Welding Hardtail

OK, there are alot of people here who are a little bit misconstrued.

You CAN weld that frame just fine with a 135 Amp machine. I've built several roll cages and rock crawler chassis with just the same machine when I was yuounger. I own a 180 Now, and a 200 Amp TIG, but that 135 is always on standby. That said, the frames and chassis's and roll cages took major beatings and never once did we have a weld failure from using the small machines. Mutliple rolls, drop offs, crashes, etc...
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Usually figure on 1 amp per .001" of material thickness for a single pass. So on these frames, you might have .125 tubing, needing about 125 Amps.

I ALWAYS weld with .025 wire, .030 gets too nasty for me and I don't like the amount of filler it requires. I like to use gas, but with flux core, using the .035 is just fine. With flux I like to weld HOT and use a slower wire speed.


Don't listen to all these guys that say your hardtail will fall off. It WON'T :thumbsup: you might get a broken weld if you weld it extremely cold and get ZERO penetration, but that would be obvious. And it would take 5 or more weld to brake completely for the tail to "Fall Off" and you should keep an eye on ANY hardtailed frame for cracks and failures throughout the riding season...


This ENTIRE rig was built with a 135 Amp MIG, on Flux Core wire, outside in poor weather. It was barrel rolled several times, flopped once and slid down the road on the freeway, rolled over backwards, and beat off of every tree and rock on the South. No weld failures, but plenty of dented tubes. :laugh:

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A 135 will weld up that hardtail no problem, and fluxcore works fine too. You can get better penetration with flux, but it also takes more know-how. Building a crawler is entirely different than a first-timer welding on a prefabbed hardtail. Look at the amount of "over-building" that you've put into that crawler. On top of that you obviously have plenty of experience. It seems a little irresponsible to encourage someone who obviously doesn't know what the fuck he's doing.

It may take 5 welds breaking for the tail to "fall off" but it only takes 1 weld breaking to cause enough flex in the frame to kill someone on a fucking motorcycle. Less steel = WAY more flex and way more stress on every weld. Big difference between sitting with your ass in the wind on 2 wheels at 70mph and being completely enclosed in a steel cage at low speed.
 
Ok maybe I was exaggerating a bit when I said the hardtail would fall off :laugh:. But I was trying to make a point that he should have a welder do this part for him. And as far as welding with a 135amp, sure it can be done no problem by someone who knows what they are doing! But you can have pretty welds without good penetration and how would you know without experience? With 120wall a 135amp is close to it's limits and a newbie is not going to bevel, root pass or anything but stick it together. Go ahead and do it! What's the worst that can happen? :D (possible HAZ issue?)

P.S. Hugh, You know how to weld, does he? Just trying to keep him alive :bike:
 
I understand everyones points. BUT, how else is someone going to learn? I see some of the worst booger snotted shite that comes through my shop that has been holding of for over 30 years, so if he tosses down a few beads and puts up some pics, I'm sure we can give him a "Yea" or a "Nay" on whether it would hold together.

Go get some practice on similar materials/tubing and post up some pics. No need to be a pain in anyones rump here, I was just trying to encourage him to learn and give it a shot.

And yes, I have ridden on cracked frames and such on a motorcycle. Its a loose ride for sure :) Some have only had Bondo and sheet metal holding them together... Thats scary...


(And I'll be the Devils Advocate here :devil:) Its a TCBros tail afterall, and the welds I've seen on those things aren't exactly rocket science. Some I've seen don't even have the welds completely finished around a tube :yikes: For that matter, some of the ugliest and coldest welds I see are from the factory. I know it is over engineered, but those welds look hideous sometimes.
 
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Not a good idea to be doing welds on a frame with a new welding outfit with minimal performance or knowledge of the welding machines performance. Why would anyone do multiple passes on a .125 wall instead of going to a welder with plenty of power to do the job in one pass? That is nuts! Learn on something that doesn't involve a possible loss of life or injury. I wouldn't weld that tube without a tube inside it anyway to join the two parts.
 
It's a smart idea to fit a smaller piece of tube inside to 'gussett' the weld & BIG bevels, if the weld fails you will see a crack, instead of it just dropping off.
 
just clean your metal really good rubicon and ill be sure and include you in my prayers tonight.

I did a tc bro's in june they include slugs...he should be fine he has " grown balls".


and teebs is exactly correct.I could not have said it better myself.
 
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Teebs said:
I'll just say straight out that you're acting like a fucking idiot.

If you had dick-all experience with a welder you wouldn't need to be asking these VERY basic questions and then get your panties in a twist when guys that obviously know a fuck-ton more than you suggest that you not be a total moron.

You should really use .023 and go gasless. That would be super sweet!!! (That was sarcasm, if you didn't catch it.)
Click to expand...

Get em teebs bout time you had something construtive to say. Haha, JK old man But really who picks there first weld on a potentaly life ending situation.
 
wow...ok so i am thinking about doing the same thing. i picked up a welder and would like to build a hardtail from scratch and weld it onto my frame. i have been doing the same thing, asking all the questions, and to me it seems like it IS possible to do but you need to be cautious. everyone says practice, practice, practice. so after all the practice and the advise given by the pros, would it not be justifyable to try?

now once it is all together and welded up "strong" is it possible and wouldnt it be adviseable to have it checked by a professional welder to give the OK???

what i am trying to say is if he and i get the right instructions and advice, practice, weld it properly and then have it checked by a pro wouldnt that pretty much eliminate any probability of failure? i am sure there is always a risk involved but then again isnt using a 30 to 60 year old frame that has been sitting in a field for 20 plus years a lil dangerous too?

i am a firm believer that i can do anything anyone else does and maybe even better than they can (i will put more time and effort into it if its mine). i just think if you do your research, follow instructions to the T and check it over, you can do anything...
 
I don't know guys. I have never welded, but I think it's great to want to do it yourself, but I would start practicing on things that aren't such a hazard to your health if you fuck it up.
 
It takes about ten years to get really good at something. You'll find that consistently.
 
It doesn't mean you suck now. But it means you'll be better when you're 39 :)

Seriously though, this applies to trades, to languages, musical instruments, the ten years is very consistent for some reason. That's when you hit your stride.
 
I don't think these responses are to deter the "do it yourself" or even to say that is "HAS" to be done by a professional.

Now... Hugh and others are right. Can it be done? Yes. That is "IF" you know what you are doing. Its all about penetration... I have seen little welders do a great job at stuff like this, and I have seen $1000+ welders do a shit job due to the operator.

I think the factor here is the way the questions were brought up. Jumping in and asking what appear to be newbie questions, give off the "I'm new to this".

Practice, practice, and practice is great, assuming that you are doing it right in the first place. There will always be a debate about topics like this no matter what is said....
 
XJWMX- If you havn't got it nailed within 3 years go do something else, anyway, who would employ you for 10 years while you are still leaning, except, maybe NASA.
 
You should be able to handle junior duties in three years. It takes ten years to get promoted to senior, unless you have a PhD or went to Harvard, but that's a different universal phenomenon....
 
The hard part of marriage takes about ten years. The part where you have to reconcile what you've done to yourself.

Back to welding now. Just making an observation. Not trying to jack the thread.
 
thanks guys for your imput, i welded for 2 years for a company that made heavy lifting elevators. i have not welded in about 5 years whats why i had a few questions doing it on a budget ie. doing it myself. i know to take the time and make sure its safe im not just some red neck doing this. i am in the air force working on aircraft and i know all about inspections and quality control. i was just looking for some tips of people that welded frames on there self not by people that didnt weld a hardtail on and just wanted to put there 2 cents in. thanks to the people with positive feedback
 

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