help vertical stick weld

my brother is taking welding class through his union shop. stick welding in vertical motion is a nightmare and he is not able to get a smooth pass.

instructor says to zig-zag in "Z" fasion, holding rod slightly up from perpendiculat to the weld surface, using 3/32" 7014 rod on lincoln ac unit.

any advice to get smooth pass ??

thanx.

Reply to
Kryptoknight
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Pause at the end of each Z. It is called a Z, but don't make the center leg too much of an incline. Pause slightly, and when you get the start of a puddle on the end of the Z head back the other way.

Could show you in about 15 seconds. Could describe it in about 1500 words .................

Steve

Reply to
SteveB

Reply to
dogalone

A standard left to right weave as you move upward should go like this: The rod should be horizontal to tipped up around ten degrees. I have seen people do nice passes with the rod tipped up as much as 45 degrees. I don't recommend it. The speed and amount of hesitation on each end is much like a waltz. " One - Two_Three- One- Two- Three" Two and Three are spent one each side of the weave. The one part is spent travelling across the center. The amount of time spent in the middle is minimal since you don't want a large puddle in the middle that will run. You can waltz fast or slow, it is up to you but the proportion of time spent in the middle is the same. The slower you go the heavier the buildup on each pass back and forth. The ripples also become larger. The faster you go the finer the ripples and the advancement upward is less each weave. You do not move upward at the hesitation. You move upward as you move across the face of the weld. Now for your eyes! As you are moving back and forth you are creating a crater on each side then filling it as you move back ino the cooling crater. You start say on the left and as soon as you have a puddle created you move to the right and create a puddle on the other side. While you establishing the puddle on the right put your eyes on the left puddle that is cooling. When you return you want the end of the rod to end up slightly above the cooling puddle. You swing over to your left and place the rod on your target location. The molten metal will roll under and fill that cooling crater. Your eyes should now be looking at the right hand puddle as it starts to cool. You are now on "one" and swinging back over to the right slightly above the targeted crater. Move too high each pass and you create undercut and a missing section of weld. If you do not move high enough then the crater becomes too large and lumpy and now end up with a grape on one side. Last thing to watch for is the colour difference between molten metal and molten flux. The flux is a bit more orange. Many people panic and think their weld is running when what they see is the flux rolling downward over the weld bead. The rod is an odd choice for a beginner. Doing it with a cellulose rod first is a more efficient procedure since it is a fast freeze rod. The puddle of a 7014 is very slow cooling because it is iron powder flux with high fill characteristics.

Randy

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Reply to
Randy Zimmerman

A rod that has a cellulose coating, IIRC.

Steve

Reply to
SteveB

I am dumb what is a cellulose rod?

Reply to
williamhenry

The first welding rods were bare steel wire rods with no flux. The next step was to wrap newsprint around the rod with waterglass to hold it in place. I have actually seen one of these old rods on display in a vocational welding shop. The present cellulose rods are E 6010 and E 6011. The coating is cellulose based. In other words wood fibre. When you weld the wood /sawdust /woodfibre burns and uses up the oxygen to produce carbon dioxide. The hydrogen component of the cellulose turns into water or rather steam at that high temp. The hydrogen floating around ends up getting into the molten steel in the form of small bubbles that can be crack sites at a future time. This is not a problem with mild steel. Low hydrogen rods have flux coatings made up of things other than hydrocarbons. The nice thing about cellulose rods is that they are fast freezing so that as soon as you move out of the puddle the weld cools rapidly. The flux is thin and the gaseous cloud protecting the weld is massive compared to other types of welding rods. It is relatively easy to see the molten metal as you work the puddle. The fast freeze aspect is helpful for a beginner trying verticals. Randy

Reply to
Randy Zimmerman

wow, that has to be the most helpful reply I have ever received, thanks

Reply to
williamhenry

I recently started teaching a welding class and have noticed that they all had to be shown how to steady themselves so they could place the rod precisely where they wanted it to be . I was amazed how steady they were considering that they were standing in the middle of their weld both holding the rod holder out and not touching anything . They were steadier than I am not resting or holding onto anything but you can NOT make steady and precise wrist movements unless you have your body supported and your arm movement unrestricted. Have you ever threaded a needle? You have to rest one hand on the other to place the thread into the hole . Well a smooth weld incorporates the same concept . Everyone that lays down consistent beads supports themselves !!! As for the mechanics of working with molten metal . A puddle that starves for metal will suck molten metal from the base plate ,this is the cause for under cut .As you weld the heat or amperage setting along with the type and diameter rod will melt a certain amount of metal . The size of this puddle is also influenced by the thickness and type of metal along with the temperature of the base plate . One more variable is the arc length A short arc length ,rod touching the puddle , concentrates all its heat into a smaller area and into the base plate . The puddle that you get with this tight arc fills up fast and cuts down on under cut . When you lengthen the arc it spreads out more , makes a bigger puddle and pulls metal from the base plate until you stay there long enough for the melting rod to fill it up . Surface tension or molecular attraction is the force at play here before gravity starts to over powers this attraction . All welding works around these forces . You also have the rate at witch metal dissipates heat that effects the puddle . This is why when you change the thickness of metal or amperage or joint configuration you have to redial your technique . The rod burns at a certain rate of speed at a certain amperage laying down a steady flow of metal . The amount of metal that it adds to the puddle is one thing that regulates your welding speed . The size of your puddle determines how much metal you need to add to it . Your amperage is the basic factor deciding the size of your puddle . You already made the decision as to what rod which diameter and if it wasn't for the metal you have you wouldn't be welding . When welding you generally have two pieces . You weld one plate to the other so you have to add heat to one plate fill the puddle then add heat to the other plate . The middle is weld you don't have to weld weld so pay no attention to the space in between the sides . A molten puddle will seek it's own level , remember this . When the metal is no longer molten then it needs to be reheated . This comes into play when the puddle gets wider . When the middle bulges out then you either have to make a thicker puddle to hold the volume of molten metal (pause longer on the sides) or turn down the heat to make a smaller puddle . This will give you something to think about under the hood .

Reply to
Lewis Edwards

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