Spot welding with TIG works very well. Counting works for timing, as suggested by Mblaha. A couple of other things. It is critical that the pieces being welded are clamped tight. Vice grips on both sides of the welds work really well. You can also tell when the weld is done by watching the back side. when the spot glows very bright, its done. (unless you are working with aluminum.) At that point it is close to burn through, so watch it close. Last, I like to set the machine to pannel control instead of remote. That way all you have to do is push the pedel until it fires and count and/or watch, and not be concerned if you pushed it all the way. If you have a timer, they will all look the same.
Done right they really hold well. I have done them mostly on Stainless and thin carbon steels. Aluminum is, from my experinece iffy at best. But I never had a real reason to work it much.
The Happybearwelder.