Debate: When a welder told me my fit-up was too tight, I fought him on it

Had this old timer on a boiler job in Gary, Indiana last fall. He watched me spend an hour getting my root gap perfect at 1/8 inch, then said I was wasting time. He insisted on a 3/16 gap and a hot pass that would burn through anything. I told him no, that his way would drop slag every time. We ran a test piece his way and it held pressure fine with way less cleanup. But then I tried it on a different joint with thicker plate and got burn-through bad. So now I'm split. Do you stick with tight gaps for control or open them up for speed? I've seen journeymen argue both sides and it feels like it depends on the metal thickness and position. What's your take when the blueprint doesn't specify?

2 comments

2 Comments

claire_butler18d ago

Is nobody gonna mention that the real variable here might be your prep work and bevel angle, not just the gap size? A 30 degree bevel with a tight gap is a completely different animal than a 45 degree with a wider one.

lucas_perez8d ago

Nah, I gotta disagree here @claire_butler1. Idk, in my experience gap size is way more important than bevel angle for most welders, especially on thinner material where even a tiny change in gap can mess up your puddle control. Maybe it's just me, but I've seen guys nail 45 degree bevels with big gaps come out better than folks who obsess over a perfect 30 with a tight gap.