Chain hitting front derailleur cage with H limit screw fully loosened

Question

I followed the Park Tools guide to set up my gears. The rear derailleur was a success but I can't manage to adjust the front derailleur so that the chain stops grinding on the guard. There's no more give left in the H adjustment so I can't bring it forward. Any ideas?
As you can see by the paint damage, the chain has hit my frame many times in the 6 months I've owned the bike. The chain has never come off though.
One suspicion I have for the chain pushing against the derailleur cage is that the chainring is not fitted correctly, or has shifted. The photos show that it's on an angle. Is this cause for concern?
Thanks in advance.
For the images below, the chainring is set to the top and the casette is set to the bottom:

MaplePanda · Accepted Answer

Are you trying to bring the derailleur farther outwards? If so, you need to add cable tension. Screwing out the H limit screw won’t help if there isn’t enough tension to get to the limit anyways.
To check for chainring problems, derail the chain from the chainrings entirely and give the cranks a spin. If you see the chainrings wiggle side to side, then you know there’s an issue. I suspect your chainrings are permanently riveted to the crankarms, so your only solution would be to replace the entire right crank assembly if there indeed is a problem.
The paint damage on the chainstay is caused by chain slap, where the chain flies up and down as you ride over bumps and subsequently knocks off bits of paint. Although it shouldn’t be a structural issue on a bike of this caliber, it may be best to install a chainstay protector to protect the remaining paint and eliminate all those slapping noises. I find the best solution is a piece of old road bike tire, but if you don’t have one then anything from adhesive vinyl wrapping film to neoprene sleeves to molded rubber guards are available commercially.
The scratches, gouges, and chips directly beside the middle and small chainrings are more mysterious. I’m not sure what causes them (frame flex?), and I have experienced these symptoms on both of my bikes even though their drivetrains are set up very well.

Andrew Henle · Answer

There's more to front derailleur adjustment than limit screws and cable tension.  Both the angle of the derailleur and the height need to be set properly.
The angle of the derailleur being off can cause chain rub against the cage.  If the rear of the cage is angled too far outward, the chain can rub against the inside of the cage when the chain is on the largest cogs.  If the derailleur is angled so the the rear of the cage is too close, the chain can rub against the outside of the cage in gear combinations where the chain is on the small cogs.
The derailleur looks to be canted slightly inwards towards the rear.
When looking down on it, I'd say it needs to be rotated counterclockwise to move the rear of the cage just a bit farther from the frame.
And that will likely affect the limit screw and cable tension settings.

Chain hitting front derailleur cage with H limit screw fully loosened

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