Yes normally you would make seperate models for the various armors, weapons, etc. Atthching them to the character model can be tricky however.

There are two main ways to do it, depending on how your character is animated; you can eitehr use vertex animation or skeletal animation.

If you use vertex animation, your best best bet is to animate the pices of armore and weapons along wiht the chracter model in your animation program, and just detach them and export as seprate models--this way the matcgh up perfectly to the character animation.

If your use skeletal animaitons, its a bit simpler, just attach the weapon or armor to a specifc bone or node..

Remebr that in this case, you may want to replace chunks of character model, like insated of putting abreastplate over his chest, just replace the whole chest area...