Most men will realize they can do their first chinup somewhere along the LP when their deadlift gets up into thr mid to high 200s as long as you LP the Lat pulls. Nothing makes Chinups stronger than deadlifts. That's assuming you're not carrying significantly too much bodyfat and turning a 190 lb chinup into a 290 lb chinup.
My gym has an assisted chin/dip machine. Would running an LP on this be better than lat pulldowns, as the movement pattern is closer to the chin up movement?
I have no experience with it personally, but I have never heard that it works. Try it.
I used to think this was nonsense- how could any exercise that didn’t involve bending the arms contribute to chins? Then exactly as mentioned after getting my deadlifts to the high 200’s they went from being stuck for years around 6 reps to 10+. Why did I insist on being ignorant for so long? Gains have slowed again but I guess that is losing some of the novice effect