Ugly welds that aren't necessarily rejectable can be a platform for teachable moments.

Having quality workmanship samples prominantly placed is a good way to illustrate expectations as far as cosmetics.

Make some lovely welds, make some ugly welds, make some rejectable welds.. shoot them with clear coat and place them on the wall as a contrast.

An example of a critique of an ugly weld might be something like this:

"A 1/4" fillet weld with just one leg oversized by 1/16 inch will increase weld volume by 25%.  Then break down how much that costs in filler metal and time over a year.  It's a real eye opener.

"A weldment that requires 5/16" fillets that is produced with 3/8" welds is an increas of 44% in weld volume..... Just an extra 1/16 per leg."

"A weldment that requires 3/16 and is produced with 1/4 inch welds is a 77% increase in weld metal volume.."

If the welds exhibit excessive convexity this increases weld metal volume even more. Not to mention the increased stress at the toes of the weld

Examples drawn from the Certified Welding Superviosrs Manual for Quality and Productivity Improvement.

That would fall under workmanship.

commentary C-5.1 The criteria contained in clause 5, are intended to provide definition to the producer, supervisor, engineer and welder of what constitutes good workmanship during fabrication and erection. Compliance with the criteria is achievable and expected.

Therefore, clause 5 (chapter 5) unless modified by contracts is a requirement inspectors should know. If the workmanship concern is not specifically prohibited (groove angle prep figure 5.3, gouge or notch limitations para 5.15.4.4, 5.18.4 additional tack weld requirements, 5.22 tolerance of joint dimensions fig 5.4 etc) Then the weld should be accepted.

Therefore to answer your question, there is no criteria in D1.1 2008 or any other year I am aware of for "ugly" and therefore I don't reject it without a specific criteria in writing from which to assess it for acceptance or rejection.

Regards,
Gerald