# Welding in a stainless steel rivet nut into mild steel **URL:** \ **Category:** Welding & Fabrication\ **Created:** [June 6, 2025, 3:00pm UTC](https://fireball.discourse.group/t/welding-in-a-stainless-steel-rivet-nut-into-mild-steel/3640 "2025-06-06T15:00:25Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![wheelz](https://avatars.discourse-cdn.com/v4/letter/w/db5fbb/32.png) [@wheelz](https://fireball.discourse.group/u/wheelz)\ **Post date:** [June 6, 2025, 3:00pm UTC](https://fireball.discourse.group/t/welding-in-a-stainless-steel-rivet-nut-into-mild-steel/3640/1 "2025-06-06T15:00:25Z")
I know this sounds a bit strange but here was my thinking. I welded together a frame with square tube (mild steel) that I will powder coat. I do need to have other pieces that I need to assemble / disassemble with the frame so I’ve been using rivet nuts and fasteners which have worked great. I chose stainless steel for the rivet nuts and fasteners because I didn’t want the powder coating to go into the threads and I didn’t want that to rust while the rest of the frame was good from powder coating. However, I have one location where the rivet nut HAD to go in a very inconvenient place that was the welded seam between two square tube pieces so it partially went through the wall between them as shown here. ![20250605_195334](https://canada1.discourse-cdn.com/flex036/uploads/fireball/original/2X/0/0835b1a63938ddee27f472237b26271e4d70bd38.jpeg) I went ahead an put the 6mm rivet nut in and it’s staying in but probably just from friction with the side walls of the hole I drilled because of where it is. I’m thinking I want to put a little bit of weld to lock it in a bit more. It’s not supporting a ton of weight but it’s 1 of 4 that will be holding up probably 30-50 lbs. I know you’re supposed to use stainless filler but I don’t really want to buy a whole spool and get a whole other tank of shielding gas for just this one rivet nut (haven’t had a need for stainless welding yet, otherwise). My thought is the part I would weld will be powder coated anyway. Does anyone have any advice from those more experienced on what settings to use and what your weld technique would be? It’s in 3/16" thick mild steel square tube, but the rivet nut is a different thickness. Also I don’t want to ruin the threads in the rivet nut so I want to be careful. How would you approach this? Thanks in advance. I really appreciate all the people on here who are willing to share their experience for the less experienced, like me. 🙂 ---
**Author:** ![Fireball\_Jason](https://yyz2.discourse-cdn.com/flex036/user_avatar/fireball.discourse.group/fireball_jason/32/52_2.png) [@Fireball\_Jason](https://fireball.discourse.group/u/Fireball_Jason)\ **Post date:** [June 6, 2025, 5:44pm UTC](https://fireball.discourse.group/t/welding-in-a-stainless-steel-rivet-nut-into-mild-steel/3640/2 "2025-06-06T17:44:17Z")
Mild steel filler can be used. It won’t hurt anything. You won’t be able to tell the difference. ---
**Author:** ![Mark](https://avatars.discourse-cdn.com/v4/letter/m/e9c0ed/32.png) [@Mark](https://fireball.discourse.group/u/Mark)\ **Post date:** [June 15, 2025, 12:24am UTC](https://fireball.discourse.group/t/welding-in-a-stainless-steel-rivet-nut-into-mild-steel/3640/3 "2025-06-15T00:24:34Z")
I would simply solder them in with silver solder ! high strength, simple job and easily flows around the joint.