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3g Weld Test - How to pass

A 3g weld test welded with 7018 is the most common and is often given along with a 4G test.

Scroll down for Dual Shield and GMAW-s 3g tests

A 3G weld test with 7018 stick electrodes is commonly 3/8" thickness with 22.5 degree beveled plates and a 1/4" thick backing strap. Thickness of test plate can also be 1 inch or greater depending on scope of job.

For more videos on passing welding certification tests ... 

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Another Common 3G weld test is Dual shield flux core also known as gas shielded flux core


A 3G weld test using Dual shield flux core also known as gas shielded flux core  is also commonly 3/8" thickness with 22.5 degree beveled plates and a 1/4" thick backing strap

You might also need to know how to pass a 3G mig test


A 3G test using MIG aka Gas Metal Arc Welding could be short circuit mig, or pulse spray mig and is often 3/8" thick plate with 37.5 degree bevels with an open root. 

The root might be downhill or uphill and is usually gapped at around 1/8" root opening.

3g weld tests are sometimes x rayed but are often bend tested by cutting one root bend strap and one face bend strap.

For a bend test, you don't want restarts right on a bend strap

Pro tip:  plan ahead and make any restarts in middle area so that restarts wont be on bend strap areas

bend test

Some best practices for any welding test

  • Review welding codes and standards: Familiarize yourself with the relevant welding codes and standards that apply to the test. These may include codes such as AWS D1.1 (Structural Welding Code - Steel) or ASME Section IX (Welding and Brazing Qualifications).
  • Read and comply with the WPS ( welding procedure specification) 
  • Ask the test supervisor "are there any additional requirements I should know before I start".  Welding inspectors and welding test administrators all have their personal preferences.  Asking this question might give you a little insight into some pet peeve or preference they have.
  • Clean mill scale back at least 1/2" from weld area ..that will help you avoid undercut.
  • Take extra care on the fit up.  Structural welding plate tests per D1.1 usually have a gap requirement of 1/4" +- 1/16".  As far as ensuring penetration on the root pass goes, a wider gap usually helps so I recommend making sure to have a full 1/4" gap that is even from one end to the other.
  • Sometimes there are time limits so plan your work and work methodically. But don't rush. let the piece cool a bit before the cover pass.

good luck welder, 


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