TIG Handbook Mistake?

[aphexafx]

This probably doesn't deserve a whole thread, but I couldn't find a good place in any existing threads to put it.

Can someone explain to me why, in Miller's "TIG Handbook", page 6, Figure 2.2, the diagram shows current flowing from the positive side of the voltage source, through the TIG torch (which is hooked up backwards, DCEP), and then returning to the voltage source at the negative side? Is this a mistake or am I confused?

"Current" refers to the movement of electrons, which are negatively charged, towards a positively charged sink, right? So as far as I can tell, the diagram is fine, except that the "+" and "-" signs are reversed. Right?

[aphexafx]

OK, then... (I'm re-reading my TIG Handbook, if you can't tell, and these are things that bothered me the first time though...)

We're in the "TIG Welding Handbook" again, page 7 now, Figure 2.4. This illustration shows sine wave representations which, independently, are fine. But since they are shown next to each other, it appears that they are backwards. The 50 Hz waveform is dimensionally smaller than the 60 Hz wave. Since 60 Hz (1/60 second) is a faster cycle, it should be represented as the more compressed waveform (the top one), while the 50 Hz (1/50 second) should be represented as the longer wave (the bottom one).

Again it looks like it's just another labeling mishap. Yeah?

I'm just nitpicking. This handbook is probably the best modern short course in ALL THINGS TIG ever compiled (at least of the ones that I've read). Although it is, understandably, Miller-centric.

But Miller should fix these bugs!

[dyn88]

I do believe that the illustrations are reference only. Just to clear this up though you can tig weld with dcep or dcen depending upon the thickness of the base and the heat input desired.

[Rocky D]

I do believe that the illustrations are reference only. Just to clear this up though you can tig weld with dcep or dcen depending upon the thickness of the base and the heat input desired.

In what instance would, or could you use DCEP in TIG????

[fun4now]

magnesiom

........................

yep they did the sine wave backwerds. lol i was scratching my head over that 1 also, then just decided to let it go as a typo

[dyn88]

Dcep would be used to weld thin materials where burn off is unacceptable. In other words if your heat input needs to be less than the available low of the machine.