fill with mig and finish with tig

[yodie001]

a few questions here:
I am building a set of motorcycle handle bars. There is a joint that has a decent gap that i cant fill with the tig. Can I fill it with the mig then use the tig to get it looking better?

I already tried and I'm getting bubbles in the weld when I tig. But I also just switched out tanks on the mig. Come to find out I got a tank of 100% argon instead of mix...Is this the cause of the bubbles...Ive heard that pure argon is not good for good penetration in mig welds...

[turbo38t]

Argon will create a weak, narrow high profile weld with MIG. You really can't do mig with pure argon unless doing aluminum. Why not make the fitup on your bars betyter then the tig should be no problem. Dave

[yodie001]

If i could do it all over again I would fit the parts better, but its too late now...I've already got about 10 hrs invested in these things.

I guess my question now is how do I fix it?

[MR.57]

If i could do it all over again I would fit the parts better, but its too late now...I've already got about 10 hrs invested in these things.

I guess my question now is how do I fix it?

By starting over and doing it right.

[mikecwik]

how big is the gap? im a awful welder (im even worse at cutting) and have used tig for 3/4 gaps before.

[FusionKing]

a few questions here:
I am building a set of motorcycle handle bars. There is a joint that has a decent gap that i cant fill with the tig. Can I fill it with the mig then use the tig to get it looking better?

I already tried and I'm getting bubbles in the weld when I tig. But I also just switched out tanks on the mig. Come to find out I got a tank of 100% argon instead of mix...Is this the cause of the bubbles...Ive heard that pure argon is not good for good penetration in mig welds...

You raise many an eyebrow with your description of your problems. If you have a "decent" gap that you are unable to fill as a welder then you either need to become better at fitting parts, or take it to a person who can weld better than you.
That person may then tell you you need to do both.
Handlebars is about the last thing a beginner welder should be doing for someone else. That is STEERING dude. A person can loose the brakes and still steer themselves to safety, but a handlebar failure can lead to loss of both sterring AND brakes!!!
On handlebars there should never be a "GAP" unless it is on purpose and there would be little reason for that as well. You should have perfect fit-up with a carefully ground bevel on you parts in most cases.
There is a chance purging could have helped your problem as well....but DUDE we are talking about handlebars here!

[old but new]

Your weld

is only as good as your prep and fit up.


old but new

[kcstott]

In addition to the above suggestions of doing it over.

Let me tell you right now the is no excuse for crap work NONE!!. I don't care how much time you have invested it makes no difference if it's garbage in the end.

refit the parts and do it right. Yes it will add time to the job but it will be done right. I've done more then one job that tried to kick my butt. But I took a little extra time to do it right. And I can sleep at night knowing that each and every one of my welds will hold as designed

[1930case]

If handlebars fail there is a very good chance of getting a pavement facial, and it was infamous back in the day when every hack artist who read a chopper magazine went out to butcher the nearest two-wheeled "victim" he could find.

No motorcycle part is worth an accident, especially some silly custom handlebars that weren't "worth" fitting up correctly in the first place.

Bike modders who do poor work make motorcyclists AND motorcycle mechanics look stupid. The cycle salvage folks do alright without sending them even more wrecks.

[jhaffner]

Side its already posted several times but it can't be said enough. Welders job 75% fitment 25% welding. If you can't fix what you've got cut bait scrap it go to j+p website and order something similar you can customize I ride myself and on a bike is no time to play with poor welding. Not to because critic, its just not safe plus I don't know about the area you live in but customs have to pass a dot inspection to be registered where I live and they are pretty **** picky about those things.

[yodie001]

dang guys...you arent gonna let the safety thing go are you??? This is .120 wall material...just cause the fittment wasnt perfect doesnt mean its not strong...I promise you i could hand the whole bike from these bars...they are stout, VERY VERY stout. I just want to know how I can salvage these bad welds WITHOUT starting over...

I appreciate the concern, but this is my bike and i KNOW it is safe.

[welder_one]

lmao!!! it is what it is... let me first point out that the OP came on to a forum comprised of some of the best welders a fitters around and asks how to weld handlebars on a custom bike with improper and apparently poor fit up, then when the advice rolls in on safety and fit up being a crucial element in any welders job, he proceeds to reject the given advice...hmmmmm......


i can tell ya that the tig will fill gaps easier than mig IMO and prolly a lil better too...

i will also tell ya that if you ridin down roads over by me and lose them handlebars and crash that scooter into a car that has my wife n daughter, you wont ever have to worry about "knowing" how safe you did it... matter of fact, you wont have to worry about insurance or DOT regs either....

this was not said as a threat, just sayin, and there are tons of fellas out that would do much worse than i, my pops bein one of em...


your best bet is to recut and/ or refit the parts as required to achieve proper fit up in order to get good welds. after all, there are societies and organizations in place to regulate proper procedures and joints for welders (aws, asme, etc...) to keep just any tom swingin peter larry or harry that THINKS its a ok joint or its a ok weld from turning his project and other peoples stuff into landfill...

its proper procedure and coding that keeps skyscrapers being skyscrapers and bridges being bridges and not scrap iron that claimed the lives of many... heed the aforementioned advice, you WILL be better off in the long run

[MR.57]

I just want to know how I can salvage these bad welds
\

They're salvageable - scrap steel is at about $190/ton right now.

[seattle smitty]

For a hole you can't, or don't want to, or shouldn't, fill with rod, one remedy is to make a good-fitting filler-patch out of the same tube you're working with.

But the thing people wonder about is whether some or many of rest of the joints were poorly fitted . . . and were they poorly welded? Just because they look good from the outside doesn't mean they are good welds. Motorcycle handlebars and frames, auto and truck chassis and suspension parts, trailers and trailer hitches, these are some things which every self-taught owner of a new Chinese MIG welder (not saying this is you) is eager to work on, but shouldn't until he has had some serious instruction. You're asking a question which would SEEM to indicate that you might not have had this background. That's no crime, but don't discount advice from folks who got early experience by having to cut apart their welds or bend them to failure or look at dye-checks, magnaflux, x-rays, all of which tend to make welders careful and cautious. The insistence by your respondents on "doing it right" is not a mere perfectionist fetish as it may seem to you; in this work there is often a d-d thin line between making a good and a bad weld. Welding joints with fit-ups of varying gaps would challenge the best welders, part of why they are also the best fitters. Yes, fitting is tedious; weld-prep is not fun like working the puddle, but that isn't fun either if you get impatient and are trying to do good work with a bad fit-up. It's common to observe that this trade requires good instruction and lots of practice, but it seems to me that at bottom what a good welder needs to have, or learn (and re-learn frequently, in my case) is patience.

Also, if you're a biker, with biker pals who will want things welded from time to time, don't let them talk you into welding handlebars that have been cracked from a hard landing. Many handlebars are of a strain-hardening alloy, and welding a crack just leaves a disuniformity that can break easily, or so my old instructor taught us.

[Dipsomaniac]

a few questions here:
I am building a set of motorcycle handle bars. There is a joint that has a decent gap that i cant fill with the tig. Can I fill it with the mig then use the tig to get it looking better?

I already tried and I'm getting bubbles in the weld when I tig. But I also just switched out tanks on the mig. Come to find out I got a tank of 100% argon instead of mix...Is this the cause of the bubbles...Ive heard that pure argon is not good for good penetration in mig welds...

Make an insert made of the same tubing and fill the gap...Cheat...