What tool should I use to sand this small part of the visor?

[TheCafeRacer]

Can't seem to get it square.

 

[frb13]

A small file. I got some from napa parts in the bin with the cheap tools.

 

[AFettFullofDollars]

I have a small flat file that I fold sandpaper around. You can usually find them at any hobby store.

 

[superjedi]

I have a set of jewelers files that I use to get into tight corners like these.

 

[SaintHubbins]

Harbor Freight has small jewelers files also

 

[Matty Matt]

Yeah, a small flat file is what you need. If that's not an option, get something flat and square like a paint stick and wrap sandpaper around it.

 

[TheCafeRacer]

Awesome. Just got one today. Working like a charm. Thanks guys

 

[TrevOwnz]

I used a dremel to get most of it and to refine the edge I took something the size of a credit card but 4 or 5 thick and wrapped it in sand paper. This way I had a solid flat edge of sand paper. Worked well for me.