Undersized Weld


The weld button/nugget diameter does not meet applicable specifications. (The weld nugget is the fused volume that joins the workpieces. The button is the material remaining attached to the fused area after destructive sheet separation.)


Undersized Weld Figure - Production Engineering


The button diameter is determined by measurement after teardown; nugget diameters may be determined by sectioning the weld. Consult the applicable specification for appropriate measurement method and size requirement.


Quality, Workplace Issues, Cost, Downtime, Maintenance, Throughput (cycle time; PPH), are all potentially affected by this condition. Special considerations are noted below:

  • Quality: Button diameter is the key measure used to control spot weld quality in the plant.

Possible Causes

Strong Possibilities

Weak Possibilities