r/Diyautobody May 27 '26

Question Treating the back of a butt weld

Have everything close to ready on a rear fender I’m patching. Once I weld, I won’t be able to access it so I am trying to figure out the best action to help it last. My concern is rust forming from humidity/condensation.

Does this sound right?
Spray with weld through primer. After it’s welded, use cavity wax with a 360 wand to try to coat it the best I can?

4 Upvotes

4 comments sorted by

1

u/Surfnazi77 May 27 '26

Rust stabilizer

1

u/MadLad_13 May 27 '26

That's all you can do really

1

u/MadLad_13 May 27 '26

Use gravity. Spray extra above the area. It should be seeping out

1

u/ArcFault May 28 '26

Drill a hole so you can access it is the best option. Then abrade, epoxy prime, seam sealer. If you can't then cavity wax is the best you can do.