electrode size?

By joseph schmidt 2 Date 11-08-2010 04:29

I am a student getting ready to take a WABO certification test using the SMAW process.
I was thinking i might try and use a larger electrode, like a 1/4" or 5/16" 7018 insted of the 1/8" that my school has me practice with. I figure i would be able to fill up the 1" mild steel groove weld in as little as 6 or 7 passes insted of 12-15 passes it it would take with the standard 1/8" electrode.

By Blaster (***)

Date 11-08-2010 04:40 Edited 11-08-2010 04:43

If you could do it with 1/4" or 5/16" my hat would be off to you!

Perhaps you may want to try starting with 5/32" instead, we use it all the time. I think that is a very suitable rod for filling 1" plate. You are right, 1/8" is pretty tiny for filling in that application. I would still use 1/8" on the cover pass and root if mixing diameters was an option.

By Lawrence (*****)

Date 11-08-2010 06:12

Blaster covered it pretty well...

Just to reiterate.

Larger electrodes have some limitations in vertical and overhead positions.. More important... Do not attempt to test with an electrode diameter and position that you have not MASTERED in practice.

If your doing a cert test... A WPS should be provided... It will either dictate electrode size or provide a range of electrodes you can use.

Even a 5/32 7018 electrode can be trickly to run vertical, especially if there is even a hint of arc blow.