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I've always thought, when MIG or flux core welding, you should "weave". I usually do semi circles. Now that I've joined this board, it seams like a straight stringer bead is not uncommon either. Now I'm confused. I'm assuming when you need to weld two pieces of metal perpendicular to each other, at a 90 degree angle, you would want to weave. If you were to butt weld two pieces together, and stringer would be good. Is this correct? I bought "The Welder's Handbook" on Amazon, it's informative, but when it comes down to technique, it's really lacking.
Reply:You mean a fillet?"Any day above ground is a good day"http://www.farmersamm.com/
Reply:I don't do a lot of solid wire welding, but I am well versed in flux core (both self and gas sheilded). In a fillet weld which generally looks like "L" a stringer is my preferred method. No oscillation or motion necessary just drag in a smooth motion. When doing a butt joint, you will generally have a backing plate with flux core. It is appropriate to use some motion to help the bead along. A weave can be used in vert up especially, but I have done vert up with stringers too. You can put some motion into a stringer and still have it end up as a stringer, but the moition is very minimal and referred to as an oscillation.I have found that it really depends on the welder's comfort and also the employer as to whether a stringer or a weave is used.
Reply:It all depends on fitup of course, but generally in wire feed processes, if you are using correct wire sizes and wire feed rates, there is little need to weave. A slight oscillation is all that should be required at most to tie the sides together. Anything more, you have an incorrect gun angle. Now, if you are running vertical, weaving may be necessary.But on a general fillet weld, correct technique, correct wire selection, heat, feed rate should not require weaving. Generally weaving in Mig is a heat control techinique.Esab Migmaster 250Lincoln SA 200Lincoln Ranger 8Smith Oxy Fuel setupEverlast PowerPlasma 80Everlast Power iMIG 160Everlast Power iMIG 205 Everlast Power iMIG 140EEverlast PowerARC 300Everlast PowerARC 140STEverlast PowerTIG 255EXT
Reply:Use a weave or sawtooth when welding fillets. Sure you dont have to, but most of the time an x-rayed GMAW fillet that used a weave will have a little bit better root penetration if welded correctly. Im talking structural here.Its really up to you or what a job calls for.I know folks that will never weave to save thier lives they run only stringers. And thats fine too. I guessAs far as myself, weave is the perfered for fillets on thick material like 1/4" and up.Always try and get the wire electrode into the corner and use an upward motion during your sawtooth or weave.Bottom line, when your a confident welder you'll know what use for what.Last edited by lewray; 01-03-2009 at 01:11 PM. weld it like you own it
Reply:Originally Posted by lewrayUse a weave or sawtooth when welding fillets. Sure you dont have to, but most of the time an x-rayed GMAW fillet that used a weave will have a little bit better root penetration if welded correctly. Im talking structural here.Its really up to you or what a job calls for.I know folks that will never weave to save thier lives they run only stringers. And thats fine too. I guessAs far as myself, weave is the perfered for fillets on thick material like 1/4" and up.Always try and get the wire electrode into the corner and use an upward motion during your sawtooth or weave.Bottom line, when your a confident welder you'll know what use for what.
Reply:Always seemed to me that a weave allows a greater chance of slag inclusion in the weld, but I don't do that much wire feed work to really know. I always stick with a stringer because it's easier for me.Now, that really helped, didn't it?"Any day above ground is a good day"http://www.farmersamm.com/
Reply:Originally Posted by farmersammAlways seemed to me that a weave allows a greater chance of slag inclusion in the weld, but I don't do that much wire feed work to really know. I always stick with a stringer because it's easier for me.Now, that really helped, didn't it?
Reply:How steady and straight are your stringers now? Some times I have enough shaking/side to side motion when I'm trying not to, that it weaves itself. I've learned to use this to my advantage over the years.
Reply:Originally Posted by BNFHow steady and straight are your stringers now? Some times I have enough shaking/side to side motion when I'm trying not to, that it weaves itself. I've learned to use this to my advantage over the years.
Reply:If a weave is used, more heat is needed to match it. The puddle has to remain fluid, so more heat is needed to keep it that way. This will float out the slag. Both methods work, depends on the job.David Real world weldin. When I grow up I want to be a tig weldor.
Reply:Thanks for all the advice guys. I want to experiment more with stringers and see how my beads turn out that way. Like i said, I usually use a semi circle pattern, or I do "lower case e's"
Reply:Originally Posted by BNFHow steady and straight are your stringers now? Some times I have enough shaking/side to side motion when I'm trying not to, that it weaves itself. I've learned to use this to my advantage over the years.
Reply:maybe this shoud be its own post.. but how much do let work in general cool before you put another stringer in, or weave over some stringers? David R says a weave needs more heat, but by the time ive got several stringers laid in next to each other, the piece is cookin hot...sometimes it seems like a weave over the top is just glowin..the heat stays in one spot longer when you weave than when you move out with a stringer...
Reply:Originally Posted by weldbeadmaybe this shoud be its own post.. but how much do let work in general cool before you put another stringer in, or weave over some stringers? David R says a weave needs more heat, but by the time ive got several stringers laid in next to each other, the piece is cookin hot...sometimes it seems like a weave over the top is just glowin..the heat stays in one spot longer when you weave than when you move out with a stringer...
Reply:thanks but im never gonna do anything important. i like to say i build shelves and craphooks...but i want very nice beads on them...my thought on stringers is they only exist so i can lay a nice weave over top of them....
Reply:Originally Posted by weldrwomnGenerally, if you are doing anything structurally important, you will have a procedure to follow. The procedure will tell you what the preheat, interpass, and postheat temperatures should be.
Reply:When mig welding, it can get too hot. The puddle control gets difficult and the weld can loose some of its properties. When filling a large bevel, if you get into too much of a hurry, you can boil the metal (lack of a better term) and the weld will crack. Each job is unique. Practicing on cupons is a good example. They do get too hot. Let em cool.David Real world weldin. When I grow up I want to be a tig weldor.
Reply:When I weld in the vertical position with GMAW or FCAW I have to manipulate the electrode. Even if I am making a 3/16" fillet. This manipulation reduces the convexity of the bead by spreading the heat out from the arc and depositing metal over a less concentrated area.As an inspector for a steel fabricator in the past I was involved in monitoring the welders techniques in some cases. In ALL cases in which the vertical fillet welds being made showed excess convexity or overlap, the welder was just putting the electrode in the corner and welding uphill.This effect can be noticed very easily by making a verical fillet weld using GMAW on maybe 2 pcs of 3/16" thick material. Using about 17.5 to 19 volts and some .035 wire adjust the wirefeed speed to your liking. Then make a vertical fillet weld without any manipulation OR triggering the gun.Then try one with slight manipulation < 1/16" to each side of center. Do the weaving very rapidly but with a distinct pause on each side. The pause does not have to be visible, just enough to feel it in your hands. Also do the pause with enough frequency that you are keeping most of the puddle molten.Then see if there is a difference in bead appearance.That is one type of "weaving". Here are some thoughts I have on that type of weaving.1) welds that are out of position are affected by gravity while they are molten. 2) welds that freeze faster are less affected.3) if the arc were to stay in the moddle of the puddle, the energy heat must 1st go through the molten weld metal before it is transferred away by the bas metal. If that is the case, the puddle stays molten longer and has more time to be affected by gravity.4) the weld metal is going to be molten no matter HOW you manipulate the electrode. 5) slight manipulation of the electrode will help spread the heat to the base metal more evenly.6) spreading the heat out slightly will help "wet the edges" of the puddle.7) spreading the heat out will reduce the amount of time the center of the bead is hot.8) for a given size fillet weld or volume of weld per inch, manipulating the electrode has NO effect on heat input if the parameters are the same.9) all of this is my opinion.The weave vs striger debate has gone on for a long time. Each has its place. In my 28 years of welding I have always manipulated the electrode when welding vertical. even if GTAW of 1/8" fillets. However to just randomly weave the electrode from side to side creating a large wide puddle is not suggested. Each joint, base metal, filler metal etc. may need its own techiques. A weave bead fills the joint at the EXACT same rate as stringers. As travel speed slows down, the amount of heat going into the base metal goes up. In some metals this can cause problems that can not be found by inspection after welding.Regradless of what method you use, be sure that the weld metal and base metal are fusing together. With multipass welds using stringers, the bead profile and placement becomes an issue. With weaving the visible bead contour may be able to be better controlled however the underlying fusion may be a problem if not done properly.All of the above is just one welders opinion. You can be sure to find many more. There are more details I have floating around in my head but I better stop.Gerald AustinHave a nice dayhttp://www.weldingdata.com/
Reply:I agree that a "weave bead fills the joint at the EXACT same rate as stringers" if you are only considering arc time. But you have to take into account additional cleaning time and non welding time between passes which may or may not effect the total cycle time of the weld.JTMcC.
Reply:Thats correct John. A short weld that can be done in one pass will be done quicker with one bead if it only takes ONE rod. But x amount of slag is x amount of slag. The only other difference is repositioning the welders body. I prefer doing as FEW arc starts as possible in one area. Thus the weave has some advantages there.Arc time can vary widely as far as its impact on production. Some guys gotta stop, look, smoke, etc every t ime the hood comes up. Others are only lookin for the next place to weld.Have a nice dayhttp://www.weldingdata.com/
Reply:[QUOTE=gaustin;241258] But x amount of slag is x amount of slag.QUOTE]Sure, but the number of times the welder stops welding, for the purpose of slag removal, effects cycle time.Say Welder Alpha is putting the cap on a 3/4" vertical up fillet with 7018, using a wide weave he makes the cap in one pass, he starts the cap and welds continuously (except for rod changes) till it's complete. Then the weld is power brushed one time, at completion.Next to him Welder Bravo is capping the same weld, same rod, with stringers resulting in a 3 bead cap.He stops welding two times that W Alpha doesn't, to power brush the slag after pass #1 and #2. Same amount of slag but at least twice as much time spent cleaning it.Or am I missing something here.JTMcC.
Reply:I gotcha. If he doesnt chip until a layer is done, then less time spent. I agree !Have a nice dayhttp://www.weldingdata.com/
Reply:It has been my observation that people often run too fast and too cold when first starting Mig. (Particularly in Ally) This can sometimes lead to an inclination to use a weave technique when a stringer will suffice. Too much deposition in a single pass can increase stress across the weld surface. Gun angle , lean back and point of aim (particularity when welding metals of dissimilar wall thickness's) can do the same .A weave will tend to mask some non optimal weld techniques and should be discouraged to some extent as multiple passes will help machine settings and technique assessment.A good guess is better than a bad measurement
Reply:Originally Posted by David RIf a weave is used, more heat is needed to match it. The puddle has to remain fluid, so more heat is needed to keep it that way. This will float out the slag. Both methods work, depends on the job.David |
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发表于 2021-8-31 23:52:53