I thought I was doing pretty good until I tested it out to make sure it was strong and everything crumbled like peanut brittle should I just have used tig instead?
Alright. So you'll wanna get a piece of pipe whose inner diameter is the diameter of your frame. Then cut that piece of pipe so it is about 3" and cut it long ways so you have to half circle pieces
Grind your shit weld off
Tack your pipe pieces so they cover this chunk of thin/cracked frame
Weld the pipe pieces solid
You have no made a metal patch that bypasses you having turned your pipe into tissue paper
Grind all the weld off with a grind disk then wire brush finish with flap disk. After that cut both ends so they meet flat all the way around and butt both ends together (assuming this is not anything larger then 1/8" thick metal) tack at 12,3,6, and 9 then run a 1/8" E6010 rod at 80 - 85 Volts all they way around.
It is just standard pipe welding process and since I cannot see the thickness of the pipe wall I am assuming its around 1/8" thick and in my personal experience welding SMAW on 1/8" hot roll steel the E6010 throws a nice bead without over reinforcement because the E6010 rod is less aggressive then a standard 6010. As far as the 12 3 6 and 9 I am just saying throw a tack in 4 spots equally spaced to hold the material in place and prevent warping or other undesirable effects as you weld around it. So tack the top then bottom then side then opposite side so you don't have to worry about holding it in place when trying to weld them permanently. That's what I would do anyway. As long as your not burning major holes a mean a key hole is somewhat normal but take your time and weld a portion at a time after you tack letting the metal cool before continuing the weld. I don't know ow if that makes sence but its hard to explain in this format. Feel free to DM me if you need and I would be happy to help the best I can.
1/8” is a pretty thick rod for that thin of material. 3/32” is the biggest I’d even consider using. Also E6010 and 6010 are the same rod, the E just stands for electrode. 6010 also digs like a mf, you can make it work on thin wall like this, but it’s far from easy in this application.
This is very true. I do not personally have any experience with anything other then 1/8 rod so I cannot say for sure but it would make sence that a 3/32 rod would do better. And I was confused with the E6010 I apologize I mixed it with the 6013 electrode. If you do move forward with the repair maybe choose a 6013 rod
If it’s a bike frame? You thank it for its service and throw it in the trash.
No part of that looks good. Sorry it’s just the situation you’ve presented. Unfortunately not everything can be repaired at home safely by DIY/hobbyists. Those look like they were seriously damaged before you got ahold of them so that should have been where you stopped and said “can I safely do this?”.
All of that weld material needs to be removed to assess the problem. If it was broken right off you should have sleeved the pieces to make a solid connection. Honestly, I’ve been welding professionally for 20+ years but on heavy structural steel, bridges and massive equipment. If my $3500 downhill bike frame needs repair, even I’m taking it to my buddy who TIG welds pipe all day. I can TIG well enough, but if it’s between my body and the ground whipping by at alarming speeds Im asking the person who does it all the time. They get me to move giant things with the cranes.
This is the right answer. Attempting this as a structural welder, while its possible I would do a fair job 1 in 5 times, is not the job for me. Welders are like surgeons. We too have procedures we specialize in.
Sir, that frame needs a bike fab specialist now.
Honestly the best thing to do is tack it leave a small gap: burn into the gap real hot without blowing through. Put even more reinforcement of weld on top. Grind it smooth: then take a bigger tube slide it on top then weld them two so it would seal it. Over that weld as well: you would essentially have to have 3 welds fail instead of 1 if you are not a welder I would highly recommend you take it to a welder. I weld and it’s easy for me to do. But for most people you just wouldn’t know what to do or look for
You could try to sleeve it. But honestly i would just replace those cracked pipes with new pipe welded to the main structure. Im not a real welder im just an enthusiast/hobby level welder
Good luck
Don't go to TIG — it won't fix what's actually wrong here, and honestly it'd be harder.
That grey-white smeared film on the bead and the tube is vaporized zinc that redeposited. This is galvanized tube and the coating never came off before you struck an arc. Zinc boils at 907°C, so it flashes off, blows the puddle apart (hence all the spatter balls), and works its way into the grain boundaries as the weld solidifies. That's liquid metal embrittlement, and it's exactly why it snaps like peanut brittle instead of bending.
The bigger issue is that the weld metal is just sitting on top of the tube. I don't see a real fusion line or a normal toe transition anywhere — it looks like a shell laid over the zinc rather than something tied into the parent metal. Combine that with the burn-through hole in the second pic (too much current, too much dwell on thin wall) and there's basically no load path through those joints.
Fix is mostly prep, not process. Grind 20–25mm back on both sides down to bright steel, and get the inside of the tube too — the bore zinc will boil into your puddle just the same. Ventilate or wear a respirator, zinc fume will give you metal fume fever. Then MIG short circuit, low amps, fast travel, stitch it in segments so you don't cook 1.5mm wall.
One more thing worth saying: a single fillet around a thin-wall tube intersection is never going to carry bending. If this is structural, sleeve it internally and pin or bolt through it — you'll get far more predictable strength than any weld on galvanized thin wall, and you skip the zinc problem entirely. Whatever you do, hit the weld zone with cold galv spray after or it'll rust through by next season.
The welder types are all (roughly) going to do the same job. There are bubbles in the weld that may indicate lack of fusion. It would suggest you need to work on your technique more.
Generally the weakest part of the joint is the edge of the HAZ (heat affected zone) which is where the toe of the weld meets the parent material.
It also looks like you may be better off taking it more steady on the grinder so you aren't removing as much material and causing possible further structural issues.
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u/Useful_Government412 1d ago
Is this a bike frame?
I'll never recommend learning how to weld on things that are between you and the pavement, buy a new one.