And the hits just keep on comin'!!!

[farmersamm]

If I ever get this GODDAMN BRACKET done it's gonna be a miracle.

This is one that was cut apart to redo because of arc blow problems. N0T THE ONE IN A PREVIOUS POST.

Cut it apart, ground off the weld on the machined part, cut a new piece of plate to weld it to. Clamped it to another piece of flat, welded, AND THE GODDAMN METAL CRACKED. NOT THE WELD...........THE METAL

IT CRACKED PERFECTLY, LIKE IT HAD BEEN CUT OR MACHINED

Has ANYBODY ever had this happen???????????????????

One cracked immediately after being welded, and the other cracked with a few good whacks with a hammer

$%$$##$@!*&^%$@#%

[farmersamm]

Looks like it's been cut with a stinkin' acetylene torch

[Supe]

I'm guessing there was no preheat, and that steel probably has a higher carbon content than you thought.

[Oldiron2]

If those last two pictures show the 'cracked edge', I'd guess the piece you used already had the cut in it and somebody had once welded it together just on the surface, getting no penetration at all. The surface would have no fumes or rust deposited on it if the crack hadn't been pre-existing. Or tool marks!

[DesertRider33]

Originally Posted by Oldiron2

If those last two pictures show the 'cracked edge', I'd guess the piece you used already had the cut in it and somebody had once welded it together just on the surface, getting no penetration at all. The surface would have no fumes or rust deposited on it if the crack hadn't been pre-existing. Or tool marks!

I agree, that could not have been a solid piece of metal before Samm welded it. Even the surface of the crack doesn't look anything like a cracked piece of metal. It does indeed look like it had been cut before.

[farmersamm]

Craziest thing I ever saw.

I'll take a pic later of how it was supposed to be, and how it was clamped. As far as I can tell, there was no restraint on the joint where it cracked.

I'm so pissed off that I locked everything up, and I'm gonna take the rest of the day to sit in the sun sippin' suds and contemplate my problems

[Burnit]

Originally Posted by farmersamm

I'm gonna take the rest of the day to sit in the sun sippin' suds and contemplate my problems

Just make sure you don't contemplate a whole case of problems

[Ken Dennis]

Oh hell Samm!
Superglue it.

[DesertRider33]

Bevel it out and do a beveled fillet on both sides. Full penetration should hold it on there.

[MoonRise]

Those pieces with the holes in them were welded as fillet welds to the long plate?

As mentioned, they were sometime previously cut apart and barely welded back together. As evidenced by the machine marks and rust and such on them on the 'inside'.

DR33, he needs to bevel them out and do a GROOVE weld (butt weld) to put the mounting lug ears back together with the pieces still welded (via fillet welds ) to the flate plate. If he removes the still attached pieces from the flat plate and then puts the beveled lugs/ears onto the flate plate, then he is doing fillet welds.

Samm,

Whack the pieces with a big hammer before going further, just to make sure there are no other 'surprises' in the steel pieces. Let out some of your anger and frustration. Wear eye and ear protection though.

[lugweld]

Samm.

Whoever machined this part for you is resposible for that...unless you "machined" it for yourself. I think what happened, by the way it looks, someone ran out of material and welded it together and ground it smooth to make a single piece. And from the looks of it, they put a partime high school student on it to get some training.

Now, it either that or at the factory, someone welded it together to complete a short piece on the end of the day.

Very interesting....Are you sure you weren't using "beer" vision when you were doing that and did it with out remembering?

BTW, that looks like a plasma cut.

[DesertRider33]

Provided a short decrease in the length of the bracket ears won't create a problem with whatever they mount to or support, I would grind all that muck off the flat plate (or just start with a fresh piece of flat plate and recycle that one), bevel both sides of each bracket and do a beveled fillet on each side of each bracket. You really don't know what all is underneath all those welds on the flat plate. Doing a butt weld to that mess might result in another failure some time down the road.

[farmersamm]

The sun was great, the beer was even GREATER

Took some pics of how the thing was meant to be, and how it was clamped while welding. Everything is exactly as it was. I even put the damn metal back on to the place it cracked. Perfect fit.

Never experienced this in over 12yrs. of making stuff. It might be a function of the increased tensile strength of the 7018. Always used 6013 until recently.

The parts with the machined holes were cleaned up after cutting the original weldment apart. They're the only thing left from the original thing. The long piece of plate is new.

Standard A-36 mild steel.

Uprights...1/2" plate

Long piece...3/8 plate

Piece that it's/was clamped to..... 1/2 plate

The only thing that I can figure that by restricting the movement of the base plate, the stress had nowhere to go but into the upright pieces with the holes in 'em. But the clamping should not have restricted movement that much. It was, after all, just clamped to a piece of plate. The plate should have moved.

About preheat. It's a pretty small mass. And there were a series of welds all done at different places(12 in all, it's a built up weld). No welds were done back to back. I skipped around in order to let stuff cool. And the interpass heat shouldn't have made pre/post heat unecessary. Or maybe not

Somethin' for the X Files

[farmersamm]

When originally cut apart I used the OA to get rid of the welds. Could I have made a weird HAZ??

Mild steel supposedly doesn't have a HAZ (I think??)

[lugweld]

Samm,

That absolutely was some sort of mechanically made cut and re weld, then grind job. Nothing else. If you paid someone for that then go get yo' money.

[farmersamm]

When I cut apart the original weldment I didn't use water to cool it, it just cooled down in air. Had lunch at the time, then came back to grind off what was left of the welds after gouging them with the torch

This is F'n weird

[farmersamm]

Lugweld--- I'm the machine shop. The machining was limited to boring the hole. Had nothing to do with the edge that cracked. Look at the original pics, it cracked exactly above where it was welded, and in a perfect line

[farmersamm]

What's left on the flat plate is part of the upright ears. Exactly the height of the weld

[DesertRider33]

This is my theory-

It looks to me that because the welds holding the brackets to themselves where they had been previously cut were so small, when the welds you put in cooled and tried to 'pull' the brackets toward the plate in both directions, those skinny welds broke.

[DesertRider33]

What we're all tryin to say Samm, is that 'crack' is not a straight-through crack like you think it is. Look at the surface of it. No crack comes out that straight, flat and even, all throughout it's length and depth, on two seperate pieces of metal, no less. It's a cut, that was welded together with practicaly no penetration, and cracked through the skinny welds holding the cut pieces together.

[DesertRider33]

You will probly see this much clearer tomorrow after the beer is gone....

[David R]

DR33, I'm with you on all counts!






Thats 3 six packs But I lost count after a "few in the sun"

[farmersamm]

BULLSH!T

Didn't just fall offa a beet truck from Boise

These are closeups taken within 1 inch of the fracture. Hell, I know what I'm seein' but I want to know why it happened. The break is absolutely perfect

[David R]

If it were a break, it would look crystallized.

I had beets with my dinner.

David

[jrw159]

Farmersamm,
I am going to step out on the limb and take a shot at this. What it appears happened, IMHO, is that when the brackets were cut off, they were cut off in a downward cut away from, not into the bracket. This would result in a piece on the end of the bracket the thickness of the plate. Then these pieces were ground flush. Now when welded, the fillet weld only consumes the bottom piece (which is actually the original plate) and the original joint is right above the new fillet. With the original rienforcement gone, and the area heated as a result of the second weld, it resulted in the fracture.

In short terms, the plate did not fail. The original joint did. Check the bracket after failure and I would guess that it might be the right length.

jrw159