Aluminum Welds on Boat Trailer

[Silent_Warrior]

First off I am a beginner, although highly intelligent and capable. Go easy on me. I have a bay boat that sits on an aluminum trailer. The welds on the trailer or starting to get stress fractures. I have a Hobart 210 welder. Will purchase he ancillary spoolgun to weld aluminum. Aluminum is very thick, although the welder should be capable with 220V. Options I see to fix are as such. Please let me know which is best.
1. Grind welds completely and completely re-weld
2. Weld over stress fractures
3. Grind off the fractured weld, keep good weld portions and re-weld what was grinded.
3. Bring it to a professional which negates the purpose of me purchasing the welding machine

[Ant_j]

Just my own personal advice, I think tig welding is better than spool gun. But you have a spool gun, if the welding is on the bottom, I think all the grinding is unnecessary, penetration is more important (no leaks). Aluminum is my favorite to weld on. Take scrap and get your gun set right before you weld on boat.

[Dale M.]

Any cracking is going to have contamination (corrosion) in them, prudent thing would be to clean them by grinding area to weld.... I am finding with most of my welding prepping area properly only improves weld quality...

Dale

[Dale M.]

Just my own personal advice, I think tig welding is better than spool gun. But you have a spool gun, if the welding is on the bottom, I think all the grinding is unnecessary, penetration is more important (no leaks). Aluminum is my favorite to weld on. Take scrap and get your gun set right before you weld on boat.

But he does not have spool gun...YET...

Dale