Ok so I have acquired a TC 2000 that does not have a hole to screw mount a NOD’s bracket. Is it safe to drill one or will it screw it up?

It takes specially designed cutters to drill through Kevalr.  Kevlar liks to just "fuzz" rather than actually cut.  If you do it, best to install a threaded insert (with a flange) using epoxy.  This will reinforce the helmet in teh area of the hole and make installing the mount much easier.

btt

Hi, TC2000.  I guess you were not happy with my earlier answer.  

Perhaps you could contact the helmet manufacturer and ask them to retrofit it with threaded inserts for the mount.  Perhaps they might just supply you the proper inserts for the job and you do the work.

You will not screw it up if you do it correctly.  Part of doing it correctly is have the correct drill bit for the material you are proposing to work.  Special drill bits are made for cutting Kevlar.  Part of doing it correctly is having the proper insert that reinforces the hole you are drilling in the helmet.

You could always just surface mount a stud to the exterior if you didn't want to drill in the shell.

I hope this helps.