Weld Failure on Radar Arch

[NORO LIM]

On our last trip, the masthead/anchor light stalk fell off our radar arch. The stalk holds the white combination anchor/running light and one of our GPS antennas. The arch and stalk are stainless steel. The weld connecting the two completely failed.

We had the good fortune to be in the presence of two angels of mercy, Patty and Barry on C-Cakes, who were also spending the night at Montague Marine Park. I owe Barry one very nice hose clamp and about 10 feet of electrician's tape.

The next day while looking closely at the arch, I discovered yet another weld that had failed. Here, I hope, are pictures. (If I've blown the attempt to include the pictures, they are in my album - the fourth subalbum.)

Metallurgy is not my strong suit, but these weld failures seem completely unacceptable. The arch is just two years old. Bad luck or bad workmanship?

I assume there is no way to re-weld this break with the wires in place, so I'm in the process of pulling wires, and have discovered only two wires running up to the two-bulb combination anchor/running light. There is a third (ground?) running down from the fixture, but it does not emerge from the now exposed other end of the stalk. Is this thing grounded to the inside of the stalk somehow? Is that standard or acceptable? The housing for the two bulbs also appears pretty cheap. There was quite a bit of corrosion inside the sockets.

I guess I'm looking for suggestions for a better grade of light and wiring, since I'm going to be redoing this thing anyway.

Thanks for any comments or suggestions.

 

[colobear]

Bill,

When I briefly looked at your arch and the failed weld it seemed very clear to me that it was a substandard weld, crystallization, rough metal, etc. The failure was the whole weld pulling loose from the main body of the arch, not a failure within the weld itself. Personally I would really push hard for a complete radar arch replacement including mounting your electronics, especially now that a second weld has failed. You could have been in big trouble had the whole arch failed...very weak radio,no gps, no radar. I know you don't have a manufacturer to seek redress from but now's the time to test whether you CC owners are completely on your own. Good luck and I'm glad the jury rig held.

 

[thataway]

I suspect that there are folks who know who made this Radar Arch--I would then approach the builder of the arch (assuming they are still in business). I agree that this is not acceptable. We have had arches go tens of thousands of miles at sea with zero problems. If the light is a 360 degree light, there will only be a plus and minus 12 volt lead. A single bulb fixture is all that is necessary. Try and find a replacement which is all SS--not pot metal or even combination of brass and other alloys. Hopefully the arch is Stainless, not aluminum.

 

[snal]

It looks like the round tube weld cracked just outside the weld, which I would think is a crystalization problem as someone else mentioned, and the wires would need to be removed for the repair. The other failure looked like a flat bar connection to round tubing, and it wasn't fully welded to begin with.
Although I have a metal farication shop, and I'm NOT a certified welder, the tubing looks to be thin wall, and there seems to be enough weld penetration, so that lends to crystalization.
I used thin wall 1x1 tube for my rack, and checked all welds after our 600 mile TN river trip because the tube was brushed finish, and seemed to have contamination when I was welding...it simply didn't weld right. No failures so far.