For a while now, I have been thinking about designing things such as small bedside tables, game/dvd/bluray racks for 3d printing. I've always thought that making them modular would be a good way to go about doing this as well.
Modular design would help to create an end result that is vastly larger than the print volume of my 3d printer. I might even be able to recycle models for use in other projects. However, I'm not sure of what I need to think about if I decide to go ahead with these ideas I have floating around in my head.
I'm assuming that certain joints (dovetail, etc), tolerances for different types of plastic due to shrinkage, and print settings (% infill, in particular) would be important to have thought about and evaluated to some extent, but I'm not sure about what else I might be missing.
So my question is to anyone who has designed anything to be modularly printed. Have you really had to think carefully about the engineering side of the print? Or am I simply overthinking this? Should I just design what I want and give it reasonable infill, walls and whatnot, and just go for a trial and error approach? I'm sure there is a method to this madness, but is a concrete understanding of this type of engineering absolutely paramount when it comes to this sort of stuff?
EDIT: Although I've marked darth pixel's answer as accepted, I'm still going to follow JKEngineer's advise and check out that book as well since I feel as though proper engineering techniques alongside a good mentality towards how I would tackle the problem (as outlined in darth pixel's answer) would prove to yield better results in the long run.
All printers are designed with an idea of WYSIWYG for sure. Depending on:
- printer - type/quality/settings/configuration/assembly precission
- filament - type/quality/shrinkage
- user skills - manual/using app proficiency
- model complexity
- environment conditions and so on
you can get different results.
I venture to say users know their printers (after some time and by trials and errors) so they know how to manage dimensions to compensate all above so you will get this knowledge too.
Mathematical formula can describe shrinkage of the material, all other elements are very hard to describe (mathematically) in a general way.
Of course someone can simplify it and say: more money you spend better effects you'll get. It's sometimes true ;)
So all your modular things will be better and better if you will increase (what is to be increased) in above points especially "user skills".
Is engineering paramount? It depends of whay you gonna create. If your modular things have to lock itself, have to have threads, screws and such stuff then this is engineering. Is it the most important part of the design? Not necessarily.
This is my receipt:
think > imagine > design > rethink > redesign > give it a try > get back to thinking