Ok, I have seen a lot of different posts around here about bad welds. Most of the welds are garbage, but often not the biggest problem. If you have some pics of a dodgy weld that has failed, post it here and hopefully an expert or two can help with a fix. My opinion is that, for example, the bracket in the picture below failed because there was insufficient bracing. ( but yes, the welds are crap.) BTW - I stole the pic from another thread.
I've seen more bad welds than I personally could ever imagine, but never bothered to take a picture, because, well, I like good welds, sorry.
Last summer my cousin had a CJ-7 that the frame was so rusty on it broke in half. Wish I had a picture of the "welding" someone did to fix it. They didn't even try to clean the rust off of it. Probably the worst welding I've ever seen and then someone traded a 90's K1500 extended cab for it.
It's never crossed my mind to take pictures but ............ In many years of working with steel I've seen everything from beautiful looking welds that gave up under light loads to really ugly ones that held up through hell, and of course both opposites as well. To be quite honest most of the failures I've dealt with were indeed exactly what you stated, structural design stupidity.
A weld can be very uguly and still be plenty strong. Just 'cause there is spatter everywhere and extra slag doesn't mean there is not good penetration. And you can certainly do some very pretty welds that barely penetrate and aren't worth shit.
That and alot of people have not masterd the art of welding upside - down, or vertical for that matter.
Seen a lot of lumpy "beer goggle" welds that held up fine through some severe stressing, and then saw a beautiful factory weld on the gear leg of an aircraft fail, (admittedly after 40+years) that on close inspection only had about .020 of an inch penetration. The main thing ain't is it pretty, but is it deep and complete.
yeah looks like the metal surroundingsheared, then again metal around the weld(if good) is alittle weaker.
That photo looks familiar ... Was that the old Merc or Lincoln (can't remember) with the really crappy C-notch and "four-link" job? The lower links of the four-link were just welded to the upper ones. It was a green Lincoln or Merc that looked nice from the outside.
factory welds from the 60's and 70's are amazingly bad, doing clips you come accross some, i had some where it looks like the welder fell and dragged accross the frame leaving a long scar behind.
How do the manufacturers compensate for differences in metals they use. Do the robots calculate the necessary weld as its welding, or is the metal so uniform it doesn't matter, or what? I'm no metal man, so maybe the answer is simple, I just wondered though.
Where major manufactures have large variations in metal type and/or thickness they tend to bolt or rivet them together. Most robots are "dumb" and follow paths determined by their programmer or an engineer. Very few actually 'calculate' on their own. There are ways to weld really thick to really thin, but without some serious thought in the design of the product, and the welding procedure ( pre-heat, direction of travel, length of runs, post treatment, ect. ) a crack will normally occur.
there are two approaches to using welding robots. 1) a dumb robot that exactly follows a programmed path. it requires precisely cut parts and precision jigs to present the weld joint in exactly the path the robot will trace. B) seam tracking robots that sense the joint with lasers or filtered cameras and adjust as the weld is laid down, but they still must have the basic path programmed.
A guy I know bought a wal-mart bike for his kid, he just started riding down the street when the neck broke off of it and the kid got injured so he sued and got $30,000 from wal-mart.
I am just glad someone knows how to put a bunch of cars together at one time, it would take me a couple of years to build one from raw.
i am an ironworker, i do a lot of welding. i learned how to weld at 15. i do not like to think i am the best weldor around, but i am a pretty good weldor. innershield, tig , mig, stick. i find myself sometimes shocked of the very poor quality of welds of some of the weldors out there. they dont have to be pretty to be good, but damn some times ugly just doesnt cover it.
http://i104.photobucket.com/albums/m177/49Cosmo/3spodfloorshift.jpg Here's mine. You can see where I fabbed my own shifter dogs to shorten the shifter pattern on this '62 3sp+od. I am not proud of this weld, but it is what it is and has worked for 6 years this way. I am a daily driver and my '49 chevy 1/2 ton is my only vehicle, repairs have to be done to get to work on Monday, so Quick and Pretty haven't met yet, Quick and Ugly are fast friends. If anyone can direct me to a tutoral site for stick welding, I have a Craftsman HD 25-230 ($30 at an auction) I'd be oblidged.
There are weldors and then there are rod/wire burners. I've been at it for 30+ years and have been the leadman/weld inspector/weld repairer at a fab shop the last 24 years and dealing with half-a-crap welds are my life. And I can positively tell you one thing: you either have it, or you dont, and if you dont, you never will!
i wish i had some pics of the welds on this '56 chevy that was in the shop a few weeks ago. they put a late model clip in the front and then "welded" it to the frame. the welds looked like that popcorn celing texture. lots of gaps between the spatter too. i got out from under it in a hurry and put it back on the ground
Hold the stick at 70 degrees to the path of the weld, keep the arc at a nice even gap ( takes practice ) and adjust the amps to suit. Probably not much help, but you just have to be really smooth with the torch movement, if you can feel it pushing back you're feeding it in too fast.
I always wondered what it would look like if I held a mig tip 6 inches from the work piece and let it go Kind of like the old "fireman and wild hose" gag
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