ARC MAGAZINE

Can you provide any tips on running 308/309 uphill fillet weld with SMAW?
Mike Cabot, Happy Valley-Goose Bay, Labrador, Canada

The answer depends on which coating you’re using. There are three types: -15 (lime coating), -16 (titania coating) and -17 (silica-titania coating). Your best bet will be either -15 or -16. A -16 coating will be a little bit heavier, and will enable you to do flat, horizontal and uphill fillet welds. It can weld AC or DC, and can also be used out-of-position. A -15 coating, which is intended for DC use only, can handle just about any fillet weld—flat horizontal, uphill, vertical down and out-of-position. But the -17 coating is probably not a good idea. It’s primarily for flat horizontal fillet welding. It generally gets too soupy for anything else. If you wanted to weld 1/8 inch or 5/32 inch with -17, you might be able to push it if you’re an extremely skilled welder, but the more moderately skilled welder is better off using -15 or -16 for uphill fillet welding.

What is the main function or purpose of silicon in a solid welding wire (for example, 70S-3 or 70S-6)?
John Hindel, Chicago Ridge, Illinois

The silicon content in a consumable has an oxidizing effect on the weld that generally cleans the weld area. The -6 or -3 in the numeric designation of an electrode is an indication of the chemical composition of the consumable—generally the silicon composition—so a -3 electrode has less silicon than a -6 electrode. The greater the silicon content in the consumable, the better it can handle some rust and mill scale. The silicon also promotes wetting and makes the puddle more fluid, which enables the gases and contaminants to escape before the weld solidifies.

What would be the proper amperage and voltage to weld F22 material using GTAW and FCAW processes?
Julian Ortega, Houston, Texas

F22 material is aluminum, and you generally wouldn’t weld aluminum using the flux-cored process. Either TIG or MIG would be the more appropriate processes. When you TIG weld with F22, your voltage is adjusted by your arc length. Generally, you’re on a constant current machine, so you’re setting amperage, not voltage. Your voltage is dependent on how close your tungsten is to the work. TIG welding should be anywhere from 9 to 12 volts, and you’ll need to set your parameters for whatever type of material you’re welding. So it would be good to know the thickness of the material.

The nice thing is, you don’t have to commit these or any settings to memory; there’s an App for that! You can download the Lincoln Electric Weld Parameters Guide app on your smartphone or tablet, and it will walk you through the setup process based on weld process, material and thickness, electrode type and diameter, gas mixture and will give you the proper setup based on the variables you input.

As a beginning welder, I’d like to know what is meant by the phrase “weldable primer.” What is it, what is it used for and when?
Andrew M. Paradiso, Rochester, New York

Generally, the best welds are made with clean base metal, but in some cases, there needs to be a coating on the material to prevent mild corrosion. In these instances, the welder will use a primer that can be welded over without the need to clean the primer off. The most common primer is called Bloxide®, which has an aluminum oxide base. For best results, though, you want to clean your base metal before welding and avoid primer whenever possible, as it will degrade some of the properties of the weld. The same holds true for smaller home projects. It’s best to clean the base metal as thoroughly as possible, complete your welds, then coat the material or the part afterward.

When welding with a 6011 rod, why do you have to whip and pause, and why does it stick so easily?
Michal Wilson, Portsmouth, Virginia

E6011 or E6010 electrodes can be used with a dragging or whipping technique. The whipping technique is best for controlling the arc in situations where there are gaps or poor fit-up. The sticking happens when the electrode touches the workpiece, which results in a short. If the electrode sticks to the workpiece too long, it will overheat, causing the electrode flux to start burning. To whip the electrode properly, try to hold an arc of about 1/16 to 1/8 inch away from the workpiece. Keep in mind that the E6010 electrode is for DC polarity welding only. The E6011 is an AC electrode, but can be used with DC polarity (although AC is preferred).

From the welding experts at
Lincoln Electric