Ti tubing PRACTICE welding tips

[afwalker]

Looking for suggestions on welding Ti tubing practice joints. Tig dynasty dx and I have 16 feet of 0.035" 1" and 3/4" tube to cut up and weld on.
Sticky stuff compared to steel and stainless. What I'm wondering is knowing it needs to be super clean do I:
A) need to ultrasonic clean and if so with what cleaner?
B) how much back purge flow is needed? 5cfm 10,20?
C) welder settings: no pulse, or pulse with what background/peak/rate etc. Amps, lanthanated tungsten 2% is what I have

This is for practice welding, not planning a bike until I can get a mentor/class arranged
thanksoriginal.JPG

[afwalker]

hmm, also have 8' .051 3/2.5 1" for practice
and files/hole saws/emory only used for ti...
mentors?
any builders consider a weekend seminar/class gig?

[Jamie Medeiros]

A. You don't need an ultrasonic cleaner, brush with non-woven abrasive inside and out then clean with water and simple green or dish soap (dawn works great) rinse and dry. Don't touch afterward with oily hands. Tube should be shiny and free of the gray oxide layer. Some people rinse with acetone after but I find the more you do to the tubes the greater chance for oil to show back up. Plus acetone isn't good for you or the environment.

B. Back purge flow depends on how sealed the tubes are. I usually run 20cfm tacking chainstays and 40 for tacking whole frames. Too much and you can venturi air in.

C. Around 70 amps no pulse, ceriated tungsten is what we use but I hear the lanthanated works too.