Angle Iron cutting

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I'm 53 and just decided to buy a welder and learn to weld again; I did some stick welding in high school but that was a long time ago. I bought a Lincoln Pro Mig 180 at Lowes and have been practicing on some scrap.  I have a few repair jobs I want to do, but first I want to take some angle iron and build a welding cart and I have a few questions;1. I've read some of the forum posts, but I'm still not clear on the different ways to cut angle iron so that it fits together well.  Are there some diagrams or detailed instructions, with pictures if possible, here?2. I bought some Dewalt cut off wheels or my Bosch 4" grinder that seem to be working OK.  I also bought some Dewalt cutting wheels for my Skill Saw.  Is a Skill Saw ok to cut with?  What's the best cutting wheel to buy and who from? 3. Is there anything like a Mitre box for angle iron?4. What type Square for the angles?Thanks;  Steve
Reply:The easiest and least expensive way is to set an abrasive chop saw at 45 deg and make the cuts. They are not super accurate so you'll probably need to play with the setting a bit and make some adjustments and expect to have to fill some gaps. They do make special cold cut carbide saws with better miter systems and band saws that will cut more accurately, but the price goes up. It is possible to use a hack saw in a standard cheap miter box. But thats the hard way to do it. Note: a standard wood miter saw ( ie chop saw) with an abrasive blade will  not stand up to the abrasive dust and sparks for long. If you want to kill the saw cut steel with it. The second way is to cope the corner where you notch the one piece to fit the second. (see pict below) This takes more time, but you can get a better fit and it's a bit more forgiving on less than perfect cuts.A standard circular saw (skill saw) isn't the greatest choice to cut angle. You could, but the cut wont be all that accurate and you'll have issues with fit up. Also many of the cheap saws won't stand up to the grit and sparks. I use my worm drive to cut sheet on occasions. It's robust enough to take the beating and survive for a longer length of time. I expect to kill the saw at some point however from the abuse it takes.I suggest you go with quality wheels and blades. Dewalt & Norton, among others make a good blades. I'd avoid ones from HF. Also don't get them wet ( like dripping wet) Even after drying the binder has been damaged and they will fly apart with no warning. NOT a fun time. I have the utmost respect for slitting disks, grinding wheels and such. If I'm doing a lot I wear leathers, full face shield and safety glasses. I've had my share go BANG and get nailed by the shrapnel. I also always make sure my face is on the motor side of the grinder and never in line with the blade.As far as a square. I use a few. I have a standard 24" framing square that I use for set up, and a couple small 6" speedy squares ( the alum ones not the plastic cheepies) as well as one of the large adjustable angle ones and a 12" speedy square. On occasion I'll use my machinist square for layout. I have a 1/2 dozen or so magnet squares, but I almost never use them except to help hold things roughly in position say to take measurements. I just tack one corner and then use the square to set the corner and tack the rest adjusting as needed. Attached Images.No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:When i have to cut 45's on the chop saw, I find it's more accurate to just cut 90's with the chop saw, then mark off 45 degrees at the ends with a speed square and slice off the ends with an angle grinder with a zip cut wheel.  The chop saw never cuts an accurate 45.  When I slice the corner off with the angle grinder, I start the cut at the inside wall instead of the outside wall, leaving the one leg of the angle un-cut at the edge and just slice off the face of other leg.  This leaves a nice 90* groove gap for the outside corner weld to fill in and is also quicker-easier to cut.  The end 90* gap allows the outside corner weld to lay in instead of humping up, needing subsequent grinding off.   Leaving that end edge un-cut with the zip wheel eliminates grinding that bevel for the outside corner.  Then the only bevel to grind is the face of the 45* leg so that weld will lay in flat and fully penetrate.MM350P/Python/Q300MM175/Q300DialarcHFHTP MIG200PowCon300SMHypertherm380ThermalArc185Purox oaF350CrewCab4x4LoadNGo utilitybedBobcat250XMT304/Optima/SpoolmaticSuitcase12RC/Q300Suitcase8RC/Q400Passport/Q300Smith op
Reply:weldome to weldingweb, you will get many opinions here..i cant say i never use a thinwheel, but i believe they are inherently dangerous.. i'd suggest you buy a nice portaband..you'll never regret it.....
Reply:44.5 degrees will make your corners look better. I learned that from a guy that made picture frames.
Reply:I usually cope my angle iron.  I typically set the inside edges together so I weld in the vee on the outside.  After welding shape with a grinder.    Since I cut them using band saw or portaband, I don't bother radius the corner of the coped, I just cut an small angle to compensate for the radius of inside the receiving angle iron.    If the inside edges are together, then the edges you must remember to subtract the 2x the thickness of your notched angle from the receiving angle iron for final lenght.  Note with coped angle, the intermediate supports can be cut identical to the ends. The receiving angle iron remains uncut.Also, with large parts, your saw capacity might become an issue if you cut 45 degrees.
Reply:Thanks for all the replys.  The picture from DSW is how I've been doing my practice ones, although they don't look nearly as neat.  Although I've had pretty good luck so far with the 4" grinder and a cutting wheel, I may buy a portaband. The Skill Saw hasn't worked very well and my experience so far lines up with the comments made here.  Thanks again, I'll have plenty of questions.
Reply:Steve,I have the same welder as you and also am having lots of fun with it. Nice machine.While I agree that setting up my abrasive wheel saw takes a bit of time, I use a 45-degree square to make sure it is right and then I can cut any number of 45's that I need to. I try to cut as many of the 45's that I need for the job at once to make better use of the time and that does make it a faster process. for the one-offs, I have an angle grinder that I leave set up with a cutting disk.If it would help, I have reviews of "our" welder and a couple ab rasive wheel saws at the link below.ReviewsTom Hintz, publisherwww.newmetalworker.comLincoln Pro Mig 180Lincoln AC 255Determination
Reply:I very seldom cut angle iron at 45's anymore.  I almost always cope the ends and I do most of it with a jig saw sporting a good quality metal blade. It's the cheapest, easiest, and most acurate way I've found to do it.StephenMillermatic 251Miller Syncrowave 200Miller 30A SpoolgunHypertherm Powermax 30Etc., etc., etc.............Cancer Sucks!
Reply:Originally Posted by DesertRider33When i have to cut 45's on the chop saw, I find it's more accurate to just cut 90's with the chop saw, then mark off 45 degrees at the ends with a speed square and slice off the ends with an angle grinder with a zip cut wheel.  The chop saw never cuts an accurate 45.  When I slice the corner off with the angle grinder, I start the cut at the inside wall instead of the outside wall, leaving the one leg of the angle un-cut at the edge and just slice off the face of other leg.  This leaves a nice 90* groove gap for the outside corner weld to fill in and is also quicker-easier to cut.  The end 90* gap allows the outside corner weld to lay in instead of humping up, needing subsequent grinding off.   Leaving that end edge un-cut with the zip wheel eliminates grinding that bevel for the outside corner.  Then the only bevel to grind is the face of the 45* leg so that weld will lay in flat and fully penetrate.
Reply:Thanks for the post Tom; I'm out in my shop now and have just finished practicing a few angle iron cuts and welds.  For the most part, the welding is coming along ok, its the cutting and fitting that's the problem now.  Looks like I'm going to have to buy another bottle though, that gas is going fast on the MIG stuff.  Steve
Reply:Originally Posted by Scott YoungOn thin stuff I do your method here.  most of the time I use O/A.  It is just faster and very accurate.  When I was in the field, all we had was a portaband and O/A.  I did eventually start taking a chop saw for simple 90s and then coped with zip wheel or O/A.  With a 00 tip you can slice and dice faster than any method.  I run two cutting heads one with 00 and one with a number 1.  I have a straight and 45 head that has scarfing tips on it, but with the first two I can cut and cope all day faster than I can set it in a saw.  Often the material is too big to manuever into a saw easily in the field.  I treat working at home much like working in the field due to not having over heads and long roller racks.
Reply:Originally Posted by stevenstiltsThanks for the post Tom; I'm out in my shop now and have just finished practicing a few angle iron cuts and welds.  For the most part, the welding is coming along ok, its the cutting and fitting that's the problem now.  Looks like I'm going to have to buy another bottle though, that gas is going fast on the MIG stuff.  Steve
Reply:I might try that today. I already turned it down below what's recommend in the Lincoln manual for the welder and I don't notice any difference.Lincoln Pro Mig 180Everlast PowerARC 200
Reply:it all depends on the tools you have at handi go with miter because i have a good saw Attached Images
Reply:That's a pretty nice setup there. I'm not looking to spend too much more myself because I'm just a hobby welder rather than a professional. The coping method will probably work well enough for me right now. Of course as I look at your pictures I see some of the angles are not 45s. Then I guess the mitre would be the best choice.Lincoln Pro Mig 180Everlast PowerARC 200