Basic Tig

[Peter E]

I'm a hobbyist builder. No plans of ever becoming a proffesional. I don't have an own workshop but I can use the great one we got at work as much as I like. I learnt everything I know about frame building from different frame building forums, including how to fillet braze. Unfortunately we recently decided to let go of our Acetylene/oxygen setup so now I'm left with the Tig welding machine. I can join two pieces of metal with it but that's about it. If I am ever to build a frame using Tig I need to practice, a lot. I realize this will be much tougher than learning how to fillet braze but I'll give it a try.

To get me started, could someone point me in the right directions when it comes to Tig settings for welding a frame, diameter of filling rod, cup size etc.

I got plenty of thin walled tubes and sheet metal of mild steel. Is it a bad idea practicing on mild steel. Will it behave differently to 4130?

What would you recommend me to start practice with?

Thanks!

[Rayburn Shaun]

Practice your technique on whatever scrap you have- start with lap joints on flat stock without filler- that's the absolute easiest weld to learn. Mild steel is fine, just practice- over and over again until they're perfect. Figure in rough terms 1 amp per .001" in thickness to start, using DC for steel. Try using 1/8" thick material for starters, not too thick, not too thin- forgiving and easy.

I'm no pro but I'm sure you'll get good advice here.

[Jonathan]

Agree to all of the above. The is no substitute for using lots of argon. One suggestion, if there is a local TIG framebuilder to you, offer to buy two hours of his time. If it costs you $100 an hour you'll save that and more in practice materials later down the road. It sounds expensive, but its way cheaper to develop proper technique early.

[EnginCycles]

Don't worry about settings in the beginning. Turn it on with DC power, crank up the amperage and start welding with whatever is already on the torch. Getting to the point where you can sit at anyones welder and weld is the goal. This is one of those things that is not really bicycle specific. Head over to the Miller forum and read up. Tons of info and all worth reading. Lots of argon is not the answer to anything. You can easily make turbulence with your cup if the torch is not held right and the SCFM is to high. Plenty of bikes are welded with a #5 cup and a 1/8" tungsten and lots with a #10 or #12 and 1/16" and 3/32" tungsten. Again it is not what makes it work. It is all done by the welder (the person not the machine).

The one thing you can do that will be worth while is get a helmet and call it your own. It is something that is worth the $50 to have a personal feel for the task at hand. I can weld with anyones machine but I really prefer my helmet. It is not anything special but it is mine and I like it!

[Jonathan]

Drew, I don't know if you're referring to my lots of argon comment or not but let me clarify. Lots of argon as in practice a lot is what I meant. Not turn up the argon. There is no substitute for practice. The guys like Zank really set the bar.

[fortyfour]

What Drew said and I'll add this...

When I first started out about 20 years ago, I found the torch, pedal and filler too many things to handle all at once. I was too hot, too slow, too shaky, too uncoordinated. So what I recommend for beginners is this (and if you can get someone who knows what they are doing to show you some tips, that helps tremendously):

1. Eliminate the filler. Get a flat sheet of steel (whatever you can dig up or is on hand). Clean it. Get into the habit of being clean right from the get go.
2. Start by laying down beads sans filler, focus on timing, heat control and pace.
3. Once you feel comfortable with this, now focus on angle of the torch and distance of the tungsten tip in relation to the work piece. Lay down beads.
4. Now you've done this for a while, and feel comfortable with all of the above. NOW add in the filler.
5. Focus on pace in relation to bead spacing, timing, and tungsten tip/torch in relation to the work piece. Lay down lines, upon lines of dimes. When you think you've done enough, do more and then some. All on flat sheet.
6. Now you feel comfortable with torch in hand, filler in the other, timing, bead spacing, heat control and pace. Now join two pieces together. Always have your work space clean, clean, clean. Always have your work pieces clean, clean, clean. I cannot stress cleanliness enough with TIG.
7. Make a sh!t ton of joints, angle joints etc. Make as many as you can. Inspect your work, observe what is right and what is not right. Things will begin to fall into place. It's all practice. Things to think about are bead spacing, uniformity of the beads, no undercutting, smooth transitions, minimizing heat input to name a few. If it looks good, it most likely is good. Shiny, blue or gold/straw is what you want. Dull, gray is not what you want. It takes a while to figure all of this out. Just be patient. You're training your body to have muscle memory and control so you can focus on the weld and not where your hand is or what your foot is doing.
8. If you feel comfortable and confident with all of the above, get yourself some .035 wall thickness 4130 and make a bunch of "T's". Practice tacking them and wrapping welds. Practice makes perfect

And like I said above, patience is key. You will begin to notice small gains over time. Just keep at it, practice and know that it just takes a lot of time behind the torch to get good.

Get yourself your own helmet as Drew recommends. Get yourself a good respirator with replaceable particulate filters (3M makes a bunch). Get yourself a nice set of tig welding gloves (Tillman makes some nice ones). Get your own stainless brush. It's all practice, repetition and being comfortable while welding.

Many times with hood up, I will do a dry run of where my hands with torch and filler need to be. How I'm going to walk the cup or where I'm going to perch a finger or wrist off of. This allows you to experiment with different approaches to (for example) tight spots to get into.

Always clip off a clean tip for your filler. Always let your torch finish it's argon post flow before removing it from the weld site. Always clean your work pieces thoroughly before welding. Never throw in the towel.

[edoz]

In the biz we call that "lots of rod". There's no substitute for burning lots of rod.

[edoz]

As far as the filler goes, take a piece home amd practice feeding it through your fingers. Work it all the way to the emd and start over. Then practice pushing a dime across the table. Do it while you read or watch tv or whatever, until it becomes subconcious.