So I have a department store bike from the 1970s that I picked up a few weeks ago and once I got the quill stem out (using all the tricks I learned from here) I found several gouges on the steerer.

I don’t really understand what they’re from because the gouges are on the outside with dents on the inside of the steerer? Were these caused by over tightening of the quill stem? Also, this is not safe to ride right? It is steel but it’s gouged (with some dents) in several places all around the steerer. Is it fixable at all?

There were so many gouges that I had to number the pictures to keep track of them but I tried to take pictures of the outside and showing the corresponding inside dents.

No idea how they happened, but personally I'd have no problem using a steel steerer like that. Al? probably not. CF? definitely not

Maybe the wedge on the quill was overtightened and stretched the metal causing the tears. And perhaps a previous owner or a mechanic working on that bike peened one of the bulges back inward so it'd slide back into the headset after having to fuss to get it out one time.

All just conjecture and imagination.

the "gouges" are from the original material forming process.... the bike is over 50 years old... the fork is still not cracking.

ride it.

or go dig around at a few Co-op shops for a matching steerer length fork, sand and paint it to match the faded 50 year old paint, then realize you just spent more on the fork than the rest of the bike is worth because of unwarranted fear.

Are the gauges spaced 120* apart? Might be from a 3 jaw lathe chuck if the crown race seat was turned down.
Is the chrome plate intact in the gauges' bases? If so than the "damage" was at the factory most likely. If the chrome is damage/missing in the gauges they likely happened after the factory.
The very first thing I though of was a ball had dropped down and become wedged between the head tube and the steerer. But the gauges from this tend to not be ragged as the ball has no sharp edges.

I tend to agree with maddog34. The only thing I'll add is that I would want to observe the steerer condition every so often, meaning pulling the fork out enough to place eyes on the gauges. That the steerer is essentially hidden from view will mean for some riders it will also be hidden from thinking about it. Andy

As long as it isn't splitting or bulging in the area the stem expander grips, or near the crown race, I wouldn't worry about it.