Hi! I was taught to use a "whip" or "in-line stitch" motion when welding with 6010 rod. I have noticed that this makes nicer looking beads than a straight drag, but I don't really know why. Does anyone here know the theory behing the "whipping" or "stepping" motion? Thanks!
To keep the puddle moving to avoid burnthrough. To direct the puddle to different points you want to make molten and tie together. To fill in more of a volume. To reduce slightly the HAZ. To reduce warpage from excessive heat input. Lastly, appearance. Although a pretty looking weld that doesn't have fusion or penetration may not be as good as a gorilla weld that has melted the proper places, deposited more metal in the right places, but just looks like crap.
I don't know. That's a good question. My first (and oldest) instructor taught that technique but none of the others did. I think a straight drag makes a better looking bead - but that might just be an issue of taste.
I've had a lot more problems with getting a bend test to pass when trying to use the whip technique. It has a nasty issue of trapping slag and making the weld defective. I've given it up because of that and don't use it anymore. If there's some reason it's better, I don't know what it is. It might just be too advanced of a technique for me? :)
The only thing I can guess is that the whip technique is good at helping the welder control the heat in out of position welding so if you master it as the general technique for all 6010 welding it works well in out of position welds even if the amperage is set too hot. With a straight drag weld like I use for vertical and overhead, you really have to get the amperage set just perfect or it doesn't work. There's only a window of about +- 3 amps that a drag weld will work correctly in a vertical position (at least that's how it is for me).
But maybe, when the technique is used correctly, it produces better welds for other complex reasons I don't yet understand.
In the oilfield, 6010 is called "mud rod". It burns through a lot of stuff if you will keep the molten pool going enough to reach the rust, oil, grease, drilling mud, scale, paint, or whatever to boil it out in the puddle. 6010 is a good rod for dirty or rusty metal. It can and does work in a lot of bad situations. But it takes an operator who is seasoned in working with same.
The basic reason is that 6010 is an extremely aggressive rod and on a lot of material, if you just drag it, you will burn through the material or at least get some awful undercut.
The "whip" technique effectively pulses the weld, which gives you an enormous amount of heat control. How long you pause on the puddle, how far you whip and how long your arc length is, can be adjusted to suite a wide range of situations.
3 variations for a fillet weld progressing left to right.
The classic whip technique. Rod angle, 15 degrees up from the table, 15 degrees in the direction of travel. Arc length about 1/8". Strike the arc and pause for just under 1 second or a count of "1 thousand 1", then whip out quickly to about 1 inch, then whip back to an 1/8" forward of where you started. Repeat. Should yield a concave stack of neat little puddles down the joint.
Whip-push technique. Useful for poor fitup and filling gaps. Same as above, but after the puddle-pause instead of whipping to the right immediately, push back 1/2 inch over the previous puddles, then whip out as usual. It will eat the rod faster, but will fill huge gaps.
Root pass 6010.
1/16" arc length. Shove the tip of the rod right into the joint and rapidly whip back and forth, about 5/8" forward then 1/2" back, along the joint without any pause while progressing down the joint. This is vert fast and yields a very narrow, slightly convex weld bead intended as a root pass to be covered with 7018.
Lots of other variations, but you get the point. I teach 6010 and 7018 every month to a new group of students.
6010 is by far the tougher rod to learn, but is far more versatile than
7018 and will earn you more respect in the field.
For Schnicks and giggles try taking an 1/8" 6010 electrode. Set the machine for DC Electrode negative, and max out your amps. Dip the rod in water and lock it into the electrode holder. Set up a piece of flat plate and using a sawing motion you can slice 1" plate. You're lucky if you get halfway down the electrode before it just lights up like a sparkler, but is still a very useful technique to punch a crane lift hole or scarf off a lift point.
Has anyone here used a similar technique with short-circuiting MIG? I find that using a slight "in-line stitch" (similar motion to 6010 "whip", but much smaller steps and less agressive. I don't bring the arc out of the puddle, just right up to the leading edge of it. It is like I am using the arc to gently push the leading edge of the puddle forward a bit, then I bring it back a little way into the puddle and pause for a moment.) It seems to me that this yields welds with a better profile than I get with a straight push, as well as better control of the puddle when out of position. I find this to be true on most joints and positions.