Penetration Vs Fusion

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I have seen quite a few questions about this, so I did a test to see what happens.  I think good fusion is all you need for a good weld.  The test.  3/8" cold rolled with mill scale removed.T or fillet weld, one doe in one hot deep penetrating pass.One done with multiple passes at a much lower setting..045 wire, 92/8 gas, Pulsed Spray Mig.ONE hot pass 400 ipm, 338 amps according to the meter.Other one 5 passes at 150 ipm, A little over 100 amps, I  can't remember exactly.I made + with the 3 pieces.  Put one in the vice and got on the other one with a 18" crescent wrench.  Both beads were a root bend.  Make your own conclusionsMultipass is on the leftSingle pass brokeBead profiles.  Miltipass on the right.Trying to show penetration.  Something about laminar tearing or heat affected zone.  Where is Pulser?Last edited by David R; 01-28-2008 at 05:32 PM.Real world weldin.  When I grow up I want to be a tig weldor.
Reply:Here is the piece I cut off the end before the test etched. Deep penetrating single pass is on the right.The piece of 3/8" on the left (fusion) bent before the weld bent.  The deep penetrating weld just tore the plate.Last edited by David R; 01-28-2008 at 05:34 PM.Real world weldin.  When I grow up I want to be a tig weldor.
Reply:But WAIT theres MORE!I wasn't quite satisfied, so I did it again.  This time 2" wide pieces of 3/8" X 4" plate.  Welded on the END (against the grain?).  This made both beads 2" long instead of just guessing.  I have a bead gauge, but the pics didn't come out.  Beads were close in size is the best I can say.I turned the wave control down on the machine and traveled slower to get a more convex bead on the single pass.  Multipass was done the same as last time.  I could not fit this one in the bandsaw to cut and etch it.Single pass5 passesSingle pass is on the left.  The multipass weld broke right down the center of the weld.    Draw your own conclusion.David Real world weldin.  When I grow up I want to be a tig weldor.
Reply:You have demonstrated the old school thinking. That a single pass done right is a weld, and that is all you have in reality. No matter how many other passes you put on. Many hard core welders, even myself on occasion will think for a second "Add another pass.....". But I know better. The problem is leverage point. As you add more weld, you alter the leverage point. You stress the un- welded material more. That is great, though. For those that do not experiment you have at least gotten it into their mind for inspection or contemplation.        Sincerely,             William McCormick
Reply:dave, that is some great comparisons. I would have thought the multi pass would have been stronger. Learn something new everyday.G3miller... 225g, s32p, 250x, 304, 12vs, MSW41     victor o/a thermal dynamics cutmaster 50 lenco panel spotter        hobart hf-boxG3 Farms.....raising cattle, hay, kids and hell, ...oh yeah I'm a fire sprinkler contractor by trade.
Reply:Looking at how much the 2" wide 3/8 plates each bent, I would say they are close.Single pass broke the first time, multipass broke the second time.DavidLast edited by David R; 01-28-2008 at 08:47 PM.Real world weldin.  When I grow up I want to be a tig weldor.
Reply:In AWSD1.1 the macro etch test wants to see fusion to the rood and not necessarily beyond. D1.1 further says that for SMAW no single pass fillets grater than 1/4" and 5/16 for FCAW GMAW.At some point in AWS D1.1 ts states no weave beads stringers only. While the test you did is very interesting I would not conclude that a single pass weld of X dimension is stronger than a multi pass of the same dimension. Also you are not really testing penetration vs. fusion as both are required to achieve a sound weld. A weld with 100% penetration and poor fusion vs. a 50% penetration and sound fusion I have know doubt the 50% penetration will pull at a grater  rate. (as in tension) And depending on the location and severity of the nonfusion the 100% coupon might just fall apart on its own.None the less interesting and the only way to understand your skills as a welder is to destroy some of your work from time to time..Jimmy
Reply:Jeez man! I like your posts so much...I think that it shows how a properly fused weld can achieve pretty much the same strenght as a good penetration weld. However 100 amps for the 3/8 plate seems too little. Heat should´ve been sucked instantaneously by the thick plate. As worldsgreatestwelder says according to some standards fusion is the only thing required. And according to what I´ve learnt in some classes most machines are designed according to the the same principles.Of course penetration never hurts My Babies: HF Drill pressHF Pipe Bender3   4.5" Black and Decker angle grindersLincoln Electric PROMIG 175that´s it!
Reply:David R thank you for bring this up i was getting sick of hearing about penetration of the weld  wile you need it ,you still need a properly fused weld and turning up your machine to get more penetration in sted ofchangeing joint desigan is not allways the way to go.elvergon and worldsgreatestwelder thank you guys too ChuckASME Pressure Vessel welder
Reply:Excellent, and interesting, post!  This kind of flies in the face of what many, myself included, was either taught or understood.  I like this comparison, informative to say the least .Have a Jeep Cherokee?  Click Here!
Reply:Thanks for that demo David RI learn something new everytime I log on here
Reply:So....for all intents and purposes, since a lot of us are not doing welds that are inspected, x-rayed, or cut and bent..... What are we concluding? I say, you should have welded the opposing side of the pieces. Then you have two filets!! ahahaLincoln Power Mig 210MP MIGLincoln Power Mig 350MP - MIG and Push-PullLincoln TIG 300-300Lincoln Hobby-Weld 110v  Thanks JLAMESCK TIG TORCH, gas diffuser, pyrex cupThermal Dynamics Cutmaster 101My brain
Reply:?? As a new person to welding. My question is: Why did you bend the toward the side that was welded?BrucePeople are more violently opposed to fur than leather because it's safer to harass rich women than motorcycle gangs.  Unknown Pro Mig 175Hyphertherm 600Lots of toys at work
Reply:Originally Posted by dangthatshot?? As a new person to welding. My question is: Why did you bend the toward the side that was welded?Bruce
Reply:Great piece of show and tell Dave!!And then, after so much work...... you have it in your hand, and you look over to your side...... and the runner has run off. Leaving you holding the prize, wondering when the runner will return.
Reply:David it's fantastic the way you take the time to do these tests and photograph them so clearly. Many thanks for taking the time and making the effort. Scott
Reply:David, as always, your weld experiments and write-ups are very much appreciated!I nominate David for a new title on the board:  Welding Scientist! ...or is that called 'weldologist' ??.Last edited by DesertRider33; 01-29-2008 at 01:22 AM.MM350P/Python/Q300MM175/Q300DialarcHFHTP MIG200PowCon300SMHypertherm380ThermalArc185Purox oaF350CrewCab4x4LoadNGo utilitybedBobcat250XMT304/Optima/SpoolmaticSuitcase12RC/Q300Suitcase8RC/Q400Passport/Q300Smith op
Reply:David penetration of the weld and multi pass welds are two different thingsChuckASME Pressure Vessel welder
Reply:A couple of notes.I did a root bend because I sure as HELL am not strong enough to do a face bend.  It also tests how well the weld grabbed (fusion) the plate.  The etched weld on the right (one pass) looks like the pic in the book.  3/8" plate, 338 amps.  Thats a lotta amps.  If you look at the one pass, the weld didn't budge, the metal tore next to it.  could have been from so much heat.  I am not a scientist and do not have a lab, just a slow day in my shop.I Pulse spray migged them.  Pulse spray uses HIGH amps and LOW amps at about 200-300 Hz.  The puddle is wet, the metal is sprayed on like paint, so I know I have fusion.  A little mill scale and the whole thing would have come out different.I went overboard as usual using the low setting. But it did prove my point.   If this was plain mig, it would not have worked.  Maybe with small rod and big rod.......HEY!........NEXT time....7018.  I do have some 3/16" atom arc.   I'll throw it in the oven for another day.Thanks for all the compliments.  Like I said in the first post, draw your own conclusion.Dangthatshot, I love your sig.DavidLast edited by David R; 01-29-2008 at 06:18 AM.Real world weldin.  When I grow up I want to be a tig weldor.
Reply:David R thanks so much for the great test and pics..
Reply:Dave, a couple of things."...I sure as hell am not strong enough to do a face bend ..."  Awww, come on man, use a cheater bar or some hydraulics!  Next, thanks for the experiment.  The cut-polish-etch is quite decent to show folks (us!) where the weld is and how much fusion and penetration did (or did not!) occur.Now about that penetration and fusion ...Your welds in these experiments showed pretty much that you had OK fusion to the base material.  Your welds melted into the plates nicely for the most part.  A little iffy on the multi-pass attempt regarding the fusion into the 'main' plate, IMHO.But .... Pretty much all of these welds were CRAP in regards to penetration!Look at how -little- penetration into the plates there is.  I drew the approximate center line down the plates in red.  An approximate half-way chamfer is in the blue-aqua color.  Your welds, single pass or multi-pass, are nowhere even -close- to either half-way mark!  And that's just to get halfway.Penetration?  It was minimal.  Yeah, you peeled the weld (or part of the plate) right off of the add-on plate because that's only as deep as your weld went. Lamellar tearing, and all that.I mean, that single pass pulsed weld is pretty, and consistent, and everything.  But it is also pretty much just kissing the surface of the plates and didn't get -into- the plates.  You need to get that deepest part of the weld penetration down where the red and yellow center-lines meet, and that's if you are going to weld both sides of your fillets.Take your 3/8 plate, bevel prep the edges, and then run your hot single pass pulse spray.  Cut, polish, and etch and see where and how deep the weld is then.  You'll probably need a BIG cheater bar to try and bend -that- sample!Take that 3/8 plate, double -bevel prep the edge, and fillet weld both sides for complete penetration.  Then -try- and bend it with your wrench!    That plate should bend right over (with some big cheater bar on it) and the weld won't even budge.I do appreciate your work and the time and effort you put into this demonstration.  Thank you. Attached Images
Reply:Originally Posted by MoonRiseDave, a couple of things.Pretty much all of these welds were CRAP in regards to penetration!Look at how -little- penetration into the plates there is.  I drew the approximate center line down the plates in red.  An approximate half-way chamfer is in the blue-aqua color.  Your welds, single pass or multi-pass, are nowhere even -close- to either half-way mark!  And that's just to get halfway.Penetration?  It was minimal.  Thank you.
Reply:Ummm, nope.  He didn't -penetrate- through the solids of the plate.  He -did- fuse the weld bead(s) to the adjoining -surfaces- of the plates.If David had done a bevel prep on the plate before running the weld bead(s), the fusion and the penetration would have been closer to the same thing.  But he didn't, so the fusion was only on the -surface- of the plates.  And the surface of the plates was on the ... surface of the plates.Look what his etch shows.  The weld does join the surfaces of the plates, where ever it touches the plates.  But for the most part, the weld does not go -into- the plates much.  He did get better penetration of the weld into the 'main' plate and not the 'added' plate (which to me is slightly counterintuitive because the main plate has bigger thermal mass and he's in the middle of it while the add-on plate has an edge that -should- have melted more).Look at the first marked-up pic.  See how the weld barely gets past the projected red surface lines?  See how long the blue-aqua line on the add-on plate is, showing how much of that plate is not attached to the main plate and is just 'swinging in the breeze'?  As soon as David applied his wrench and the bending load to the weldment, the add-on plate just peeled right off of the main plate.  Because the only metal holding the plates together against his wrench is the little bit I outlined in white.The stress on that little bit of weld area (the white outlined bit) when he cranked on the end of the add-on plate is HUGE!!!!  He just peeled the plate open like a pop-top.Now look at the second attached marker-up pic.  If he had bevel-prepped or ground out or gouged out the joint area and then welded it up to get a weld that -penetrated- into the plates more along the purple sketched lines, he would have had 100% penetration through the joint and that joint would have been stronger than the base plates.  Even with a cheater bar I don't think David would be able to break THAT weld.Ahhh, I think I see what you are getting at.  As long as the weld fuses into the parent material and the upper area of the bead doesn't exhibit undercut or concavity, what more do you need, right?  I fully agree, IF the joint is sized or prepped to allow the weld to join all the edges and surfaces together!For a single-sided weld on that 3/8 plate, a deep U-groove prep may work out.  Look at the last marked up pic I attached here.  Prep the groove like the blue-aqua sketch indicates, and then weld it up and you should get a weld close to the white sketch.  Might have to adjust the depth of the groove and the weld parameters to 'dance' together to get full penetration without blowing out the back of the joint when welding it.  But it's all pretty much like doing a pipe weld.  You have to get the root pass to get to the ID of the pipe, and then the fill and cap gets the rest all together.  The end result is that you have weld metal joining all the parent metal together and you don't have voids or air or discontinuities between the metal, you just have one continous weldment.And David did NOT get "full penetration to the root and beyond, in both directions."  Full penetration to the root on a single-sided fillet weld would be as I sketched in white in the last pic. Attached Images
Reply:OK MooRrise, I'll get out the bible, pics and all.  A weld should be as deep as it is wide.  That weld measured 5/16 using my gauge.  It should be .44" across the bead and .44" deep.  Can you measure that?  I am not that good with a puter.  5/16 fillet is aws for 3/8 plate.  And no we are not supposed to go over a 5/16" fillet. If I added 3/16 (1/2 the plate thickness) my weld would be .44" wide and 1/2" deep.  I don't think I need to go 1/2 way into the plate, Just have 5/16" of good fusion on each plate with a flat bead.   I said in the first post, draw your own conclusion.  Yours is my welds are crap    Its just a weld.David Edit:  Credit for page to Procedure hand book of arc welding by LincolnLast edited by David R; 01-29-2008 at 06:56 PM.Reason: creidtReal world weldin.  When I grow up I want to be a tig weldor.
Reply:MoonRise you posted when I was   Its not a big deal.  I did the test.  I think the "deep penetrating weld" Looks just like the ones in the book.  Today I did a stick attempt.   I can't run 3/16" 7018 @ 280 amps for 2" and have control.  The multipass with 3/32 7018 @ 90 amps was pretty and held up better.   A couple of questions for you MoonRise.  If I had a 24' X 1/2" piling I had to fillet weld end to end, how would I bevel it?How many amps and what rod (process?) do I need to get a full penetrating weld.  I don't think I got big enough stuff to reach to the other side of the 3/8" plate.David Real world weldin.  When I grow up I want to be a tig weldor.David, the weld (well the single pass pulsed MIG weld anyway) is beautiful.The penetration of the weld on that plate with no joint prep other than cleaning was crap.  The shape of the weld is beautiful, it's just that there is all that unjoined metal between the two plates.And no sarcasm here, just straight-up Thank You for doing all these tests and posting them for us to see.  That cut-polished-etched picture is a beaut.
Reply:Oh Jeezzzzzzzzzzz..Here we go yet again..Sometimes its best to agree to disagree..And leave it at that!What do you think would happen to the piece if all sides were done??...zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:I see no sarcasm.  I see no name calling etc.....If it this wasn't fun, I wouldn't do it.  I don't see in my world where its worth the time to bevel a fillet weld.   A fillet or a lap are the only "natural" joints.   A butt weld needs some kind of groove.  If I welded both sides of  that T joint, I don't think anyone could break the welds. Do you bevel for a 3F test?  I only took the 3G.You gonna answer my questions?Edit to answer one.  The Bible (Procedure hand book of arc welding by Lincoln) sez 3/8 plate, 5/16" fillet in one pass  1/4" 7018 @ 350 amps.David Last edited by David R; 01-29-2008 at 06:55 PM.Real world weldin.  When I grow up I want to be a tig weldor.
Reply:A fillet weld only requires fusion to the plates, not penetration into the plates, unless penetration is specifically called for on the drawing/specification.In comparing one large single pass fillet weld with an equal size fillet produced by three stringer beads, I think there is reason to believe that the multipass stringer fillet could have better impact and toughness properties.The heat affected zone (HAZ) adjacent to the weld bead on carbon steel will have undergone grain growth and possibly hard brittle martensite formation depending on carbon content and cooling rate.  These factors reduce the toughness and impact strength of the HAZ.  Smaller grains produce a more tortuous fracture path along the grain boundaries that resists cracking better than just a few big straight grain boundaries.One large single pass fillet will have a large HAZ, whereas in the fillet composed of three stringers, the HAZ of each bead will be smaller and probably add up to less area than the single pass.  Also, after the first pass, the subsequent passes act to temper, stress relieve, and drive off any hydrogen picked up in the previous beads and HAZ to some extent, and some of the coarse grain structure of the first HAZ may undergo recrstalization, thus restoring a finer grain structure.As far as I know, for any large fillet or groove weld, the stringer bead method is much better for impact toughness than a big ole single weave pass.
Reply:More comments. The last pic in post 3 which was the second test I did with out etching the plate, I could NOT get that piece off the plate.  I needed it off so the piece would fit back in my bandsaw to do the stick test.  I could not break it off with an 8lb sledge hammer.  I put it in the vice and cranked away.  Finally I got out the carbon arc and bunt it off.  That weld was as strong as the plate.  It was done the same as the first test.  The bent plates show how strong the weld was compared to the plate.DavidReal world weldin.  When I grow up I want to be a tig weldor.
Reply:MoonriseWhere are you getting you information and definitions?Some how you have equated "penetration" to "Complete Joint Penetration". They are two separate things. It is acceptable to many codes (as well as practical application) to have a fine weld fully to code that has limited penetration. When inspecting welds (I am a AWS CWI) the first consideration it given to the toe of the weld, looking for non fusion, undercut and cold lap. Next is weld profile, looking for inclusions non-fusion and other discontinuities. Is the weld in conformance to the code and the called for weld.     Never during a visual inspection is an inspector asked to determine the amount of penetration, as it is visible. Your point that a better connection could be had, is immaterial. Using bigger material and bolts might do just fine with out all the mess of welding. Jimmy
Reply:Moonrise and others: Let me further explain this, while Moonrise has a valid point that a better connection could be had by following his "procedure", his procedure is a different joint than that of the test conducted by Dave.Moonrise calling the weld Dave made "crap" might lead some of the less experienced members to think that a simple "T" joint with not further preparation to be an unacceptable configuration. Be assured it is quite acceptable, and a good rule of thumb is the fillet size to be equal to the thickness of the thinner parent material.  Moonrise while I do not doubt your abilities to weld or to configure a proper and strong weld joint, you argument in this instance is misguided, and misleading. Jimmy
Reply:Originally Posted by David RMore comments. The last pic in post 3 which was the second test I did with out etching the plate, I could NOT get that piece off the plate.  I needed it off so the piece would fit back in my bandsaw to do the stick test.  I could not break it off with an 8lb sledge hammer.  I put it in the vice and cranked away.  Finally I got out the carbon arc and bunt it off.  That weld was as strong as the plate.  It was done the same as the first test.  The bent plates show how strong the weld was compared to the plate.David
Reply:I think the point being debated here revolves around what one person calls "penetration to the root" vs what another does.  In many situations, fusion is all you need, but in a fillet weld, you have the opportunity to penetrate all the way to the back side of each piece.  Penetrating the entire depth of the weld joint can greatly increase the strength of the part.  It is often not necessary though.
Reply:A partial penetration weld may be acceptable for certain cases.  Most of the things I deal with it is usually not acceptable.  Incomplete penetration is not acceptable for piping, incomplete penetration is not acceptable for pressure vessels, incomplete penetration is not acceptable for welds that have to pass X-ray test, incomplete penetration from one side is not acceptable for sanitary or pharmaceautical welds, incomplete penetration is not acceptable for nuclear usage, incomplete penetration is not acceptable unless the design engineer has figured out the loads and stresses and fatigue factors and all the other 'stuff' that they are supposed to figure out when designing and analyzing things.That unwelded space between the plates is a pre-made crack.  And crack is bad.    If the material has not been turned into a homogeneous monolithic lump, then it is not as strong as it could be and you have left or introduced weakness(es) into the weldment.  I fully agree that weldments don't -always- have to be 110%.  The workmanship does or should be.  And David's fusion and visual on the weld in question was pretty darn good.  I never faulted that.But as an example of how much difference there is or can be in the strength of a weldment based on the weld penetration, take a look at the attached pics of an analysis I did of a fillet joint pretty much like David made.Both pics and models used the same materials, same loads, same dimensions, same fixturing/constraints, same weld fillet size, everything the same -except- Case 1 has the single fillet weld just fused to the plates and a 5 thou gap between the plates (pretty much like David made) and Case 2 has a complete penetration single fillet weld joining the plates.  The material is 3/8 inch thick structural plate steel (36 ksi tensile yield and 66ksi ultimate tensile strength).Case 1 has a calculated maximum stress of 117,000 psi (see picture 1 - Case1).  Which exceeds the tensile strength of the steel, right at the gap (a MAJOR stress concentration factor right there).  Look at the colored contour lines indicating the stress and see how they initiate at the crack/gap and then curve right through the middle of the plate? (see picture 2 - Case1a) Pretty much just like how David peeled the plate apart from itself.And a major cause of how and why the plate peeled away from itself is because of that 'little' gap/crack.  A stress-concentration factor.  As soon as the stress exceeds the steel's strength, the steel starts to peel away right along the greenish colored lines.  The HAZ had an effect, the slightly stronger weld bead had an effect, the possible grain in the plate from the mill had an effect, and all those things stacked together in the wrong way made the plate fail when that little gap magnified everything and the steel peeled apart.Case 2 has a calculated maximum stress of 38,000 psi (see picture 3 - Case2).  Just a little over the yield strength of the base steel.  But that localized max stress is right at the toe of the weld fillet, which is a little stronger than the A36.  All that means is that the plate and/or weld may yield and deform a -little- bit at the imposed load. Attached Images
Reply:No stone goes unturned!!Thanks Moonrise!...zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:I understand that a fully welded joint is stronger than a partially welded joint.The "complete penetration" weld joint that was sketched onto the photo of the single pass weld is a combination of a "groove weld" and "fillet weld".Unless otherwise specifed, no type of weld joint configuration, whether it be a butt groove, "T" joint, or plug weld, requires penetration beyond the point of complete fusion with the joint sidewalls and the root intersection of the joint.The single pass weld shown in the photos is a perfect fillet weld.  Both legs and the root are fully fused, and there is some "extra" penetration into the base metal which indicates the welding technique is robust enough to tolerate some variability and still be acceptably fused.  Nice weld.Extra... Extra...There may be situations were extra penetration of a weld is not desireable(beyond what is specified by the designer), since extra penetration requires extra heat input either from extra power or extra slow travel, the extra heat input can cause an extra large HAZ and extra thermal stresses with may be accompanied by extra distortion, cracking, etc.
Reply:Pulser well said.Moonreis as well point made very well.                  None of your presentation excuses your misleading statement earlier that the welds that Dave made were deficient.  Jimmy
Reply:[QUOTE]If I had a 24' X 1/2" piling I had to fillet weld end to end, how would I bevel it?How many amps and what rod (process?) do I need to get a full penetrating weld. I don't think I got big enough stuff to reach to the other side of the 3/8" plate.[/QOUTE]you could use a track burner to cut a nice bevel if thats what your getting at?as for the weld id use metal core, or dual shield just for the consistency, or just a flux core wire. with the amps cranked.6G zirconium 702 GTAW 2" xxheavy6G P.E.D. carbon steel GTAW 2" xxheavy3G titanium Gr. 2 - Gr. 7 GTAW up to 3/4" 3G 316L stainless GTAW up to 1" 3G carbon steel GTAW up to 1" 3G Hastalloy GTAW up to 3/4"1G tantalum GTAW up to .060"
Reply:i think this will settle this ordeal. try this tomorrow x 6" long cut it to show pen. and fusion. and then we will for sure see. and weld both sides.6G zirconium 702 GTAW 2" xxheavy6G P.E.D. carbon steel GTAW 2" xxheavy3G titanium Gr. 2 - Gr. 7 GTAW up to 3/4" 3G 316L stainless GTAW up to 1" 3G carbon steel GTAW up to 1" 3G Hastalloy GTAW up to 3/4"1G tantalum GTAW up to .060"
Reply:The big question here:  Will the additional heat of a full penetration weld create a larger heat affected zone and wind up weakening the joint beyond that of a joint that only has something like 60% penetration?  Your weld only needs to be stronger than your heat affected zone.A GOOD welding engineer would calculate things like that, rather than guess at it.   It's the same as an engineer that makes a table with huge legs and supports (to cover his ***), rather than calculate the loads it will withstand and where here's a huge difference in engineering and over-engineering because you can't properly engineer something.
Reply:[quote=welder155;160287]If I had a 24' X 1/2" piling I had to fillet weld end to end, how would I bevel it?How many amps and what rod (process?) do I need to get a full penetrating weld. I don't think I got big enough stuff to reach to the other side of the 3/8" plate.[/QOUTE]you could use a track burner to cut a nice bevel if thats what your getting at?as for the weld id use metal core, or dual shield just for the consistency, or just a flux core wire. with the amps cranked.
Reply:please. and your were just about spot on for the dual shield the perfect setting is 27 volts 200 amps and 300 +/- IPM haha its works amazing for me.and yes please pictures6G zirconium 702 GTAW 2" xxheavy6G P.E.D. carbon steel GTAW 2" xxheavy3G titanium Gr. 2 - Gr. 7 GTAW up to 3/4" 3G 316L stainless GTAW up to 1" 3G carbon steel GTAW up to 1" 3G Hastalloy GTAW up to 3/4"1G tantalum GTAW up to .060"
Reply:First I would like to say thanks for the demo and pics.I am not sure if I agree to the fusion is all you need for a good weld though.I believe you need both penatration and fusion together.Like worldsgreatestwelder said about 100% pen and no fusion Vs/ 50% pen and good fusion.I guess it depends on what your welding and what it's going to be doing.I read something about beveling the plates,but thats something totally differant than you was demonstrating.I meen to get a full penetation weld yes you would have to bevel the plates and either run an open root or run with a backer plate with bar stock or double bevel the vertical plate and back grind on a tee joint and run within the peramaters of the process your using to achieve the amount of penatration and fusion your looking for without compramising the HAZ.buy thats a whole nother issue. it has just been my experiance that without a good root the weld is weak.I am NOT trying to start any arguments I liked the pics,feedback and all the differant views and I think you had really good penatration on the single pass.I am just putting in my .02