grain structure of steel plate?

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I need to make a special size angle, 1-3/4" x 3" x 1/4" and it needs be 24" long. I've tried bending flat stock before, with the grain, and it cracked at the bend before it got to 90*. Before i go and cut the blank out of a piece of plate, do i need to worry about grain direction of the plate, or does  plate even have a grain direction? If so, how do i find it?John 3:16(2) Miller Pheonix 456(2) Millermertic 252Dynasty 210DXHobart 210MVPDoringer D350 SA Cold SawScotchman 350LT Cold SawWebb 10x50 MillWebb 15x40 LatheGeka Bendicrop Ironworker
Reply:EcondronUnless a sharp heel is prohibitive, consider ripping the surplus off of an angle-iron with a vertical band-saw  -  short work.Opus
Reply:Yes metal has a grain direction, it's in the direction it was rolled at the mill, but I second what opus said - grab some angle, and cut it down - fast and easy Dave J.Beware of false knowledge; it is more dangerous than ignorance. ~George Bernard Shaw~ Syncro 350Invertec v250-sThermal Arc 161 and 300MM210DialarcTried being normal once, didn't take....I think it was a Tuesday.
Reply:That's what I've been doing. The Angle is being used in a high traffic area and the customer likes the idea of a rounded back edge. I know you can get radius edge angle, but i think forming the angle will be the most cost effective method. I should also mention i Need to make 28 of these. So I'll pay a little more and order them pre cut to size and just bend them and save the labor on band sawing them and cleaning the rough edges. I guess i would just need to order them with a specified grain direction?
Reply:You must have an impressive forming capability.  Hard to envision more cost in sawing and relieving edges with a grinder than in forming 24+ feet of flat stock.Jerry30+ yrs Army Infantry & Field Artillery, 25 yrs agoMiller 350LX Tig Runner TA 210, spool gunLincoln 250/250 IdealArcESAB PCM 500i PlasmaKazoo 30"  vert BSKazoo 9x16 horiz BSClausing 12x24 lathe20T Air Press
Reply:Can't you just outsource it to a shop with a brake?
Reply:A36 Plate can be bent without cracking but you have to stay within some limits. A hard 90 likely isn't going to happen. You'll have an inside and outside radius. Normally, to air brake 1/4" plate you would use a die 8 x thickness. The inside radius is typically 5/32 of the die opening. With a 1.5" die your inside radius is just under the plate thickness and the outside radius would be just under a half inch.If the radius is ok then any press shop could whip these out. I did a quick render so you can see what I'm talking about.
Reply:Cannot believe the plate broke, nevermind the grain direction.Something else must've happened there.When using regular steel, 1/4" plate should bend like butter.
Reply:That's a good point, I'll just see about ordering them already bent.And Kingnero, I saw it happen. Maybe the die size was not appropriate for the plate? And it was hot dipped galvanized so it was stress relieved.John 3:16(2) Miller Pheonix 456(2) Millermertic 252Dynasty 210DXHobart 210MVPDoringer D350 SA Cold SawScotchman 350LT Cold SawWebb 10x50 MillWebb 15x40 LatheGeka Bendicrop Ironworker
Reply:As forhire said you need the correct radius first then bent on the correct press.I have seen that happen many times threw the years also have seen steel delaminate from impurites in the metal when bent.
Reply:didn't question that it happened, merely pointing out that it really shouldn't have happened. If the plate broke, something else was wrong. Die size/radius, most likely, impurities in today's steel really are exceptions when you order from european steel mills (china steel is a whole 'nother thing).also, HDG and stress relieving - I don't really see the connection? temps for HDG aren't in the correct scale for stress relieving.
Reply:Yeah you're right. 850* of the galvanizing bath is enough to take out some of the peak stresses, but the bar by no means would be considered "stress relieved". I had that piece bent at my local shop and they're the ones that told me it was stress relieved and broke the piece. Well now you all got me thinking. Because 3" x 1-1/2" angle will work, so I can technically use 4-1/2" flat stock. So you're saying if I use the correct radius die, a piece of A36 flat stock (this one won't be galvanized) shouldn't crack at all and that the shop who did the original bending did something wrong?John 3:16(2) Miller Pheonix 456(2) Millermertic 252Dynasty 210DXHobart 210MVPDoringer D350 SA Cold SawScotchman 350LT Cold SawWebb 10x50 MillWebb 15x40 LatheGeka Bendicrop Ironworker
Reply:One more thing to remember, on 1/4" thickness material the anvil nose radius should be 1 x thickness. A sharp or flat nosed anvil will stress the bend more than it should. It takes time to change dies. Make sure your shop isn't lazy.
Reply:Hello Econdron, flat bar is one of the worst types of material to try to bend lengthwise. It's similar to applying a load to a 2X4, if you apply it with the ends supported it will fair well, if you apply a load with the edges supported it will tend to split. That flat bar is no different. The other thing that is against you here is the cooling rate of the flat bar from it's manufacture. It is rolled/shaped from a much larger piece of stock and once it has reached size it cools rapidly and even though it technically shouldn't have enough carbon to cause it to fracture easily, it will, compared to material that has been sheared from a master sheet with a slower cool time, for instance. Considering grain is something that can work in your favor and if you are having the pieces sheared you can specify the grain direction and this will be to your benefit, might also cost you a bit more though. Correct punch and die sizing will prevent a lot of the cracking issues, yet you would also have to determine flat layouts much more closely if the end sizes are important. Just a bit more to add to the information that has already been shared. Good luck and best regards, Allanaevald
Reply:FWIW, hot dip galvanizing (800*F) isn't going to do much stress relieving in the parent metal, to say the least.  There was something else definitely wrong with the cracking issues as described originally by the OP.Lincoln Power Mig 216Lincoln AC/DC-225/125Miller  625 X-Treme PlasmaMiller 211 Forney 95FI-A 301HF 91110Victor Journeyman O/PMilwaukee DaytonMakita  Baileigh NRA Life Member
Reply:I like my old welding books from the 50's by Lincoln Electric and Linde.  They tell you about the bending direction and things like that.  It's nice when you can buy an old used book delivered for maybe $6. Got the Lincoln book at a thrift store for 50 cents."USMCPOP" First-born son: KIA  Iraq 1/26/05Syncrowave 250 w/ Coolmate 3Dialarc 250, Idealarc 250SP-175 +Firepower TIG 160S (gave the TA 161 STL to the son)Lincwelder AC180C (1952)Victor & Smith O/A torchesMiller spot welder
Reply:Alright, I brought some plate to another shop to have bent. I informed them about what happened last time, and they said the same thing you all said. Shouldn't have broke, they must have used too small of a die, etc. Then I get a call 20 minutes later saying they tried bending it and it cracked, just like the last one. Have any of you successfully bent flat stock along the grain?John 3:16(2) Miller Pheonix 456(2) Millermertic 252Dynasty 210DXHobart 210MVPDoringer D350 SA Cold SawScotchman 350LT Cold SawWebb 10x50 MillWebb 15x40 LatheGeka Bendicrop Ironworker
Reply:Try a different shop. A few weldersA lot of hammersA whole lot of C-clamps