I was inspecting and cleaning my 2013 Spec Roubaix frame while the wheels are off waiting for tires.
Inside the chainstay near the front I found a scratch that looked bad at first. I checked with a feeler gauge and it is only through the paint.
I bought the bike used a few years ago and have no idea what it went through before I got it but someone said it looked like he tried turning it into a gravel bike, which makes sense. He sold it to me to buy a gravel bike.
Could this have come from the rim rubbing the frame?

Maybe used a tire that was a bit too wide for the frame clearance.

The tire did that.

I wouldn't worry about it, but if it will make you feel better, clean it with acetone and wipe some epoxy into it. Clean the excess off with an acetone wetted rag.

When I bought it I am not sure what size tires it had on it but they didn’t rub. I replaced those with 28mm tires. They don’t rub either.
Could that have come from him running lower pressure for gravel and the tire expanding to the side?

I’m not worried. I was when I first saw it- I thought it looked cut through.

clean the scratch with chemicals.. whip up a small batch of two part epoxy.. dab it into the scratch with a toothpick.. let cure overnight..

Or picked up a rock with the tire

He might have run something bigger before that though.