This Ballista (crossbow) is prints in place, the only extra part needed is a wire which works as bowstring. 

I used four layers of cotton sewing thread as bowstring!

NOTE: I would recommend at least 90% infill.

You can print this in PLA or PETG.

I made a change at the original model, I extruded a surface and after that I made a 5 mm diameter hole that works as a key ring.

I think that a model like this could be very nice to attach to a backpack for example and to do this you need to have a modification like the one I made.

All credit goes to Chipmunk for making the original version of this ballista. Go to check is post.

I would include also the no remix one print profile in order to give you the decision to decide which model download