Mystery tiny dent

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I have a bunch of these in the exact same area on both sides on my 14. Just chalked it up to some kind of manufacturing phenomena. I'll bet if some other members look close enough more will notice the same...
 
All of us have the dents. Some are more visible than others. I didn't notice mine until I saw another post asking about the dents.

The dents are actually a result of a manufacturing process called resistance spot-welding. It's a process in which contacting metal surfaces are joined by the heat obtained from resistance to electric current. You can demonstrate this denting phenomenon by placing a drop of glue in the center of a piece of paper then place another sheet of paper on top of the sheet with the glue drop - let dry then gently pull the sheets apart and notice the dent.

You might have seen a TV video showing an auto manufacturing line with robots clamping down on a car body and sparks flying - that's resistance spot-welding in motion.

In the show room the dents are probably not visible but after a few miles, sun, heating, cooling, the metals joined by the spot-weld tend to move leaving the dent like the "paper dent." It's probably more an esthetics problem rather than a manufacturing defect.
 
I went ahead and watched the CX5 Assembly video again on youtube. Thought maybe I could see if there was a place during the construction process that I could pick up on it, but I could not see one myself.

here is the assembly plant video, fun to watch...
 
I went ahead and watched the CX5 Assembly video again on youtube. Thought maybe I could see if there was a place during the construction process that I could pick up on it, but I could not see one myself.

here is the assembly plant video, fun to watch...
That was a good watch, thanks.
 
⋯ In the show room the dents are probably not visible but after a few miles, sun, heating, cooling, the metals joined by the spot-weld tend to move leaving the dent like the "paper dent." It's probably more an esthetics problem rather than a manufacturing defect.
Two things here.

Firstly, if these tiny dents which appear to the same roof rail area above the rear doors are caused by spot-weld, from my past experience seeing the assembly line those spot-weld points need special treatment if they're on the visible part of sheet metal for cosmetic reason. They're to be smoothed out even with filler if necessary.

Secondly, there're many spot-weld points have to be done to the visible part of sheet metal such as any connection point between two body panels. So why we don't see these tiny dents in other areas such as the roof rail area above the front doors, top of the A、B、and D pillars?

I also believe these tiny dents are caused by spot-weld but it seems Mazda overlooked this particular area for special treatment, or they think these dents are acceptable with their esthetic standard.
 
can't find those dents on mine - hope it's not because the roof rails are blocking them from sight...
 
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