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another welding horror on the road

mobile_bob

Stainless
Joined
Oct 23, 2005
Location
tacoma washington
one of our customers who happens to be a drywall wholesaler has a fleet for boom trucks and pup trailers

we get a call down to the yard for a repair to the pintel hook

now bear in mind this is a full size twin axle pump that likely is loaded to 30k lbs most of its life.

the tounge is made of 5/16 wall rectangular tubing 3" x 8"
onto the front of which is welded a 3/4 thick plate that is 6"x 14"
with multiple holes so you can mount the pintel eye to set the ride
height for a specific truck.

this plate had seperated from the tounge, in the yard fully loaded as
they were starting to leave.

compound the problem with an illegal air brake system that requires the tank to be fully drained before the brakes set!!!

upon inspection the weld looked nice, very well laid, but with less than 25% of the weld area penetrating the 3/4 plate, and about the same on the tongue tube. the weld basically was just laying ontop.
we all have seen the newbie weld with his new mig, wherein the weld looks real nice but is laying on top of the metal, and when you bend it, it simply pops right off... that is basically all that was holding this thing!

god knows how long it held, we don't normally service the trailers

quite frankly i am surprised it was able to hold the tongue weight the first time it was set down on it. i am sure i could have knocked the damn thing off right after it was originally welded with a few carefully placed swats with a 16lb sledge hammer!!

i have been in this business for 35 years and this by far was the scariest thing i have ever seen bar none.

they want me to weld it back on, and quite frankly after seeing this i am scared to death to touch it!

when you see these things going down the highway, make haste to get as much distance between you and it as you can.

probably not the right section of the forum, because it is a welding matter, but
it is a safety matter i wanted all to be aware of.

evidently trailor manufactures don't have to employ certified welders?

there was concern over a welded motorcycle axle on another thread, it fails and a rider and passenger get killed. a trailer like this loaded with drywall going 65 or 70mph down the freeway would kill everyone in its path.

btw, the safety chains didn't have the dot required clasp's either.
and even if they did, anyone want to trust the guy who welded the tongue plate to weld the safety chains on?

bob g
 
If you look in the metalworking dropbox, under files named "deathwagon..."
you will find a bunch of photos of similar disasters a group member found in
a vehicle that was bought to his shop for service.

IIRC he refused to do the service because it would have been just too much
liability for him personally. I seem to recall he caught a fair bit of grief over
this but in my mind it was the correct thing to do.

Jim
 
I once welded for a company building concrete pumper trucks, I had the job of welding the flanges that held the pump to the chassis, everything got inspected and I believe I had to get some sort of chassis structural certification. Some of the stuff we had come in for service sounded just like what you are saying, complete crap. So many people just assume they can weld anythign because they have a mig welder.

What I say is this, most people can cook a burger, but few are chefs.
 
It is very easy to lay a good looking mig bead with no penetration whatsoever.

Along the same line, I went to buy a new tilt bed trailer manufactured by a trailer company in south west Iowa. I looked over the U channel where the adjustable receiver mount is welded to the tongue. There was a crack along the length of the weld on both sides where the weld didn't fuse to the tongue. It was noticeable because rust was bleeding out from the crack and staining the silver paint. Upon further negotiation, I was supposed to fix it myself and repaint for $50. I'm still looking for a trailer.
 
Once I lifted a 2000 ton hydraulic press with a pretty good size hydraulic floor jack. I set a block of steel on the jack and pushed it right up against the corner of the machine and spent over an hour welding beads over beads over beads with 3/16" 7018 rods. A croud gathered to watch they all figured the steel block would rip off or the jack would not be strong enough. I lifted one corner of that machine about 1/4" just enough to slide in about 1/8" of shim stock and set the machine back down. I wish I had that on video. I bet that steel block is still welded to the corner of that machine at Norge in Herrin Illinois. That was 1977.
 
Pretty scary.
I used to pull trailers(mobile laboratories) that were merely camping trailers stuffed with instruments. Cheap pieces of crap. Pulled them over a lot of bad roads to oil rigs. Our company kept a lot of welders busy fixing the tongues on those things. They just were not made for that service.

... safety chains didn't have the dot required clasp's either.

What are those "clasps" ?
Thanks

SM
 
Well, OK....but I sense a lot of anti-MIG welder sentiment which I don't get.

I have a Miller 251 MIG and I'm hardly a 'good welder' but I can lay down some nice looking beads if I take the time to adjust everything right. Here's the catch - even the not-so-nice beads seem awfully dang strong. This 'you can make a nice looking weld that just snaps off' bit escapes me. When I weld something it's the opposite - I have a hell of a time getting it apart if I ever need to.

My father in law is an old school stick welder type of guy. He hates MIG welders. For years I always assumed he was one of those guys who could really lay a bead with a stick welder. Then, one day I actually had the chance to see him weld and I gotta tell ya, it weren't pretty.....
 
Penetration is not necessarily the issue: correct fusion of the surface is all that is required, and anticipating the effects of the material heat sink on the weld bead. Heavy pieces should be preheated, if the hammer test shows that the bead wants to pull away from one of the parents. We are continually using a big rosebud to warm pieces up in our shop before welding. And we're just machinists ;) :D
 
No penetration is too easy to do with a MIG if the operator has no process experience. It is not the fault of the welding process.

If the weld was done out of position the operator should have used flux cored wire. Old fashioned 7018's have a lot less opportunity for process error. just set the amps and watch the weld pool.
 
Come on, how tough can it be... my daughter is only 3 and look at the welds she can pull off...

http://www.victoriacaruk.com/Vici7.html

It doesn't take preheating, even on a large weldment if you use the right material and shielding gas, AND you prep it so it's clean. Even if it's not meticulusly clean you can do a fine job using wire with deoxidizers in it. It will float the crap to the top and form a silica like coating which just cracks off.

Sure, If you've got a 110 volt mig welder, your probably not going to get there, but with a decent mig welder and the right wire and gas it's pretty easy to get a decent weld if you know what to look for.

The toughest part for Victoria was finding her the hot pink helmet that she wanted.
 
A lot of guys never see the effects of welding because they don't machine their welds. Preheating is better, every time. Can you get away without it? Yes. Less reliable? Yes. More distortion? Yes.
 
Come on, how tough can it be... my daughter is only 3 and look at the welds she can pull off...

Stuart, Little Victoria looks like she's getting a lot of cool experiences. One of the most talented 3 year old welders I've seen!

To the OP's point, my Dad's company made gas stopping and tapping equipment. Some of the nipples you use to add service in the middle of an operating loop of distribution pipe was a simple pipe nipple welded to a saddle with a hole cut out. I worked for the gas company one summer and my Dad was sure glad when I introduced him to the welding foreman, who was happy to do some off-time welding for Dad. Those welds were things of beauty! Given the service, they had to be! Not sure if they did NDT/magnaflux/radiographs, or if they cut sections of samplings of the weld to ensure quality.

Of course, the welding foreman was used to welding nipples to live transmisssion and distribution piping, so he had to be good (Darwinian selection?).

Jim
 
The fact is, IMO, that 95% of the time you can afford to have a "less than ideal" weld because you are welding far more surface than you need.
 
what i am trying to relate is not something that is less than ideal
but something that was akin to attaching with a bead of bathtub caulking
the only fusion that took place was at the extreme edges of the weld
and only a very thin area of the weld.

when you weld the equivalent of a cap plate on a tube, and then place this joint in tension, you had better prep and make a proper weld or it is going to seperate sooner or later, there was no bevel to the tube to get a root pass down into, and
the weld appeared to be a single wide pass done with a back hand mig, using the cheapest wire and some sort of steel mix gas. CO2 allows for more heat getting more penetration into heavy plate in my experience.

i have no issue with mig, but i use the best alloyed wire i can get and i use co2 as well,,, but proper joint prep is of paramount importance
no V and you cannot get enough penetration going downhill with a mig.

i have seen many crappy welds that look bad on the surface, but got good penetration and fusion over a sufficient area to do the job, this job was no where near being a good job. its the sort of thing that gets people killed.

i will try and get a picture of this joke so everyone can see what i mean.

bob g
 
Scariest trailers I have ever seen were car haulers. Friend worked at a fab shop where they repaired them on a regular basis. The frames are typically 1/4" 2x4 tubing. They flex and crack everywhere. I will not remain anywhere in the vicinity of one on the highway now.

I have seen a lot of good welds with mig guns and I have seen a lot of bad welds with mig guns. The thing that concerns me is that I have seem some bad mig welds from good welders who thought they had made a good weld. It is just far too easy to lay down that beautiful bead with only the edge stuck. I'd far rather see a nasty, bird-doo 6011 stick weld with dingleberries all over the place than that pretty shiny slick mig bead. You KNOW that 6011 penetrated, no matter how nasty it looks.

Same story for light stuff. We had a pile of auditorium chairs at the museum. Nearly everyone of them had the same failure... a piece of flat bar that supported the seat was mig welded to a piece of thinwall tubing. One end of the flatbar would cut loose and you would find a beautiful bead still attached to the end of the bar, the outline of the bead in the chrome where it popped off the tubing, and maybe a couple of sewing needle dots where it actually stuck in that outline. Luckily, this was on the bottom, so I could remove the cushion, take the broken chair out to the shop and tig the bar back on, saving the chair. I usually ended up having to do the other end of the bar shortly thereafter.

I don't own a 110 mig. I can do anything with a torch that a 110 mig can do and I KNOW it's a good weld when I am finished.
 
A scary thing is when you hire a welder, with bits of paper saying he knows what he is doing, have him weld lifting lugs on a frame for transporting a $45k machine, then go out with a ten pound hammer and break all four off with a single blow, and have him say they looked like good welds.:eek:
 
"95% of the time you can afford to have a "less than ideal" weld because you are welding far more surface than you need."

Except for those times when you can't. Like when the area is small, and the item in
question is 'mission critical.' Like the motorbike axle that started off another thread that
this one references. Most times when a weld breaks nobody gets hurt.

Other times, folks die. Friend of a friend died, somebody modified the earle's forks
on his bike by cutting them, mig welding them, and then grinding most of the bead
off on the outside to make it look 'purty.'

Yep, the front end folded up at speed and the guy died.

If it's a lawn chair or a cooking pot, sure just glue the thing together.

If it's a motorbike or an aircraft, maybe not.

What about, a vehicle that carries a large load and runs out public roads? Trailers
like that that are gobbed together with mig bead, come apart and kill some innocent
person who happens to be driving near them when the wheels come off - the
owner, the driver, and the welder are all basically murderers in my book.

Somebody says they are going to be doing something dumb, like the brass footpegs
guy, or the threaded aluminum spokes guy, I say right out. Don't do that. It's
dumb. If you do it anyway, you're a moron. BUT if you do it, and drive it around
on public roads and somebody besides you gets hurt - you deserve to go to jail
for what you did.

Jim
 








 
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