WHY can't you remelt a stick bead with tig? Russ? anyone

[Dawai]

I am confused, it looks like it would be the same as adding rod? If you remelted it all into a nice uniform puddle? DO they think penetration would be a issue?

A Tig weld that looks good on top, bad weld underneath?

The older low powered mig machines were like that.. make a pretty bead on top, but not penetrate and make a good weld.

Ever see the pipe "rings" you clip down in a beveled pipe joint to tig weld in?

[NickH]

Why on Earth would you want to do that?
Surely if you have MMA & TIG but want welds that look like TIG it might be a plan to use TIG to start with.
Nick

[loose nut]

Can't say that I have ever tried it, some types of material will get shrink cracks if you don't add filler rod to the puddle so just remelting can be a problem there. If the bead is cleaned properly it's just metal and if you where doing lace welding, 50% over lap, you would be remelting the base bead and can get good fusion but again you are adding filler metal. You should be able to remelt the bead and add a bit of rod, if the original fusion was good then the new bead should be good.

[Dawai]

I have a three wheeler frame here, done with stick.. most welds are consistient, look to be penetrated.. I ground some of them down flat..

BUT in places where I would not like to bondo over the beads I'd like a "pretty weld".. if you know what I mean.. Pretty to me is a nice tig weld.. I have a front end made up with 2x2 sq tube.. a huge springer.. it is the same way.. I dislike any bondo over welds. I could build up a big fat bead and grind it flat I guess?


RE WHY:
I bought this car once.. it had bondo over the frame clip job where it had been totalled.. you could not see the crack in the frame till it broke.. the first part of the frame was rusty so.. it had been broke a long time.. Meaning I was jumping railroad tracks after it was broke.. Covered in paint, then lots of grease it was a f-ing mystery till it broke and lot's of play came into the steering wheel.. (car trying to steer on it's own)

The lil CRX I got here now, it was clipped with a frame section after being rebuilt.. they brazed it.. it is a part that just holds the front section and sheetmetal.. not suspension, in front of it.. I had to rebraze it.. everyone assured me I could not get the braze out..

Out came the Henrob.. what a wonderful lil torch to braze with.. It too had bondo on the repair to hide it.. IT was in magazines.. so.. http://img.photobucket.com/albums/v85/ibewgypsie/CRXinmag.jpg

The whole thing is, you can take a turd.. spray metalflake on it and everyone will OUUHH and AHHH over the sparkly.. but down under the bad welds are still hidden.

Really want to be scared? get under your 70s gm car and look at the welds on the "two subframes" under the car.. man.. all the ones I have had must've been made on a friday, or a monday? I liked to have wet myself looking at the welds on a 396SS camaro.. It had a 4 speed too.. and that popping noise? was it the frame or the rear springs?

http://img.photobucket.com/albums/v85/ibewgypsie/CRX.jpg

What it looks like now.. all the good stuff is gone.. I got a decent engine/trans in there..

[Bob Pekny]

I've done that many times. Used to do a lot of stainless weldments for boats and would mig them, leave the welds slightly short, and finish up with a tig. Also if the mig wire feed was a little fast and the weld was a bit humped up I would go back over with a tig and blend the hump down. This is way faster than just tigging the entire weldment.

[radkins]

I've done that many times. Used to do a lot of stainless weldments for boats and would mig them, leave the welds slightly short, and finish up with a tig. Also if the mig wire feed was a little fast and the weld was a bit humped up I would go back over with a tig and blend the hump down. This is way faster than just tigging the entire weldment.





I have done the same quite a few times but I am not sure exactly what it is he is asking, I have even done this with Oxy/Acetylene. Not long ago a guy brought me a tank to re-weld because he was not satisfied with the appearance and he wanted me to grind it down and TIG weld over the 7018 welds, this was a square oil tank that had been made from 1/8" that had been stick welded (3/32" 7018) and was rather rough with questionable leak integrity. Instead of grinding the welds I simply wire brushed the entire welded area and proceeded to simply make a pass over all the welds without using any more filler at all. The finished tank looked really good and looked as if it had been TIG welded from the start, not sure if this is what he was asking about but it usually works pretty good.

[Dawai]

I think it was on the Miller forum where I read you can't, or are not supposed to tig Stick welds.

Heck.. Melting metal, flowing it together right at the Dropping out temperature is a solid weld whether it is gas, tig or stick. Unless you temper it "brittle hard" or anneal it by inclusion of other metal or gas porosity I guess you can't hurt it. Most welding rods are ten times better than the parent metal. Getting them all to flow together and Look good is a problem thou.

As a welder I am a good electrician. Most electricians think they can weld. Thou I passed a cupon test or two I have gathered some eyesight problems. I weld a lot of times by sound and the braille method. Getting old sucks.

Where's dat Russ at?

[davidh]

I have a three wheeler frame here, done with stick.. most welds are consistient, look to be penetrated.. I ground some of them down flat..

BUT in places where I would not like to bondo over the beads I'd like a "pretty weld".. if you know what I mean.. Pretty to me is a nice tig weld.. I have a front end made up with 2x2 sq tube.. a huge springer.. it is the same way.. I dislike any bondo over welds. I could build up a big fat bead and grind it flat I guess?



What it looks like now.. all the good stuff is gone.. I got a decent engine/trans in there..


now that would make a cool little rotary pontoon snow car. . . . .

[radkins]

Getting old sucks.



Until you consider the alternative! :eek:

[torker]

David... I've also done the "make em" pretty with tig many times. Mainly for what Bob Pekny says....to blend in a few humps or flatten out and melt in a cold lap...mostly just cosmetics.
The biggest complaint I have with tiggin over a stick weld is many times there can easily be a bit of dirt trapped in a part of the weld that really makes very ugly porosity.
Then there is the tension difference between the top side of the weld and the underside. The extreme temperature of tig could upset that.
It could cause cracking.
That's only a concern with multi pass stick welds.
All this is "So I'm told". I was taught that 20 years ago...but have never had a problem with any of my touchups cracking.

[Dawai]

I have a "Fad" tee bucket frame here too.. Welds were laid on big fat caterpillar beads then ground down flat. Hunps and divots filled in with more bead and ground some more.

NOW How do you know how much bead "web" is left? I do not possess eyes like superman.

I have been going to add in some gussets in places just in case inside the frame.


OHH (explanation of paranoia?) in the 70s.. people would take a harley, cut the down tubes.. push down on it with a jack under it till the LONG grasshopper front end was close enough to the floor, then insert slugs into the downtubes, weld them up and "BONDO" them over. On a ride in Chattanooga, it was memorable, Tiny's bike sat down on the engine. He rode it out.
THE poor welds broke, hidden by the bondo. NOW, unlike the STONED TINY who rode slow, I stroke the road when I ride.

[JRouche]

Ok, not saying its right but I have used the TIG flame to clean up an ugly bead, my own ugly beads :) Yup, Ive used it like a paint brush for metal. I haven't done it with stick beads, I dont do any stick welding. But to pretty up a MIG bead, or even a nasty looking TIG bead. I dont have any problem going in there with the TIG flame and smoothing it out some. Im just flowing metal. Thats one of the reasons I like TIG welding. Its a pure flame, inert, just heat. Ill contour a bead to make her perrty. Just watch the under cutting if you dont add filler. JR

[psomero]

David... I've also done the "make em" pretty with tig many times. Mainly for what Bob Pekny says....to blend in a few humps or flatten out and melt in a cold lap...mostly just cosmetics.
The biggest complaint I have with tiggin over a stick weld is many times there can easily be a bit of dirt trapped in a part of the weld that really makes very ugly porosity.
Then there is the tension difference between the top side of the weld and the underside. The extreme temperature of tig could upset that.
It could cause cracking.
That's only a concern with multi pass stick welds.
All this is "So I'm told". I was taught that 20 years ago...but have never had a problem with any of my touchups cracking.


uhh, heat is a lot more controllable with TIG than it is with stick. i'd love to see someone try to stick weld a bicycle frame together that has .025" thick tubing...

[torker]

uhh, heat is a lot more controllable with TIG than it is with stick. i'd love to see someone try to stick weld a bicycle frame together that has .025" thick tubing...
I know that. You missed my point. In order to melt the bead you are NOT going to do it at the same temp as you would when welding your .025 bike frame.
You are melting the bead FROM THE TOP DOWN...try that with little heat and you won't get any penetration.
You are goin to have that bead wicked hot to melt down as far as you should.
That's where you end up with differences in the temper tension of the different levels of passes.
K...now I'll get back on my turnip truck :D

[Dawai]

YES SIR..

and.. the whole thing about beveling thick tubing to tig weld in.. I see people just tigging stock car roll bars and stuff..

HOW do you know the welder had full penetration? did he just weld .032 of top surface? Or .25 of tubing wall thickness..

I got a mig made in the 80s.. it does not have enough heat to weld car-trailers or other structural steel.. now the one lil brother has, a cv-cc model can burn a hole in the back of 1/2 metal, make it fall out..
For sheetmetal or thin stuff, my mig is good enough.

[Rustybolt]

make a coupon of what yer going to weld. Weld it up and then beat the holy crap out of it with the biggest hammer you got. If you can't beat it apart, go ahead and weld your stuff.
Bossman welded up a table for a 600 lb vibrating bowl. 2x2x1/8. His idea of being an "expert" is,"Hear that bacon frying sound? That means the weld is penetrating." Dumbass. Anyway one of the legs came off his cart as it was being rolled and almost crushed a little mexican girl. The shop maintenance guy is afraid to move anything the boss welded. Can't say I blame him.

[radkins]

His idea of being an "expert" is,"Hear that bacon frying sound? That means the weld is penetrating." Dumbass.


I agree with your assessment of the "bacon frying sound" when MIG welding. That BS comment seems to be the catch-all phrase when describing what a MIG should sound like when it is working properly and it is said all the time, it is however exactly what you DON'T want to hear when MIG welding! In the first place it has nothing to do with whether or not there is proper penetration but is is the popping and splattering sound of bacon frying what you want to hear? I think not! Instead of popping and splattering what is normal, of course, is a smooth buzzing sound that sounds like, well a MIG welder! :rolleyes:

[Dawai]

Rusty.. I've welded by sound a few times..

We was working in the attic of a buddies shop we put up out of junk pipe... Right there on the secondary tie in welds in the rafters, well the bead on one of the tubes was right next to the crack.. Luckily it was over welded on all the other sides.

Blind people should not weld.. I remember finding the crack the with rod and melting down in it.. Welding by sound.. I was exhausted and standing on a wobbly ladder in the dark frying rods.

I've bent a hook in a rod to weld the backside of pipe when I could not get around to it. Went out side on a job in South Ga.. the mirror was gone off our service truck.. My buddy was laying in a 12" ditch tig welding the back side using the mirror.. Now, that is good.. cause everything goes backwards.. I've tried to cut my own hair.. I remember how easy it was to mess up.. I've used clippers and the scalp to measure it for years now thou.. burr.. plumb to the meat..

[JRouche]

I agree with your assessment of the "bacon frying sound" when MIG welding. That BS comment seems to be the catch-all phrase when describing what a MIG should sound like when it is working properly and it is said all the time, it is however exactly what you DON'T want to hear when MIG welding! In the first place it has nothing to do with whether or not there is proper penetration but is is the popping and splattering sound of bacon frying what you want to hear? I think not! Instead of popping and splattering what is normal, of course, is a smooth buzzing sound that sounds like, well a MIG welder! :rolleyes:

I usually just listen for the sound of my wife screemin, "Hey, yer on fire AGAIN Dumb arss" LOL

Usually, for me if its sounding like bacon, and I mean a full pan of bacon like I like, lots of grease and bubbling I dont have the wire feed up high enough. Just a lil twist on the feed pot and Im back to a nice constant loud buzz. The popping and crackling sound is when its melting the puddle up high and the pool is boiling on top without enough fresh filler being shoved down into the root. JR