Welding Tips and Tricks

Can I tig weld tungsten? A guy that balances crankshafts wants me to weld the "heavy metal" into the crank. Also known as "Mallory metal" The slug is pressed into the cheek of the counterweight. The slug is not in the radius of the counterweight to where rotational forces would act to throw it out. It is pressed in but he wants a bead "just to be sure"
Any thoughts?

not really, it is a usually a tack/bead on the crank material to prevent the mallory from falling/slipping out. The mallory is contained not welded to the crankshaft.
a quick bead tack, do not linger to prevent heat/warpage/stress
Of course a minor rebalance check after weld.