Published on 11/04/2026 · by Leandro Caldas, glazier, founder of Routeck and creator of the Arena
MIG welding a mirror frame: starting out if you have never welded
MIG welding a mirror frame is what the round put in front of two glaziers in the Arena do Vidro final. The challenge was a mirror with a metal frame that could stand up on its own, in 60 minutes. And the first scene of the round says it all: almost nobody there was comfortable with that machine.
I have already written about what the final teaches about welding in general. This post is about another stretch of the episode: the first minutes on the machine, the moment the metalworker comes in and the first opinion on the work. The full episode is in the video above.
The first time MIG welding a mirror frame
When he was asked if he had ever welded, the answer was: with this one, never, only stick, and he did not even know how to use it. On the other side, Rômulo had never welded either and was calm about it. The comment at the time was that they had put one of the best machines in his hands, that you just pull the trigger and weld, and that he had understood that.
That was on purpose. The idea of the Arena is to take glaziers out of their comfort zone and make them face what they have never done. People who work with mirrors know how to measure, how to plan and what the customer wants. What is missing is picking up the machine and burning that first piece of metal, and that only comes from doing it.
Ten minutes of a metalworker: who to call and when
Ten minutes into the round came the rule: from then on each of them could call Rui or Peterson, two metalwork specialists, for ten minutes of hands-on help. Sanding, welding, whatever was needed, at any moment. Whoever called first got to choose.
The first to ask for help made the reason clear: nothing had gone wrong, he just wanted one more idea to solve it. And he chose Peterson. Asking for help there was not weakness, it was strategy. It is the same in a glass shop: a good metalworker for ten minutes at the right moment beats an hour trying alone.
Where to start on the structure
The first point raised was the order of the work. The idea was good, but the opinion on the spot was to have started with the thin flat bar, putting it on earlier to move faster. Notice the detail: this is not about the weld bead, it is about the order you build the piece in.
- Before you turn the machine on, draw what is structure and what is finish.
- Choose the metal by what it has to hold: standing up, the weight of the mirror counts.
- Keep a scrap of metal to practice your first bead before you touch the frame.
- If there is a metalworker nearby, have him look at the plan at the start, not only when something went wrong.
What to take back to your glass shop
If you sell mirrors and want metal frames in your catalog, there are two paths: learn to weld or work with a metalworker. The final showed that both work, as long as the glazier shows up with the plan ready.
- Can someone who has never welded make a metal mirror frame?
- In the Arena do Vidro final, a glazier who had never used that machine made the frame within the 60 minutes, with a plan and ten minutes of help from a metalworker.
- Is it better to call a metalworker than to learn to weld?
- Often yes, especially at the start. What matters is bringing the project ready, so you make good use of his time.
- Where do I start on a metal frame?
- With the plan: what is structure and what is finish. In the round, the opinion on the spot was about the order for placing the flat bar.
Want to talk about metal frames? Message me on WhatsApp at +55 31 9095-8383.
Full episode 4 · MIG welding for beginners: what the final showed · How to plan a framed mirror before cutting metal
