Looking For something

Hi,
I'm looking for a cad program to make simple 3d models of metal
structures.
The structures won't be of any great size, only things such as bike
frame, roll cages, etc.
I would like something with pre defines metal's such as flat, round
tube, square and so on, and also do be able to place holes, taped
holes, slots and build the model 3 dimensionally using things such as
bolts, welds and screws.

Is there anything out there that is like this?

Thanks for your help
Mick