Some advices about welding equipment, MIG and TIG welders, plasma cutters. MIG welders use a wire welding electrode on a spool that is fed automatically at a constant pre-selected speed. The arc, created by an electrical current between the base metal and the wire, melts the wire and joins it with the base, producing a high-strength weld with great appearance and little need for cleaning. MIG welding is clean, easy and can be used on thin or thicker plate metals. Similar to MIG welding, flux-cored arc welding (FCAW)* is a wire-feed process but differs in that self-shielded flux-cored welding does not require a shielding gas. Instead, flux-cored wire is used to shield the arc from contamination. This is a simple, efficient and effective welding approach, especially when welding outdoors, in windy conditions or on dirty materials. The process is widely used in construction because of its high welding speed and portability.
MIG welders guides: how to become a more skilled welder and how to choose the best welding equipment. 2% thoriated tungsten electrodes are mildly radioactive: Word on the street is that 2% thoriated tungsten electrodes are mildly radioactive. They say deer meat is too. No one gets out alive. Good news though…and it’s not just that I saved a bundle on my car insurance by switching to GEICO.. I have learned through testing a bunch of arc starts and by welding on all different metals that 2% lanthanated electrodes are about as good as the 2% thoriated. I even like the lanthanated a little better for some applications. So if you are scared of thoriated tungsten but you are even more scared of crappy electrodes that don’t work as well, use 2% lanthanated…they are colored blue. One word to the wise here. The blue ones are not brittle like 2% thoriated electrodes. And they splinter if you try to break them or snip with dykes. You have to cut or score with a grinder in order to cut to size or cut off a bib blob of metal you don’t want to sand off.
One of the “cardinal sins” that almost every shop commits is over-welding. This means that if the drawing calls for a 1/4″ fillet weld, most shops will put down a 5/16″ weld. The reasons? Either they don’t have a fillet gauge and are not exactly sure of the size of the weld they are producing or they put in some extra to “cover” themselves and make sure there is enough weld metal in place. But, over-welding leads to tremendous consumable waste. Let’s look again at our example. For a 1/4″ fillet weld, the typical operator will use .129 lbs. per foot of weld metal. The 5/16″ weld requires .201 lbs. per foot of weld metal – a 56 percent increase in weld volume compared to what is really needed. Plus, you must take into account the additional labor necessary to put down a larger weld. Not only is the company paying for extra, wasted consumable material, a weld with more weld metal is more likely to have warpage and distortion because of the added heat input. It is recommended that every operator be given a fillet gauge to accurately produce the weld specified – and nothing more. In addition, changes in wire diameter may be used to eliminate over-welding. Looking for the best Welding Fume Extraction? We recommend Welding Supplies Direct & associated company TWS Direct Ltd is an online distributor of a wide variety of welding supplies, welding equipment and welding machine. We supply plasma cutters, MIG, TIG, ARC welding machines and support consumables to the UK, Europe and North America.
Put a vent hole in anything you weld that will be sealed up completely: Put a vent hole in anything you weld that will be sealed up completely or air will heat up and expand and blow away your shielding gas or even blow out at the end of the weld bead. Some machined joints that are sealed on one end will not even allow you to start welding because the fit is so good that the part is air tight before you even weld. Other machined parts where a part is pressed in and bottomed out can give cracking problems because there is no where for the part to shrink. If you have to weld something that has been pressed in and bottomed out, make sure to add more filler metal than average to tacks and the final weld bead. That is to prevent the cracking that happens when you run a concave bead and the metal has nowhere to shrink.
Flat-Position Welding Increases Welding Speed : It’s common knowledge that welding in a horizontal position will be the easiest and fastest way to weld. A flat position is not as taxing to maintain and the welding puddle will stay in place. Take some time to evaluate each project before beginning in order to make sure the majority of welds can be completed in this position. If a job calls for vertical welding, see this article about vertical welding. Core Wire Feeder Increases TIG Welding Speed: For professional welders hoping to speed up TIG welding, a core wire feeder will add filler metal through an automated process. Watch this video on how it works. This enables welders to work with both hands and to maintain a constant flow of wire into the welding puddle. Ed Craig at the Frabricator writes about the wire feeder process first developed in Europe, saying it is “suitable for all-position welding on materials of any thickness, the process addresses traditional GTAW limitations and can enhance both manual and automated TIG weld quality and productivity.”
Improper drive roll selection and tension setting can lead to poor wire feeding. Consider the size and type of wire being used and match it to the correct drive roll. Since flux-cored wire is softer, due to the flux inside and the tubular design, it requires a knurled drive roll that has teeth to grab the wire and to help push it through. However, knurled drive rolls should not be used with solid wire because the teeth will cause shavings to break off the wire, leading to clogs in the liner that create resistance as the wire feeds. In this case, use V-grove or U-groove drive rolls instead. Set the proper drive roll tension by releasing the drive rolls. Then increase the tension while feeding the wire into your gloved hand until the tension is one half-turn past wire slippage. Always keep the gun as straight as possible to avoid kinking in the cable that could lead to poor wire feeding.
Just about everyone who tries TIG welding feels challenged at first. This is understandable, given all the things you have to watch for and think about, while simultaneously coordinating the motion of both hands. In most cases, a foot pedal or torch-mounted amperage control will be used — for starting, modulating and stopping the flow of current. I have coached many people as they learn these skills, and I have received my share of questions over the years. Here are a few frequently asked questions — and answers — that should be helpful, particularly for beginning and intermediate welders. Source: https://www.weldingsuppliesdirect.co.uk/.