What is the prefered corner treatment

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I am designing a large stand made out of 2" x 2" x 11 gauge steel tubing. I have designed most of the corners so that two of the members are 90 deg miters and the third member just butts up to the side of the mitered members.Not being familiar with welding, I choose this method for "looks" and seemed easier sitting here at my desk.The other method would be to have one member that the other two members would butt up to the side of. The first member would still be open at the end and would require a cap.My question is, as a welder, which method would you prefer to cut and weld?1) Several mitered cuts and no capsor2) All straight cuts and several caps?
Reply:I have added a picture in case my wording is hard to follow. Attached Images
Reply:Technically, for a small assembly I don't think it really makes any difference which method you choose.  This is one of the reasons I like working in steel versus wood.So it becomes a matter of choice, and perhaps skill.  How accurate can you cut the miters?  How easy is it for you to cut the square caps?Of course, either way you can grind the welds all flat with the material and no one will be able to tell how it was put together.    -MondoMember, AWSLincoln ProMIG 140Lincoln AC TombstoneCraftsman Lathe 12 x 24 c1935Atlas MFC Horizontal MillCraftsman Commercial Lathe 12 x 36 c1970- - - I'll just keep on keepin' on.
Reply:Straight cuts will be faster, especially if you can use plastic end-caps that pop into place.  Welding end caps on is easy with TIG; you don't need to add filler...I think mitred corners look better, but they are a PITA to cut correctly without a jig of some kind.Benson's Mobile Welding - Dayton, OH metro area - AWS Certified Welding Inspector
Reply:I like the miter cut because you don’t have to fool around with a cap for the open end of a 90 deg. joint especially if welds need to ground flush.A miter joint is less welding than a 90 deg. joint with a cap.To make a miter joint you need a good precise saw. Also a miter joint makes it more difficult to keep dimensions accurate, especially if you use a gap (root) style joint fit up.Sure does look better too, but may not be worth the effort if the project doesn’t call for it. I am a firm believer in the KISS method. “Keep It Simple Stupid”. It works for me.Good luck with your project. Maybe post some pics.
Reply:I use straight cuts almost exclusively.  It just keeps me from changing the saw position and faster on the cutting end.  As for capping I use metal squares smaller the the OD of the tubing.  I also leave the open end of the tubing recess so when I add the cap it sit flush. Choose the cap smaller so you can grind  and shape the weld without grinding the weld away.For a decorative look you can actually leave it raised and shape the metal cap.
Reply:FWIW-- I almost always do a regular ol' 90.  Easier, and most of my stuff doesn't have to be real pretty.  I usually leave the weld as is without grinding it flush.  I figure that little bit of filler is some extra insurance(unless it has to be ground to fit something that butts to it).  Maybe wrong, but it's what I do.Caps are fairly easy to make.  Measure for a size that allows the cap enough meat to sit on top of the end of the tubing with enough room for filler.  3x3 3/16 wall square tubing gets a 2 3/4 x 2 3/4 square cap for me anyway.  Go low amps DC- on the rod, and it shouldn't blow thru, and it grinds pretty easy if you don't go wild with the filler.  Either way, I really hate caps, but it keeps crud outta the tubing, and it also gives strength to the tubing specially if the cap is near where you have another piece welded on.  It prevents it from deforming under load.  Like the design you've pictured.I ramble.  Sorry"Any day above ground is a good day"http://www.farmersamm.com/
Reply:Raised cap, not recessed inside tubing.Sufficient shoulder so that butt weld travels all around all 4 sides of the welded joint.  I like to leave a minimum 3/8 shoulder stickin' out (this one is a little larger than 3/8).  I don't like the flush butt joints on a corner.  I feel it's a little bit stronger the way I do it.  I'm sure lots of people do it different.Oh, and if you do a raised cap, make your fitup measurements/markings before you weld the cap on.  Sometimes they aren't always perfect, and can mess up your measurements. Attached Images"Any day above ground is a good day"http://www.farmersamm.com/
Reply:Boy Howdy, I sure beat that to death"Any day above ground is a good day"http://www.farmersamm.com/
Reply:Look here, I used bothhttp://weldingweb.com/vbb/showthread.php...ighlight=cableDavidReal world weldin.  When I grow up I want to be a tig weldor.
Reply:Ramblin' Samm:Ain't nothin' wrong with ramblin'. It's just a lil overthinkin', and that gives more information to the question. I just filter out what don't interest me. In this case, I'd square cut and cap, cause it's easier for me than 45's. And I have a TIG, so it's easy to cap 'prettily'. 9-11-2001......We Will Never ForgetRetired desk jockey. Hobby weldor with a little training. Craftsman O/A---Flat, Vert, Ovhd, Horz. Miller Syncrowave 250
Reply:I almost always do the miter cut.  Less welding.  I also have 2 saws, one exclusively for the miter cuts. and a large welding table for clamping in position.  I've done so much of it over the years that if I can't clamp it, I will position it out of square and allow the inside corner weld to pull it back in square from weld shrinkage (cooling) prior to completing all welds.If I were just starting out, or, needed a new saw, here's the one I'd buy.  Made by Ellis Mfg. in Verona, WI.  It's their Model 1600  Mitre (their spelling) Saw.  Neat rig.  Material does not change postion for straight to miter cuts, the saw head pivots.  I looked one over that someone here in Central PA bought.  Well made.  I buy ALL my band saw blades from Ellis.  I especially like the Bi-Metal vari-tooth blades.  Last a long time.  Here's a link to their web site.http://www.ellissaw.com/
Reply:In general, I will use the square cut. Simple, and easier to keep it all square.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:I personally use both, but that isn't a problem with a 90 degree bessey jig.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:2 45 degree cuts on each piece and triple miter the corner.but thats not the easiest wayinsert thoughtful quote from someone else2000 Thermal Arc 300GTSW 3.5 hours1946 Monarch 20 x 54 Lathe1998 Supermax 10x54 Mill2004 Haco Atlantic 1/2" Capacity Lasernot mine but i get to play with it
Reply:Thanks for all the great advice.Looks like if you have the right equipment, it really doesn't matter.Since I am not a welder, I wanted to make sure I didn't ask for something stupid.Here is a drawing of what I am trying to get built. Attached Images
Reply:Definitely butt joints, no miter, except the diagonal braces.  That way all your measurements for the cross pieces will be the same. You will save time and money.  Always good to have a picture.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:cgroh1,Looks like a well designed portable platform. I can tell much thought was put into your project. I have made a few safety maintenance platforms for industry and that is why I thought I’d elaborate a bit.In my situation, once the design is drawn up, I have to send the paperwork to an engineering service that will have a Professional Engineer evaluate and finalize material selection, alloy, welding procedures, hand railing systems and component parts to satisfy OSHA specifications for such platforms.It can be a long drawn out process and very expensive. I have to hire this service because I am not a Certified Design Engineer. My product and liability insurance states that they will not assume responsibility otherwise.Hopefully your situation is different than mine but nowadays unfortunately, you have to protect yourself from lawsuits of all kinds.Look forward to seeing some pictures of the finished product.
Reply:with miter cuts I could see welding becoming an issue. With the tubing cut to 45's you wouldn't be able to tack it all together and still be able to wrap the entire seem. You would have to weld the 45 inside before you put another piece of tubing over it. That would take a lot more time than straight cuts because you could just tack it all together, check your measurements and then weld it up, while still being able to fuse the entire seem and all the tubing together.I hope that made sense.
Reply:If I miter the corners and then grind it flush, It has cracked on me.  If I leave the weld it has not.Miters look better square corners are probably stronger.  I love working with square tubing.On something like that, I would cap all visible open ends.David.Real world weldin.  When I grow up I want to be a tig weldor.
Reply:Why not miter the top rail and then butt the leg???
Reply:Originally Posted by chenry2 45 degree cuts on each piece and triple miter the corner.but thats not the easiest way
Reply:Caps should be the same as the wall thickness of the tube.  I agree 100% with above, make the caps square so they don't drop in the tube.   A fillet is much better than a butt weld.David Real world weldin.  When I grow up I want to be a tig weldor.