Comments/help needed on this

I agree, I think on your mantlet you should have turned your pencil on its side and almost dry brushed with it. Just getting your graphite on the high points. I'm not sure, I usually only use that technique on the edges of items; I think (my personal opinion) it's often over done. I guess you need to keep experimenting until you find what works for you.

II usually reserve graphite to simulate wear on metal that is very fresh or ongoing, like the bottom of steel wheels on a King Tiger, for example...I think the mantlet look is problematic because exposed steel in that area would patina over very quickly with rust, but not the bright orange kind you often see depicted, but more like a dark, raw umber color...

I normally just use pencils for edges. The final look is nice, but IMHO, way over done. I am not sure if you are just teasting here or if this is actually for a model you are building.

n/a

If you hit them with a filter or a mild flat coat it will tone them down a bit and blend them in.

I think that the mantlet looks especially "not great" primarily because the pattern of chipping is very unrealistic. I can't imagine what would cause a pattern like that. The tool box is a bit overdone as well.

If you're going to chip, it doesn't matter if you use graphite, paint, or real metal shavings; it has to be done with some restraint and realism of it's all for naught.

I use graphite to show metal. On machine gun rings, I rub the shavings of graphite from the lead of pencils where the gun mount turns to show metal against metal. I also use it on return rollers and idler wheels which are without rubber tires. But I always use it as shavings or if not, I rub the dulled lead of a pencil on the surface. I also use it on machine guns and rifles. Better to get shavings from soft- lead pencils.

I think the tool box looks ok. I use a graphite only on the edges to show raw metal.

bob

Frankly, go to a construction site or equipment by the side of some road work and look very carefully and pay attention to what and how and to what degree and where -- weathering occurs on machinery.  Take digital pics of necessary.  Then study these -- and then replicate on your models.  Don't like at other models, look at the real thing (or close to it)

I don't think  graphite looks like metal under paint no matter how it's applied...  Metallic paint looks like metal, and graphite looks like pencils...