Why is this crack filled with brass/bronze??

By Dualie

Date 01-16-2015 07:25

are you sure its not residual paint? Are these hooks by chance a casting?

By PlasmaHead2 (***)

Date 01-16-2015 23:34

Positive, I had one patch polished down with a 240 grit disk just to see if it was only on the surface.
The Hooks are burnouts, I could see the carbon from the cut surface in the sparks as I was grinding it clean.

By Plasma56 (**)

Date 01-16-2015 18:36

While I would be throwing out a guess, I have one for you, defects in manufacturing are sometimes repaired or hidden.
Castings,forgings, welds in general could have voids, fishers repaired quite acceptably and the use of dissimilar materials could do this will no issues being presented. Think fiberglass and bondo in fixing a rusted or dented panel in the whip.
Using a low temperature brazing filler, RBCuZn-C, with say Oxy - propane, could actually do this repair with less metallurgical disturbance then a rapid heating and cooling from a welding process. Think arc strike.

Having said that...most manufactures won't don't do that. We have codes and standards to follow and process improvements implimented to prevent this happening. We recycle. Throw it out and get a new one. Not to mention, most are not taught to do repair work. Repairs require thinking.
Labour costs to repair these days typically exceeds the cost of a new one. See it every day.
People get used to making a payment and it becomes a way of life. Remember when air was free? Water came from a tap? People used to spend the weekend keeping there car running.
However, we also import. Those places...labour is cheap and materials cost plenty. It gets fixed in those places.

But remember, it's just a guess.

By PlasmaHead2 (***)

Date 01-16-2015 23:43

Hey Plasma :)
These hooks were burnouts with the brass attached after the fact by what I can only guess was torch brazing... They were fairly mangled and all hints of the original process were long removed.
the chamfer on the edge of the hook was mostly original... The brass filler didn't quite fuse all the way around....

Once the cracks were discovered the owner/customer decided on getting new hooks. Thankfully. I was NOT looking forward to trying to play "fix the crack".... :eek:

By PlasmaHead2 (***)

Date 01-16-2015 23:50 Edited 01-17-2015 00:07

More pictures.
Due to these things being scrap, I was plotting to ask the customer if I could cut out a chunk or 2 of the cracked areas for experimentation and/or because I think it looks kinda cool :lol:

*Further note, Those patches of brass that you can see in the pictures disappear before the cracks do. Other sections of both hooks showed the same thing and every time the brass vanished under the disk but the cracks did not.

By Plasma56 (**)

Date 01-17-2015 10:16

Plasmahead2,

You take nice pictures... and the pictures explain alot actually. Thank you for including them.

While still a good guess, those hooks or similar I have seen before. My guess, you are correct to assume a previous repair. The edges and contact surfaces had wear and of the options for repairing those surfaces, from my point of view, this was the most practical, affordable, and sound in judgement. Let me explain.

With the option of total replacement off the table your left with methods of repairing.
The methods of repair would be building up and machining/grinding to size shape. Or placing a wear surface pad/patch to reshape the worn area and then a method attaching it. The option of repair with a replaceable wear surface appears to have been done. Maybe it was slightly over done.

With conciderations for welding with a metalic arc process to this material, welding a material that thick with a brazing process reduces some concerns. More serious cracking risks being one of them.
You did a lot of grinding. Before I include the punch line of those cracks let me enlighten you.
It was over welded. It's a wear surface. That brazing filler has a tensile strength in a direct pull of approx. 53kpsi. How much grinding did you do? Seemingly over welded to hold those bars in place and during the welding, the material surface was over heated. Punch line, blame the welder.

My guess, while the actual base material played a roll in the surface cracks, a little more carbon and maybe some manganese in the material increased this risk, it was no or poor preheating along with over heating and base metal cooling contraction that brought about this occurance? The brazing filler most likely used doesn't thin as much as you might think depending on it's composition. This brazing filler has to be really heated excessivly to be that runny in viscosity to crack fill.

I wouldn't be worried about sleeping at night. Judging by the pictures, you can guess the thinning and spread of filler metal was from over heating and poor torch control. Having said all that, the guy probably used a cutting torch because most don't own a oxyfuel tip of the size required to do that job. It will do the job, just with poor control.

I have to tell you, I wouldn't just rebraze it. I'd do the same type of repair, shaping/ forming a fresh wear surface out of flat bar, but I'd preheat uniformly to around 450F and with the idea it isn't going to going anywhere, stitch the seam edges with some low hydrogen filler, maybe E7018, followed with a bit of post heat and call it a day. One thing to remember, I'm guessing repairing this surface is less work then repairing the part it hooks to... don't make it to hard (the wear surface) and please don't over weld it.
Remembering 70,000 psi, ask yourself where is it going to go?
That was alot of grinding. How are your arm's feeling?

I have a couple questions for you. How many hours did you quote to do the job? How many did it take. And how did you tie it all together?
My guess, 4hrs, done in just under with a small coffee break and some steady eddie working and not brazing. Anywhere close?

By PlasmaHead2 (***)

Date 01-18-2015 16:15 Edited 01-18-2015 16:26

Hey plasma,
I only did a little bit of grinding... However I did A LOT of air chiseling... That killed the arms/back but made a hell of a lot less dust. The attached pic is of some of the chips I was getting.
It took me about 8hrs to get the old brass removed and cleaned up. I admit I was not totally busting my self. :roll:

If I had huge stacks of these to do then id have a more efficient way to get it done...
We also have a lack of equipment at the moment due to new hires and lack of buying new things... So all the new guys had the 5 inch grinders with the cutoff wheels...
Per the original plan of attack we were going to form up some Aluminum bronze flat bar and braze weld it in with GMAW. No need for steel or torches aside from a touch of preheat.
I have no idea what the numbers were for the quote, I'm just the minion who has to do the things they come up with :grin:

By PlasmaHead2 (***)

Date 01-16-2015 23:50

Hey Al,
These were plates brazed to the ID of the hook surface. No pushing, lots of chipping and hammering and wedging... I really didn't want to make that much grinding dust. :twisted:

They may have been repaired before, not totally sure about that.
Could a brazing repair on a cracked surface pull braze material into the cracks?

By 803056

Date 01-17-2015 02:03

In that case, absolutely.

In order to braze or braze-weld (there is a difference between the two terms) the bronze or brass to the ID of the holes, the base metal has to be heated hot enough to melt the filler metal, but not the base metal. Still, that means the hook has to be heated hot enough to melt the filler metal. Capillary action will draw it into the cracked region that is hotter than the melting temperature of the filler metal as long as they are fresh, oxide free, and free of all contamination. If there is oxide or other contaminate, the filler metal will melt, but not bond to the base metal.

Best regards -Al

By 803056

Date 01-18-2015 01:49

OK, now I'm confused. Are you talking about a hole that was built up with bronze to act as a bushing or are you talking about the gullet of the hook from which the chokers hang?

I thought the conversation was a hole that was built up and then machined to act as a wear surface for a pin.

Any lifting device has to be approved by a P.E. and they are usually proof tested to meet OSHA requirements.

Best regards - Al

By PlasmaHead2 (***)

Date 01-18-2015 16:25

Al,
Sorry for the confusion, I was talking about the gullets of the hook.
No surfaces on the hooks were built up and machined down, just strips of what used to be .5 inch brass brazed on to the hook.
I admit I have no idea about how they are dealing with the engineer requirements... I believe the customer is handling that.
Thanks
-Clif

By lo-hi

Date 01-18-2015 23:36

Why were the hooks bronze coated, wondering if they are working in an explosive environment. Maybe the initial fame cut set up the scenario for the brazing process to eventually cause the problem.

By PlasmaHead2 (***)

Date 01-19-2015 22:48

I believe to preserve what ever the hooks were picking up, from the rounded off edges on the existing brass id guess some sort of roll.
Didnt look like they were too gentle with it either...

By Plasma56 (**)

Date 01-19-2015 00:13

Things keep getting clearer. The mud is settling.
Knowing you removed a brass/bronze strip explains the need for brazing the strip or more correctly in generalizing, a non ferrous filler metal being used.

I'm also willing to suggest next time you bring out a gouger. CACA, Carbon Arc Cutting with Air. It will remove non ferrous materials. Between you and me, PAC would have removed it as well. Both are noisy and smoky but quicker and faster isn't so bad at the end of the day.
Don't get me wrong, you did get it apart. But at what cost?

I'm going to interject for a moment. No harm no foul intended.
Tell the boys the next time they are around the coffee table I said they must be dumb. Only option left would be deaf. I know if I heard that much noise, I'd be walking over to ask when it will stop. Any man that fails to see you making that much noise, for that long a time, without seeing it and offering a better way, well... pick one. Didn't take me long. I wouldn't pick deaf.

Shop dynamics and personalities... Remember, if you’re not part of a cure you could be part of the problem?
When that job is done, print these pages out and share it with the boys and talk about it over coffee. One man can and does make a difference.
Best be the cure.

In the old days when a braze weld was more in flavor, in a pinch, stand it on edge to get gravity working for you, grab a cutting torch with a mildly oxidizing flame, bring it in close to melt and blow with low pressure blasts of oxygen. You'll wash enough out to allow an air hammer or hammer chisel blow to fracture the weakened remaining bond apart. Unless they beveled the crap out of it in some poorly thought out thinking, that maybe they were doing something of brilliance before hand to make it stronger, it wouldn't have flowed that deep between tight surfaces but given a gap and over heating, it could be work. And you peeled out some material to prove it.
Quick point of mention. Notice the color. Redish, not yellowish. Your filler had a lot of copper in it. Color is another means of identifying metal. Point is it didn't scoop like ice cream did it? It chattered every step of the way. Copper is high in that one is my guess.

Ok, I'm revising my estimate. Not by much however. But you won't like it. Your over budget.
Your wear surfacing material just complicated things didn't it. Did for me.
Relax...this time we skid the estimator.
But someone has some explaining to do.
That material, if not easily found now that it has been removed, isn't the only problem. The second will be shaping it and replacing it.
How bad was the wear and where was it worn? Would repair by buildup have been a seemingly better option with this in hindsight?

I apprenticed in a small shop that did that and any other crap, repair or fabrication that would make a buck. My boss, great man. He didn't miss a chance to bring in work. He was a very good mentor. He explained things. But he also forced me to think on my own with his explanations.
Now having the very important knowledge of the material being non-ferrous, the surface could possibly have been more easily and economically repaired by rebuilding the surface and refinishing. Can you show me a picture of the wear in greater clarity? Not that it matter but I could be wrong.

Clif... buddy, do you have an estimator taking in jobs? Someone should grab a magnet. While I guessed close as to what and why with a bit of information and how, the use of a brass/bronze wear strip was a point worthy of mention. My guess, a softer hard surface, slippery enough to reduce friction load wearing on the part they hook too, it may also have been to reduce sparking risk in a hazard filled environment. I'm guessing heavy container and friction issues.
But a simple material test would have identified this. Magnet, file or chip test are forgotten tools.
When estimating the degree of perceived difficulties in making effective repair, material identification is #1,

Hey...depending on how long it took to figure this out, what may have been missed in job difficulties, is second to who got told in the food chain and how's the customer going to react when he gets the news or sees the bill.
Thinking auto repairs, screwed again...
One welder to another welder, I hope you spoke up quickly when you discovered this. Things look like they are going South.
But you broke it so you bought it. Someone has to explain something with a straight face and if I was the guy paying, it better be a good story.

Estimate to rebuild surfaces.
6.5hrs.
-1.5 prep and preheating, 3 - 4 welding build up, 1 hr post heating, surface finishing and clean up. Phosphorous bronze would be my choice for filler.
Your shop appears well equipped. That's good. I think you have a can of worms opened up.
Having said that, would it disappoint you to hear, my estimate is actually quite high? It is. It comes down to equipment.
Have you seen spray torch technologies?

Welder to welder, you can't afford it all. But if your buddy had it and you could make a bit by being the middle man, and the customer gets a better solution, who's the winner, everyone. Good will carries farther but a bad reputation follows. They call it paying for making it easy for them.

Far be it from me to suggest, but don't throw those pieces in the scrap just yet. At this point in the game, plan C is looking good. How's B working out? Like a tailor, sew sew. On the bright side, experience is an excellent teacher. And we have all worn the shoes.

Keep us in the loop Clif. I think you are going to say the familiar words, if I had to do it again...

By PlasmaHead2 (***)

Date 01-19-2015 23:11 Edited 01-19-2015 23:18

I thought I did everyone else a favor by NOT bringing out the CAC torch :wink:

They hate that thing more than the noise I made with the chisel.... :twisted:

Some parts of the brass were so rounded off that the original braze was gone, I dropped a chisel in and hit it with a hammer a few times and got a good 6" section to spring free...
The air chisel made it even easier...
As for the time it took.... well... Have you ever had those days in the shop that are Real slow... and even the manager/estimator says "take your time".... It was one of those days.
We work with this customer a lot so all is good, the time will wash out somewhere. Im well aware that it all could have gone much faster. None up the chain are loosing any sleep over it and a few even thanked me for finding the cracks when I did, including the customer...

The reddish color was the rust from the hook surface under the brass. It Did in fact scoop out like ice cream with the chisel. I made a point of showing some of the machinists the big curls and mocking them over how big my chips were :eek:

Then I ran and hid from the flying objects :lol:

These hooks are done. No saving involved. The customer was called in as soon as the dye pen developed... half an hour later the hooks were pronounced D.O.A. and new ones placed on order. Not sure if we are going to do anything to the new ones or not.
Now I have to figure out how far away to torch cut out some chunks of the crack so that I can fit it in a band saw, and not disrupt the crack/brass pattern.
Thanks
-Clif

By Plasma56 (**)

Date 01-20-2015 08:52

Clif,

Tools make the difference. If it was your chisel or the CAC-A/PAC in the shop, I'll take the noise and the chisel. Remember, I didn't say it was a bad choice... Pause ... I didn't. But I agree, avoid the dust, and reduce the hazard. Assuming I couldn't send you outside of course, I can't lose sight of making a buck.
Just curious, thinking of the possibility the wear is more to one side, any chance they could have been switched left to right sooner to prevent this? Just wondering loudly.

I wouldn't worry about the time. It wasn't harm or a foul, or that bad, it was education. Sounds like they understand at work. Heck, I support your discoveries.

- As I say, the less they know, the more we make."

That statement clearly taken out of context sums this up. I think those cracks you uncovered will one day have you say... he was right.
Clearly, I didn't say I was right, I said, he was right.

Will you be really surprised if the new one comes in with a strip brazed in place? I would. I'd expect an adhesive to be used.
But I'm also curious. IF you find out let us me know will you please.

Don't throw it out or cut it up just yet. I'm guessing it would be best described as a shape cut from a plate, hole drilled at one end and a wear strip brazed into the cradles. Manufacturing rocket science 101. I say rebuild it if the boss let's you when things are slow. Then hang it on a wall as a reminder.

Those cracks, work that grinder with a bit of flat pressure to knock down a bit deeper and disc polish the surface, blow a bit of disc dust if no crack shows and see if a crack makes an appearance. It might. But if you knocked it down a bit check again with the dye pen... I'd be surprised to hear any cracks were still there or very deep. I'd still say whatever you find has probably been there since day one as previously mentioned and not a concern.
It's not the end of the world, it a slab of metal. That brazing didn't hurt it.
But if you believe in things, you don't understand, then you suffer.

Cli, if you find a crack that deep, this will be my hill to die on. I'm calling the bluff. All in.
If you say you find a crack extending 3mm deep, I will admit defeat. I'll go away.
You would please a lot of people with this proof.

Tell us what you discover. I'm confident. I have a good feeling about this. I might suggest if possible, keep an open mind to discovery. Take a moment and think about what you are about to look for and why. Where it's found? What caused it? Think about how the steps you take support what you wish to prove or dispell. It could save you a few steps. It will allow you to go deep enough as well to ses the depth of what was affected. HAZ or crack.
Tell me it's cracked to a depth greater than 1/8" and I'm outs, gone, good riddance to bad advice.
I place my odds at 50/50.

Less to the point Clif,

The last time I looked up AWS, the W was for Welding.
Yea, welding. Go figure. It seems to be a moot point in all this.
What came first the welder or the code?

The A and the S, fine...I get that. But fear mongering the Welding, it's just wrong Clif. I trust you to be a smart enough guy to see that.

AWS Mission Statement
The mission of the American Welding Society is to advance the science, technology and application of welding and allied joining and cutting processes worldwide, including brazing, soldering and thermal spraying.

Clif, This is a bit of work for you. I understand if you want to call it a wrap. You're doing all the work. As far as I'm concerned, your a stand up guy. Over and above. Thank you. I'm proud of how you stepped up here.
If you could however, I'd appreciate your efforts to continue on. Between you and me, I don't care one way or the other all that much. But I do care that you get more out of this then what you have. And you will. Stay the course. It's making you stronger.

IMO,
Noel

By ssbn727 (*****)

Date 01-19-2015 09:06

Now those are words of wisdom Al!

You covered the pertinent details as always and more important, concisely described why this sort of repair should only be performed specifically per the engineer's instructions with his or her name on it, or else the vampires come out of the woodwork to feast on it's prey once the dust settles. You also described the option of simply replacing the part instead which for the materials being used, would have been my choice... Clif, sometimes we get thrown a bloody carcass and then are asked to perform a miracle when one simply isn't possible... If one would take a serious observation of the situation, nine times out of ten, the reasoning used just doesn't make sense but unfortunately the big shots rarely listen to what the welder would prefer instead... It's a catch22 for anyone put into that sort of situation and can truly make you scratch your head enough that you end up losing all of your hair in the process. :eek:

Respectfully,
Henry

By PlasmaHead2 (***)

Date 01-19-2015 23:16

I hear you and Al loud and clear, Hank :smile:

I'm kinda hoping that I if I polish up some segments of the cracked hook I can get that nifty pattern to show up better.
Maybe ask the waterjet guy to slice some letters out and tack them together?
It all depends on how deep the cracks go, but I'm gonna find out :lol:

Thanks
-Clif

By PlasmaHead2 (***)

Date 01-19-2015 22:43

Hey Al,
Your missing the time line, let me clarify.

The hooks came in with badly mangled brass liners (pictured above next to the hammers) and the instructions to replace with either brass/bronze.
In the process of removing the old worn out liners, I discovered those cracks.
The customer was called in, the hooks were pronounced boat anchors and new ones are on order.
Now all thats left is for me to figure out how far away from the cracks I need to torch cut so that I dont disturb the cool looking effect. I want to saw them up and polish some bits of it for fun.
Then its off to the furnace to become cans/cars/whatever else...
They were torch cut from 2" plate, why that vs forging I have no idea. The brass liners seem to be to spare whatever they are picking up from wear, some sort of roll I'd imagine.
I would NOT have attempted any repair on the hooks as is.
All is well, no attempting to breathe life into a long dead horse carcass :lol:

Thank you
-Clif

By Plasma56 (**)

Date 01-20-2015 23:29

Clif,
https://www.aws.org/cgi-bin/mwf/topic_show.pl?tid=34153
You got a hand out.

Re-read all the posts. You took advice from a very smart man but he was two steps behind and still is on this issue. If the advice supports one's own interest is that not with a degree of bias? Is it really in your best interest?

>They were torch cut from 2" plate

You think this is rocket science, it isn't. Told you as much. I have seen a rocket, this isn't it.

>I would NOT have attempted any repair on the hooks as is

And asking advice was a good first step. But even as you re-read the posts, no where was it said it couldn't be done. So what advice did you really receive? I have a library that says it can be done. I have experience that says it can be done. As a matter of fact, I've seen the same part as a grunt apprentice years ago. My guess, hooks used on a container truck. I'd worry more about the truck, brakes and steering and if the load is secure.

>no attempting to breathe life into a long dead horse carcass

Excuse me? You will be eating those words. Make no mistake, I've eaten many of my own. Those are classic. And the horse isn't dead, but your killing the poor beast just because it's easier to do then throw a new shoe on it's feet. Wonder why things cost so much...

It's all good. But I'm getting tired. The road is long. But it will get short quickly.
Respect your elders, but don't trust what they tell you to be true at all times.
Think for yourself, but use the knowledge and wisdom gleaned from others to guide you in finding the answers.

The rest of you boys...and I don't mean the regulars, you will see, we are your peers, not gods to be worshipped. Men.
Some just dress a little finer and use spell check more often.
Knowledge is wealth. Information gives you power. Some clutch it tightly and charge for it when others seek it, some just give it away freely.

These guys have delivered that in droves,freely, they have my respect and should have yours as well.
I don't always agree, but I do mostly respect the opinions they share as freely as they do.

Change is a good thing.
Eventually this room will be quiet without it. I choose to be here but I also choose to go. Damn the results.
I have had enough. I need a change. I'm a welder. I quit.

Quiting because you don't want to anymore is ok. Like smoking. I choose to quit.
I came for the welding, what did I find...The blind stares of a million pairs of eyes, all surprised, trying to figure out the codes who don't understand welding.

I'm going to buy a tractor and switch forums.
http://www.mytractorforum.com/
Lots of action with tractors.

My musings here have run the course. Without weight or value to any further conversation, thanks guys, It's been a slice.
A slice of sweet sticky pie.

No offence intended, and with all do respect, don't forget the W.
I need only read the postings, you are inspiring men. I've lingered too long on you're words.
But I remind all in my quitting, we are all just men. It's what we leave behind that defines our legacy. Life is best lived with an open mind.

Jon. I don't think we've talked before. I've read your most recent post and was bummed right out. My thoughts are with you.
You have as well been a source for knowledge, support, and insiration to me. Thanks...
If your reading this, I think you understand better than most my sentiment.
If it offends you, please accept I mean no disrespect, but I couldn't express it better and your post about sums things up for me.
-----------------------------------------------------------------------------------------------
Topic Minimum Distance of welds?By jon20013Date 04-10-2012 12:33
"You have to do it because the code requires it." is the biggest cop-out practiced by inspectors and QC departments around the world."

That may very well be the most astute phrase I've ever read in the Forum. Hope all of our lesser experienced folks read that many, many times.

There is usually (but not always) a rhyme and a reason to what's written in Code... but don't think for even one second that just because something IS written in Code (or on the otherhand, isn't) that it necessarily makes something right or wrong. There are some absolutely brilliant people serving on code committee's, but there are also a bunch of narrow minded people as well. MOST of the time they /we get it right thanks to the consensus process.
--------------------------------------------------------------------------------------------

Clif, you will learn in spite of us. Good luck in your endeavors.
I leave you in capable hands. Smooth,soft,capable hands.
Best regards,

Noel Chyz

By PlasmaHead2 (***)

Date 01-21-2015 02:58

Noel,
Putting new brass on a sound but seasoned hook was one job, fixing the cracks and ensuring that it was a part I would stand under whilst loaded... thats another issue... one that I would not want to deal with. Not when new steel plate and oxygen and acetylene gas are as cheap as they are...
Now, that being said... If this was the last pair of hooks in existence and all of life on earth depended on their continued use, well we have a fun challenge dont we?
I'd start by sending it off to the heat treater for a nice anneal then follow with a full UT and X-ray work over, mapping out any existing crack or flaw. Some gouging and welding followed by another trip to the oven. Another round of all the NDT methods at hand. Then maybe to get around the whole issue that caused this thread in the first place, id bend up the brass and Bolt it on. :eek:

Send it to the water jet and put some tabs that bend around the outside of the hook so that the bolts dont get mashed up by the load and replacement is easier. Or just sink them in the wear face and deal with cutting them off with violent means when it comes time to repair them. :twisted:

Now for the other fun hypothetical... Stuck in the field having to repair the worlds WiFi supply device (because people today need wifi more than oxygen water food ect :twisted:

) and it needed a new hook with brass liners...
I could trace it out on a plate, cut it with a torch by hand, use a mag drill to cut the lifting hole( or a 5" grinder with a cone point hard stone to clean up the torch cut hole...) and line the whole sucker with brass by the tack/clamp/smash method to form it around the curves of the hook, Inside of 48 hours (adding in for lots of variables like the worlds wifi device being in the north pole and having to fight off polar bears while trying to weld)
In a nice shop with good toys up to the task at hand, I'd see a 10 hour day; 12 if I have to unload the plate and bar stock from the truck my self...

I was planning on doing a bunch of section cuts to get the full picture on how far they go into the hook. they will never again lift anything except for a few pencils or business cards if I can get a few pieces long enough with the cracks...

Any ideas on how to reproduce the effect seen on the hooks? How do I get a bar of steel to crack and suck braze metal into the cracks on purpose?

Thank you for the fun chats :smile:

-Clif

By Lawrence (*****)

Date 01-21-2015 12:19

In response to a poetic stream of consciousness.

A welding Haiku:

Debate and metal
A storm gathers high above
It is in the code

.

By PlasmaHead2 (***)

Date 01-22-2015 03:52

Well played :lol: