Technical Sealing a ground bond

Thanks for the info on the 309L. I had always thought that dissimilar metals could not be welded - learn something new every day! Filed for future reference.
Don

 

Have wanted to do it on aircraft, never had the opportunity.

 

A thin coat of varnish will protect the contact from corrosion. It is clear so no one will see it. A star washer will be sufficient, but a flat washer with a split lock washer on top will be better.

 

Depending on the grade of SST, it is not really that dissimilar to steel, they still have approx 70% iron or more. Many of the same alloying elements in stainless also exist in various grades of steels.

If you don't use the recommended alloy filler rod, you just create a different alloy in the weld Zone. That can be a problem if you need specific corrosion properties or operation in unusual environments. But for a ground stud, you will never know the difference.


Sent from my iPhone using The H.A.M.B. mobile app

 

\
The restroom is 'Traditional"..........on a lightly populated aircraft, a seat in a vacant area will do......

 

Its best to choose a rod that has some engineering data to substantiate a likelihood of success.

There is plenty of data out there on using 309 for welding stainless steel to carbon...

Actually I do not believe that 309 is ever a wrong choice.

It would be a real bitch on your drive time if this was a ground stud.


Besides, it's over complicated.
Drill a hole and tap it, (back it up with a nut if you want to be fancy) bolt down the ground lug. Use star washers to cut the coating if you think copying the OEM engineering is good. No welding needed. No shop floor metallurgy and no breakdown from missing ground.

 

Agreed. Always best to use the correct filler.

I would say that having a bigger fillet would help in cracks like that though.

Nice looking welds! What machine do you have?



Sent from my iPhone using The H.A.M.B. mobile app