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Stick Welding (SMAW)
Valerie Rock -
Friday, October 27, 2006 - 8:58pm
Welding SMAW SET-UP Here is some basic step-by-step set-up information for the arc welding process. Later on, I will elaborate on some of these points. If this sparks a particular question for you, please post a reply to this entry. Choose the electrode size, type and amperage range needed in relation to the metal to be welded. Choose the polarity (DCEN, DCRP, or AC) and connect the electrode and ground cables accordingly. For newer machines, this is with a switch. Connect the ground cable securely to the work or to the metal table that the work is placed upon. Turn on the ventilation. Check that you will not be positioned between "suction" type ventilation and the work. Obtain the proper shield lens and check it for cracks or pits. A "gold-bond" lens should be checked for scratches in the gold layer. Check that the electrode holder is not in contact with the grounded metal. Do not lay it on the metal table. Turn on the electrical power supply. At this point, an electric arc will be started whenever an electrode in the holder comes in contact with grounded metal surfaces. (Make sure that gas cylinders will never come in contact with the electrical arc!) Assume the machine is always ON. Insert the bare end of the electrode into one of the pairs of grooves in the electrode holder. Be aware of where you point the electrode. Position the electrode tip slightly above the metal to be welded. You will not be able to see where the electrode is until the arc is started once the helmet is down. Try to get a "feel" for where the electrode is in relation to the metal.Some people find it helpful to practice this with the machine off. Lower your helmet and swing the electrode down with a twist of the wrist. Scratch the surface of the metal. It is similar to striking a match. Then slightly raise the electrode from the metal, creating the desired arc length. (You will develop other techniques with practice.) If the electrode sticks to the metal, wiggle it back and forth to break it loose. If the electrode doesn't break off from the metal, squeeze the handle on the electrode holder to open the jaws and release the electrode. It is important to do this relatively quickly or you may overheat the electrical relays within the machine. After scratching the metal with one smooth motion, you should have an arc and should be able to clearly see where the electrode is pointing. Adjust the angle of the electrode to 12-20 degrees off of the vertical. Back away from the weld. Move in a relatively slow motion. Most welders use a slight side-to-side motion weave. The ripples in the finished weld, however, are not created by this motion, but by the back side of the molten puddle cooling as you move along. You will find that you need to continually watch that you keep the electrode height and electrode angle consistent. Move your body rather than twist your wrist to move along the metal. Otherwise, the angle of the electrode will continually be changing. To stop the arc, just pull the electrode away from the metal. (You may also need to fill the crater.) Don't melt the electrode down shorter than two inches from the end. The electrode stubs will be hot. One practice is to drop the electrode from the holder onto the floor and nudge it under the table with your boot. Then clean them all up at the end of the day. amperage and process
Valerie Rock -
Friday, November 3, 2006 - 1:15am
Great question, Richard! (Translated: I haven't been asked that before!) Q: Why does 100 amps when stick welding melt deeper than 100 amps on TIG or MIG? A: The electrode diameter is the main reason. Also the way the heat is transfered across the arc. The arc that comes off the stick welding electrode is a larger volume arc than the other two processes. It is a wider "stream" of electrons and also there are larger size "beads" of molten metal that are transferred from the electrode to the base metal. When MIG welding, you are using a smaller diameter electrode. Less amps are needed to melt the electrode and send the molten "bullets" of metal across the arc. These molten bullets and the small diameter of the electrode make a forceful arc that penetrates deeply into the base metal. (provided the volts and wire feed speed are within a proper range for the base metal thickness and gas used) In TIG welding, there is a small diameter electrode, but there is no metal transfered across the arc. It is an intense, narrow arc which concentrates the heat in a small area. On thin (<1/8") steel or stainless steel, a molten puddle is established quickly. Aluminum conducts the heat so well that much more amperage is needed to obtain a molten puddle. This is true even though the melting temperature is half that of steel or stainless! FYI: In MIG, volts and wire feed are the variables set on most power sources. » reply Syncrowave 180
jolly roger -
Saturday, July 14, 2007 - 11:13pm
I'm not Val, but here goes. You can run 5/32 on the 180, but you have to keep a close watch on your duty cycle as it will be loading it pretty heavy. The 1/8 shouldn't give you a problem unless you switch to 7018. Then again you have to watch the duty cycle. I have a syncrowave 250DX that I have never turned on (don't have the juice to run it yet) but I do seem to remember that they are not rated at 100% in the upper ranges. The duty cycle is the critical thing. I primarily use a 210 amp Lincoln that is rated at 100% at 210 amps and routinely run 5/32 Jet ((7024) should be about 180 - 200 amps) one right after the other. As for the one inch bar you shouldn't have to crank up the amps at all to get it to weld using the 6010. » reply the TYPE of SMAW electrode
welderguy -
Friday, March 21, 2008 - 12:50pm
the TYPE of SMAW electrode chosen has a lot to do with the penetration you achieve when stick welding. Cellulosic Electrodes » reply |
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Welding thick steel
Valerie:
I have been wondering why, for a given amperage, you can weld thicker steel with stick than TIG or MIG. I think that I have heard that if you use flux core MIG wire you can weld thicker metal than with plain wire and gas.
I have a TIG/Stick machine, Synchrowave 180, so don't have a ton of power. It seems adequate for what I do, I have yet to use more than 110 amps or so with 1/8 inch 6010 or 6013 rod. I don't have any 5/16 inch or heavier rod. On the TIG side, I rarely turn it up above 100 amps, but I basically use TIG for sheet metal. Not sure how thick I could go with 180 amps of TIG. Most of my welding is 0.043 inch copper, but I do weld steel to build tools.
By the way, how should I be welding thicker steel? (IE 1 inch square bar). I tend to just crank up the amps a bit and use 1/8" rod. I have some 3/32 inch rod for when I want to stick weld 1/8 inch or so steel.
Anyway, this is not a setup question, but it is related to stick welding. ;-)
Richard
http://www.fergusonsculpture.com
Sculptures in copper and other metals