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tsmartin_98
03-17-2011, 08:06 PM
The latest e-mail tip shows using an inverted stub of angle iron to clamp a piece of similar sized angle in a vise when wanting to cut through the leg portion. I must, respectfully disagree with this method. I've never seen angle iron with perfectly square leg edges. They are usually rounded to some degree from the rolling process. When you have 2 rounded edges facing each other they tend to slide past one another when pressure is applied. Ask me how I know.

A safer way is to use a piece of square or rectangular tubing to span the bottom leg and apply the clamping force directly to the backside of the angle iron and vise jaw.

TS

Carld
03-17-2011, 08:18 PM
Opps, I deleted it without looking so now I am not sure of what it showed. From what you have described I agree with you. Angle iron is kind of tricky to cut sometimes. I always put it in the saw as an upside down V. That's with the point of the V up.

If I want to cut one leg I do what you do.

Silverback
03-19-2011, 08:00 PM
I've seen that same advice someplace else before, never understood where it came from...

First, like you point out, they're rarely really square and typically have rounded edges so I don't see how it wouldn't be a frustrating experience in a lot of cases just to get it to stay.

Second, you should generally cut angle iron with the angle side up so you have the greatest number of teeth engaged at a time... just be careful when you start the cut because if you just drop the blade on the point of the angle you could strip some teeth off of it. That way usually both cuts well and isn't a hassle at all to clamp in that position either.

MichaelP
03-19-2011, 11:01 PM
Last two tips disseminated by e-mail could've been better, IMHO. The first one informs us that a sharp blade on a hacksaw is better than a dull one, and that a lubrication helps. I suppose, the tip must be a revelation for us. And now this...

Looks like there is a shortage of good tips and abundance of those who desperately want to be published.

Maybe I'm a bit too cranky nowadays, however.;)

David Powell
03-20-2011, 07:51 AM
I am sure the posters wished to help, but maybe their posts were a little off the mark, DUE TO THEIR EXPERIENCES IN ACTUALLY TRYING TO CUT ANGLE IRON. The thing I find frustrating is that I often want to cut just one leg to leave the other untouched by the saw then I leave just one mark right across the remaining leg either with hacksaw or worse and usually deeper, bandsaw. Ok I know slow down slow down, cut, look cut again, will get me there but hell lifes too short and i want my one legged end of angle iron NOW to make that angle iron tool to do the job I should have finished yesterday! Any hints here folks David Powell.

Toolguy
03-20-2011, 10:31 AM
Put a layer or two of masking tape on the leg you don't want to cut. When the blade hits the tape, stop cutting. Peel tape off and go to the next step.

metalmagpie
03-20-2011, 11:22 AM
Yes, short pieces of malformed angle iron have limited value as clamping aids. However, there is plenty of correctly formed angle iron in this world, and I have a small bucket full of 1-3" clips of various sizes of angle and flat stock which I use in clamping.

It kind of depends on clamping angle for what .. lots of times when fitting material for a weldment, perfect alignment isn't necessary.

There are two ways to cut angle ends for a 90 joint. One is to cope both pieces at 45, and the other is to leave one end straight and notch the other to fit it. I have cut notched joints like this countless hundreds of times (I once fitted angle iron floor grating supports for 3 years building Navy ships) and can say a couple things. The fastest way to notch like that is with an ironworker with a notching attachment. Next fastest way is with a cutting torch. I have done many notches with a bandsaw, though, and I cut the leg sticking straight up until it just starts to cut sideways on the lower leg and then lift the saw up. Then you have to feed the angle in from the end to a vertical bandsaw blade to make the other cut to complete the notch. Any residual imperfections can easily be fixed when welding.

Don't try to cut to close to length, and don't try to cut the notch perfectly to size. Leave little gaps. Learn to deal with distortion when you fit up and tack.

metalmagpie

Paul Alciatore
03-20-2011, 04:47 PM
I read the tip. It showed two pieces or angle iron in a box arrangement and the idea was to make cutting just one side easier.

It may fail with rounded edges on much of the HRS angle out there. Would work better with most CRS and defenitely better on extruded aluminum angle which has much better edges.

One would assume that if you wanted to cut just one side, you would also be making a length-wise cut to remove the side up to that cut and that length-wise cut would be the more challenging one. If you were doing this, the one side could be cut with the open side of the angle against one jaw and just stop when the cut reaches the apex. The angle at the bottom of the cut would be eliminated by the length-wise cut. It may be better to do the length-wise cut first.

Another help would be to do it the way suggested, but use an additional flat scrap, about as thick as the web of the angle, UNDER the bottom piece of angle to hold it up and away from the rounded edge of the piece being cut. Or use a few small washers or nuts or whatever to get this spacing - it would not be critical.

MichaelP
03-20-2011, 05:20 PM
How about just a simple square block to hold the angle? :)

Silverback
04-22-2011, 01:52 PM
Put a layer or two of masking tape on the leg you don't want to cut. When the blade hits the tape, stop cutting. Peel tape off and go to the next step.

Make sure that the angle end is toward the pivot of the saw, that end gets cut slightly faster then the other so by the time you see a mark on the tape you know that is entirely through. for that matter, you don't really have to get all the way down to the tape, since the curf of the blade will make up for being a little short

Silverback
04-22-2011, 01:55 PM
I read the tip. It showed two pieces or angle iron in a box arrangement and the idea was to make cutting just one side easier.

It may fail with rounded edges on much of the HRS angle out there. Would work better with most CRS and defenitely better on extruded aluminum angle which has much better edges.

One would assume that if you wanted to cut just one side, you would also be making a length-wise cut to remove the side up to that cut and that length-wise cut would be the more challenging one. If you were doing this, the one side could be cut with the open side of the angle against one jaw and just stop when the cut reaches the apex. The angle at the bottom of the cut would be eliminated by the length-wise cut. It may be better to do the length-wise cut first.

Another help would be to do it the way suggested, but use an additional flat scrap, about as thick as the web of the angle, UNDER the bottom piece of angle to hold it up and away from the rounded edge of the piece being cut. Or use a few small washers or nuts or whatever to get this spacing - it would not be critical.

if I need to do that kind of thing I grab a scrap of 2x lumber and put the angle over it. The rounded edges typically fit the rounded inside of the angle (if not a pass or 2 with a knife, plane or saw will take off enough that it will) and it will support the piece, then just get one of the legs of the angle between the 2x and the saw vice jaw and you're good.

boslab
04-22-2011, 08:52 PM
RSA [rolled steel angle] in not supposed to be square, the radii are deliberate to reduce stress raisers and stop cracking.
Ther is a breed of square angle called bright mild steel drawn, comparitivly weak stuff, prone to crack if bent.
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