I was dead wrong about preheating rods on wet jobs

Always thought keeping rods in a heated box on humid days was a waste of electricity... my welder showed me a porosity crack from a Friday afternoon job last summer. He had me strike an arc with a cold rod and a warm rod on the same plate, and I saw it clear as day. You guys using rod ovens on mornings with heavy dew or am I the only one who fought this for years?

2 comments

2 Comments

lewis.terry1mo ago

Honestly, I think you're overthinking it. I've run wet jobs for years with cold rods and never had a porosity issue that wasn't fixable with a quick grind. Those heated boxes just dry the rods out faster, but a few seconds of preheating with the torch does the same thing for way less hassle. Tbh, most guys I know just toss rods in a metal can and call it good.

the_linda1mo agoTop Commenter

Hey man, I gotta push back a bit on that, @lewis.terry. A quick torch preheat only warms the surface, not the whole rod, so you're still pulling moisture from the core into the puddle on the second pass. Plus, that metal can trick only works if you live in a desert - in humid weather, rods can soak up enough moisture in a few hours to give you wormholes that a grinder won't fix. A dedicated rod oven keeps the entire batch at a stable temp, which matters way more for critical work like pressure vessels or code welds.