What's stronger? Inside or outside corner joint welds?

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I have a job coming up that is a simple 1/4" steel L bracket with a guesset. Last time I did this the guys weren't happy they had to machine down the welds on the outside corner so it would sit flat. Had they asked me I would have done it, but they didn't. So now it's very similar just smaller. The vertical plate is about 6 or 8" and the horizontal plate is about 16" long. No idea what they are for, all I know is they are for a vehicle. The machine shop is guessing they will hold 15-20 pounds but nobody knows for sure. Somehow I doubt it since it's 1/4" steel.So they want me to weld the inside only and the gusset. I am not a fan of having things come back and rather do it right the first time around. They who do not weld seem to think the 1" or 2" gusset and an inside corner weld will be enough. Personally I am against it and I think it will look stupid with a gap sitting there between the two pieces, but what do you guys think?Here is a pic below, should I weld it like figure 1 or figure 2 if they don't want the back side welded? The original pieces were 1 piece and bent but they don't have a way to bend it and for what they are charging they want the cheapest route. They are charging peanuts for this job I think. Attached ImagesTorchmate 2x2 CNC with Flashcut CNC controlsHypertherm Powermax45 Esab ET220i Razorweld 195 MigRazorweld 200ac/dc TigTormach 770, Tormach xstechRazorweld, Vipercut/Vipermig, SSC Foot Pedal Dealer
Reply:I'd bend it.  That would be the fastest, cheapest, way.  If I had to weld, I'd go figure 1 and weld the outside solid and maybe stitch the inside at the ends and middle.ETA...   Depending on the direction and weight of the load, I may reconsider how I'd weld it.Last edited by Boostinjdm; 10-28-2014 at 02:06 AM.My name's not Jim....
Reply:w/o the direction of force known, I'd side w/ fig 1 also
Reply:I doubt welding is cheaper. It's definitely not faster. Bending is fast and cheap. What's your width? Anything under 4" wide can be bent hot with nothing more than a torch, vise, and a hammer. If your wider, figure a 2" die opening will require 15.3 tons per foot for 1/4". If it was 4" wide, for example, it would be about 5.1 tons to bend to 90. You can make a homemade die from angle iron or round bar. I made one for bending 1/2" plate from angle iron and was surprised how well it worked. Might be worth making a tool if you a several to do and if you have a press.In reality the gusset is likely carrying the majority of the load. I doubt you'd see much difference either way, inside or outside. Myself, I'd weld the inside corner leaving the outside sharp. Do it how the customer wants it. For inspiration, here are some gussets I built for a propane tank on a semi.http://weldingweb.com/vbb/showthread.php...-tank-supports
Reply:Why are you even asking here? This is obviously something you need to find out from them because it changes the dimensions of the thing...Welding/Fab Pics: www.UtahWeld.com
Reply:I agree on the bending unless they want a square tight ninety corner. Bending may give a radius to it.Welding definitely #1.
Reply:I fabricate L brackets for anchoring steel ladders frequently. If your material is only 1/4" thick, I like draw a straight line with a square, score the material 2/3 of the way through and bend it. Your score will have to be wide enough to allow the material to bend 90 degrees. Once it's bent, you can weld one pass on the inside, just like your customer wants and the outside corner will have a very nice bent radius and unwelded look to it.JasonLincoln Idealarc 250 stick/tigThermal Dynamics Cutmaster 52Miller Bobcat 250Torchmate CNC tableThermal Arc Hefty 2Ironworkers Local 720
Reply:I live all the time with people wanting some simple object made with only vague description. I build it, they say it won't work. I won't name the worst offender of all, but we sleep in the same bed.
Reply:The machine shop is asking me to do the welding (i don't work for them) so it's not my choice to bend it or not. If it was up to me I would bend it. they are ordering the material already cut. So it's cheaper for them to have me do the welding and they drill holes and pass it to the customer.The vertical piece gets bolted to the truck and weight is at the end of the horizontal piece. The far end. I believe this one is about 5" wide.I asked a few times for details and I just get the "what's the big deal, just weld it" attitudeTorchmate 2x2 CNC with Flashcut CNC controlsHypertherm Powermax45 Esab ET220i Razorweld 195 MigRazorweld 200ac/dc TigTormach 770, Tormach xstechRazorweld, Vipercut/Vipermig, SSC Foot Pedal Dealer
Reply:Maybe I'm not reading this correctly, but if I am I don't know why you can't do #1 welded inside and outside.  Outside corners are really easy to fill rounded with a bead that hardly needs ground if you run it vertical down with wire.  I wouldn't think it would have to be one long continuous bead either?
Reply:I agree with you but the don't want it. Makes zero sense to me, so if I can going to do it the way they want it I want to be sure it won't come back. So trying to see what would be the strongest way to complete this.Torchmate 2x2 CNC with Flashcut CNC controlsHypertherm Powermax45 Esab ET220i Razorweld 195 MigRazorweld 200ac/dc TigTormach 770, Tormach xstechRazorweld, Vipercut/Vipermig, SSC Foot Pedal Dealer
Reply:Why not use a piece of 2" or 2.5" x1/4" angle iron and butt weld a piece of 1/4" plate to each leg of the angle iron out to the desired length? Then add the gusset to the inside. That way there is no weld right at the corner, except for the added gusset, and it's a nice sharp corner.
Reply:Can you tig the outside? At least fuse it together without making it protrude past the edges.www.FirehouseFabricators.comZachLincoln 210mpLincoln SW200Hypertherm Powermax 45xp2x4 CNC Plasma Table.
Reply:Or go half way between 1 and 2 and weld both sides.
Reply:Originally Posted by BistineauWhy not use a piece of 2" or 2.5" x1/4" angle iron and butt weld a piece of 1/4" plate to each leg of the angle iron out to the desired length? Then add the gusset to the inside. That way there is no weld right at the corner, except for the added gusset, and it's a nice sharp corner.
Reply:Do it the way they want however I am always thinking of corrosion.  If you do not use an open corner joint and weld the joint with a fillet you leave a crack or line.  Years later moisture will work itself into the crack and it will rust stain or fail from corrosion.
Reply:im no engineer, but I see outside corner being a tensile break on the gusset welds, and then the outside corner weld breaks pretty easy. the weld becomes a hinge.inside filet would be tensile breaks on both, and in my opinion, stronger.folding the L inwards would be near impossible with the gusset, and just as strong either way.bosses stuff:trailblazer 325maxstar 200my stuff:sa 200fronius transpocket 180100 amp Lincoln w/f97 f350 DITKevin
Reply:Originally Posted by GambleThe machine shop is asking me to do the welding (i don't work for them) so it's not my choice to bend it or not. If it was up to me I would bend it. they are ordering the material already cut. So it's cheaper for them to have me do the welding and they drill holes and pass it to the customer.The vertical piece gets bolted to the truck and weight is at the end of the horizontal piece. The far end. I believe this one is about 5" wide.I asked a few times for details and I just get the "what's the big deal, just weld it" attitude
Reply:The shop wants it done a specific way. Offer no warranties, in fact insist on it and get specs in writing. Why jeopardize the business relationship with your customer by second guessing what they want, regardless of whether they know what they are doing or not? You have made them aware of the design flaws attempted to resolve it yet they want nothing of it, if you are uncomfortable, walk away. They have made it obvious that they want the work done in a specific way. If they get sued by their customer for their poor design, you have a written agreement that keeps your butt covered and your business relationship intact.  When a welder tells you to "stick it", what do they really mean?"In a time of universal deceit, telling the truth is a revolutionary act." - George Orwell
Reply:What did you ever decide to do on this project? Anything, nothing at all, turn it down, still trying to decide?
Reply:They do not have the parts ready just yet. So I will talk to them when I pick it up.Torchmate 2x2 CNC with Flashcut CNC controlsHypertherm Powermax45 Esab ET220i Razorweld 195 MigRazorweld 200ac/dc TigTormach 770, Tormach xstechRazorweld, Vipercut/Vipermig, SSC Foot Pedal Dealer
Reply:Ask'em about what I said in post 12. Maybe they will go for that. It at least eliminates weld weak spots in the corners. You know then that it has 100% steel in the 90* area, with no voids at all.
Reply:Ok working on these tonight. The scale on these things SUCK. Last time I did a job for these guys it was super clean steel. This is ****. Hit it with a flap wheel for prepDrop a bead1/4" thick, 180 amps, 3/32 red tungsten, #8 gas lens, 15cfh, 3/32 70S fillerBack side. one guy said don't weld it, the other guy said make it look pretty. So F it. Back side I welded it with 308L and ground it downGot a few more to do. I tried to setup the ProMts200 mig for this but had a hell of a time dialing it in. .035 wire, c25 gas and I couldn't get the thing to not spray transfer. Plus for whatever reason the welds were coated black. I thought the mig would burn through the mill but I guess it's pretty thick. So I did a few with the mig and one I did 2 passes and it looks awesome. But I couldn't find tune it for how I wanted it and felt I was wasting too much time so I just fired up the tig. Also mig welding around the gusset (no pic) looked bad. Even the tig welds around the gusset didn't look good because of all the mill. My flap wheel is now coated black and pretty useless. So almost done, 3 more to do after I'm done relaxing then onto a fun aluminum turbo project for a guy that won't take very long at all.Now for the quiz. Can anyone tell me why I decided to use 308L on the back side?Torchmate 2x2 CNC with Flashcut CNC controlsHypertherm Powermax45 Esab ET220i Razorweld 195 MigRazorweld 200ac/dc TigTormach 770, Tormach xstechRazorweld, Vipercut/Vipermig, SSC Foot Pedal Dealer
Reply:Originally Posted by GambleNow for the quiz. Can anyone tell me why I decided to use 308L on the back side?