roburrito

I'm building my first frame at a local artisan's co-op. I had planned to TIG weld the frame, but I've sadly discovered that I am out of practice and my skills have gone downhill. Its going to take a lot of practice before I'm comfortable taking my torch to the frame tubes again. Should I just filet braze the frame? Save the TIG for a later frame?

MassiveD

Flipping that around you shouldn't make a frame with unsafe joints, so you have to do what you have to do. Generally FB is the easiest to get a frame out of. Mastery is mastery, and in my opinion the hardest is TIG, then FB, then Lugs, but it does depend a little on what you mean by mastery, lugs include a design element that is not there for the other methods, or you can have lugs that are tigged or FBed, or fabbed from sheet.

The thing to get a safe frame is you have to know when it is safe. So another way to look at it is how are your skill at knowing when you are safe. If you have a welding background, you should know good welds from bad. And really as a past TIGer, it shouldn't be all that tough to get a solid frame going. Pretty is another thing. Bondo is OK if you want a good look, pointless if you are shooting for representative skills. Doug Fattic has reported here that his students who weld take longer to complete their frames than the other methods, but they don't all have any previous experience.

One thing on TIG is that if you don't have a reasonable set-up, I wouldn't even bother. Doesn't have to be state of the art, but without HF, pulse, decent gas coverage, foot pedal, etc... And if you are already uncertain.

Henry III

I can't imagine trying to learn TIG welding and frame building just in the two or three week course he offers. I took the three week course and I barely finished my frame the Saturday morning that I left. I've got a week left of my production welding and finished my TIG welding class two weeks ago but that was a full semester long course.

Do most builder who TIG steel frames just free hand it or walking the cup? My instructor is a die hard walk the cup not to mention he's a CWI also so he's super critical on our welds and everything is to AWS standards.

roburrito

If I'm not worried about it being a skill showpiece, how bad is it to file down an ugly weld and running a new bead on top? My biggest fear is blowing through the tube once the frame is almost complete and having to scrap the entire tubeset.

Henry III

Tig is something you should never have to file or do any prettying upping. Tig is the process that there is usually no clean up work afterwards. Not to mention the bead won't be that big to have enough material to take out in my opinion. Imagine the heat your going to put into that thin piece tubing if you lay another bead down? I guess why risk it is my main question?

Andrew R Stewart 

It sounds like you don't have the time to practice your TIG work in the time you want to finish the frame. In this case I'd advise brass fillet. Andy.

ftwelder

To the OP. Fillet braze. If you do a decent job fitting and wicking in the initial pass it would be easier in my book.

To Henry. Walking the cup is a process that is only used in a very narrow set of circumstances. It's a great skill, practiced by few these days. I started at a place welding machines for processing cryogenic gasses. Everything was pressure tested and cleaned for oxygen service. Big time stuff. I later went into making and fixing airplanes and parts for prototype cars and crazy industrial stuff.

After welding bikes for a few years, I found bike welders to have the highest level of skill on thin material and difficult positioning. Watch the kid at Firefly weld a .8mm wall frame with a few 50 degree mitre angles and you will see. I would place bike welders against anyone and place a bet with confidence.

MassiveD

Yeah, I think he said they spend so much time learning to weld, that they don't attempt a fork, while some of the other builders may.

Walking the cup is basically something you do when you can rest the cup on an acute angle in the joint, and thereby suspend the trode a fairly consistent height above the work. It takes one variable out of play, and is restful, in the literal sense. If you think about a lot of bike tube joints there are normally two accute joints, of different angle and a flat face. It would be hard to get much consistent support.

Bike welding is an art all to itself. If you read much about welding, though, and then you see bike welding it is not exactly code, it has it's own specs, and while a hard nosed instructor would have to be a great asset to a learner, you are going to end up adapting the method a little. Specs like dime overlap, size to thickness ratio, smoothing, etc... are non-typical. Some welders have their own look, and it is a lot more personal than other methods.

roburrito

I spent a few evenings practicing my welds and I'm feeling a lot more confident now. I was just out of practice and it took a little while to get back into the groove of things.

ftwelder

Well, there ya go!