foot filing how to stop going too far

[1moreRep]

Hi, That's it really- how can I file without going too deep- how often do you stop and check sort of thing?

I don't think you can go too far. The file only really takes off hard skin. Once you are through to soft stuff the debris becomes more like pencil rubbings rather than powder. As long as you are just filing it'll be fine. You do need to be more careful with a corn plane as you can cut yourself .