurance to be sorted before I can continue my welding journey.Sucks the big one..........
Reply:Sorry for your loss.  I had gasoline containers stolen from me in broad daylight, while I was here, in another building.  Why I have security cameras now.  With today's economy, thieves are becoming bolder and bolder.BTW, concerning your weld question.  You've received great advice.
Reply:Another thing with GMAW that is a good idea is to clean the mill scale off. If you look at the silica islands on the weld they look a bit dark. This is due to the mill scale. If you were to do another one and clean off the scale on half of it you should see the difference between the two."Religion is regarded by the common people as true, by the wise as false, and by the rulers as useful." -- Seneca the Younger
Reply:What does GMAW stand for ???
Reply:It is the standard name for mig (mig is a non standard term)"Religion is regarded by the common people as true, by the wise as false, and by the rulers as useful." -- Seneca the Younger
Reply:Thanks for that qaqc
Reply:Originally Posted by eyspyThe photo in my post is NOT galv, that was just a shot of my fillet weld on the 6 mm mild steel.I have since gone out to my workshop and ground off the galv on my test pieces a bit more deeper and had a go at welding it again. This time I had no problems at all.Thank you for the advice everyone, it was very helpful.
Reply:I believe that it has more to do with stress concentrations."Religion is regarded by the common people as true, by the wise as false, and by the rulers as useful." -- Seneca the Younger
Reply:Hey eyspy - sorry to hear about your theft. But congrats on the new kid!"We live in an age when unnecessary things are our only necessities. "   - Oscar WildeMaxstar STL150Eagle CPM30 Bender
Reply:thanks artworksmetal.The new kid is great, sleeps like a baby (pun intended)The insurance people came out yesterday and all is sweet. My new replacement gear should be here in days. Now I just have to learn my new welder all over again. My welder that got stolen was a MIG from Welding Industries Australia WIA, a 210amp remote feed that was built when things were quality built. That model is no longer available so now it get replaced with a WIA 256 amp remote feed ( http://www.welding.com.au/dw62-63/weldmatic-256/ ), which looks all spiffy, but the components would be sourced from China, unlike my old one which was sourced and made in good old OZ.Can't complain though as this new one is worth $3,500 Australian dollars.