Yikes 6011's !!!!!

Having to do butt joint test pieces using 2.5mm 6011's for a root run
in 6mm (1/4") mild steel plates bevelled 60 deg included angle. Root
gap is 2.5mm and root face about 2mm.
If I set the current to a 60amp @ 80v ocv starting the rod is VERY
painful, but eventually it runs ok, but I get all sorts of inclusions
from the false starts. If I go just over 65a to get a decent start I
burn nice keyholes in the root run.
Any tricks I can apply apart from bribing the inspector?
I'm limited to using a straight transformer AC welder so no foot pedal
tweeking allowed.
If I do the same runs in a 6013 rod they come out beautifully but 6013
aren't allowed :(
AWEM
Reply to
Andrew Mawson
Loading thread data ...
For 1/8" 6011, I will usually run at least 85-90 amps DC, so I suggest that the amperage is too low. Starting is not a problem.
For the burnthrough, 6011 has much more penetration than 6013. The electrode is 2.5 mm and the root gap is the same size. Since it's beveled, the metal is thin as well. For 1/4" plate with the penetration of 6011, push the test pieces together, then open the gap to a hairline separation. All that heat has to dissipate somewhere.
What tip manipulation are you using? Are you pushing or dragging along the weld seam? What is the angle of the electrode to the surface of the plate? Are you using a stepping motion?
6013 is a contact rod that can be dragged along the metal surface. 6011 is not a contact rod. What arc length are you holding? How big is the puddle?
These factors, including travel speed, affect the amount of heat fed into the joint.
Reply to
Thomas Kendrick
What is wrong with nice keyholes? You are supposed to get them.
Reply to
Footy
I would be using a bit more amperage. The trick to these is to spend time preparing your test pieces. I am guessing the bevel is done with a torch cut then cleaned with a grinder or better yet a belt ginder. After cleaning the edge whould be draw filed and checked with a straight edge. the land should be consistent and you should see no light under the straight edge put on the land. You can check your two pieces to make sure they go together light tight. Set your gap and tack weld one end then the other. Run your finger across the back. The plates should be even. If one plate is higher then your root bead will lose its tie in on one side. The tacks should be 3/4 inch long. Any shorter and they will shrink as you run your root. I like a bit tighter gap and thinner land but each to his own. You want the gap so that the rod will not fit through cold. If you get it right you can ride the tip in the bottom of the root. You will see little of the arc as the root is filled. If the joint opens up into a full keyhole then you have to slightly whip forward on each side to dissipate the heat. Randy
Reply to
Randy Zimmerman
As near-beginner, can comment:
Know good AC machine (oil-cooled "Oxford" arc-welder in UK) and 6011's keyhole the root beautifully. Bit offputting at first hearing mains-frequency crackle (unlike continuous sound when DC welding with same rod), but look and you see the joint is just fine - and it feels just the same to handle during welding (to my limited experience!).
70A recommended max. for all 2.5mm cellulosic - xx10 and xx11 (???)
Recall slightly higher amp setting selected when doing AC 6011 keyholing compared to exactly same rod used on DC welding set.
If current too high, cellulose starts to char on length of rod before getting into arc, degrading the shielding and arc penetrating power.
Shouldn't tell you this - found can go to 80A DC if soaked rods in water before use, then get stonking great penetration due to higher current, more hydrogen(?) and better-preserved cellulose going into arc (?) - but don't do this on a "coded" job!!!
My more extensive thoughts, released as "derranged insomniac musings on cellulosics welding"
formatting link
You are pushing the rod into the root of the joint and getting the keyholing action?
Richard Smith
Andrew Maws> Having to do butt joint test pieces using 2.5mm 6011's for a root run
Reply to
richard.smith.met
If the rod is sticking a lot, either your current is too low or your technique is lacking. I assume you are using the appropriate whipping technique for this kind of rod and know how to strike an arc. So I will concentrate on current.
Manufacturer's recommendations for 6011 I use is for 50 to 85 A for 3/32" (2.4 mm). So 65 A is right in the ballpark unless the procedure you are qualifying to doesn't allow it. FWIW current required with AC is higher than with DC. Also note that the specified amperage is at the electrode. What you think you set at the control may not be what you get at the electrode because of calibration issues with the control. The only way to know is to clamp a meter around the welding lead.
Also be aware that different manufacturers' 6011, and even different versions of 6011 from the same manufacturer, exhibit markedly different operating characteristics. One may run happily at 60A and another may not run well until you give it at least 70A.
Reply to
Footy

PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.