Much like your car, the number of miles, or the number of prints that you can get out of it is entirely up to how well you can maintain it.
A 3D Printer is a machine, and a machine needs general maintenance; if you see something starting to break - or get worn out - or anything abnormal, fix it.
I am sure that if you had something like a MakerBot, it would require less maintenance then a fully home built machine, but if you are building it from scratch, I am sure you don't mind.
I am still rocking a 3 year old home built MendalMax, and have both made some improvements, and had to make some repairs along the way - but it is still in damn good condition.
For a $600 investment, I can say you will get a few years out of it if you take proper care of it. By the time the end of its life comes (5+ years), I am sure there will be much better printers available for cheaper, and you will never look back :)
- Tighten all your nuts and bolts
- Keep it calibrated
- Keep belts properly tensioned
- Oil X, Y, and Z rods
- Clean of any dust and scrap plastic (compressed air can?)
- Clean hobbed bolt
- Clean extruder
- Ensure all electronic connections are secure
- Check wires at points of movement for wear
!remindme 5years