right now I have a rather basic set-up, dynasty 200 with an argon tank. my main use is building steel bicycles. I'd like to make the jump into titanium so I need to get set-up for the internal purge necessary. should I buy another tank? or a fancy dual flow rate regulator? what's the recommended set-up for a dude in his garage who wants to weld titanium?
also, is there much of a learning curve moving from steel to titanium? what would be the most economical way to learn to TIG titanium?
Welding titanium is a breeze. It melts easily and smoothly, much like stainless steel.
It is the purging that is the difficult part.
A few things you will need are some large #3 wide gas lenses with #12 cups. These make excellent purge jets for purging air from around the outside of your joints. Silver solder or TIG braze some small hose fittings onto the threaded end so they can be hooked up to a hose.
Make a small manifold using brass 1/8" pipe fittings. You will need to be able to turn 1 valve to turn on the gas to the manifold, and the manifold should have at least 3 outlets that have individual valves on them.
It means maybe $30 in brass fittings in a hardware store. I like 1/4" acrylic hose for my purge lines.
Get some foil tape from a hardware store. It is what is really used for sealing air ducts, not "duck" tape. A little pricey, but it takes good heat and is great for keeping purge jets in place and for sealing holes in the frame tubes temporarily.
For feeding the purge system, you can use either a separate tank and flow gauge, or a dual-flow-tube flow guage, or a splitter on your tank so you can mount 2 flow gauges on the same tank.
The dual tube gauges show up on ebay for about $75. I built one by simply adding a second flow tube to a good smith flow gauge.
For the torch, you will want a CK Worldwide Extra wide gas-saver gas lens. It is a special gas lens just for titanium work. It produces a jet of gas about 1.5" in diameter. The cup is pryex glass. I have one and it works very well for open joints. You can extend the tungsten up to 1.25" past he edge of the gas cup. You can use standard gas lenses as long as you have enough side jets to keep the weld area purged. You can affix an extra gas jet so it shields the area just behind the cup on the torch. This is called a trailing shield.
Purging the inside is quite easy. You will needs some corks that will fit in your tubes. The corks should have small tubes poked through them so the gas doesn't free flow out the tubes.
You feed the gas in one tube and it will bleed out the others.
You will need filler rod that matches your base metal as close as possible.
With titanium, you are allowed a little straw color , but no brown or blue, and if you see yellow dust on the backside, then it is a screwed weld.
Run your amperages the same as Stainless steel.
2/3 of an amp per 0.001" of thickness.
You can check out the links to purge stuff on my links list
--What he said. And if you're doing small stuff build yourself a tank and do your welding in there. I've got photos of the one I made on my welding page.
PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.