thoughts on hardware (nuts and bolts)

I'm working on a new machine and wanted some second opinions.
What do you guys think is 'too many' in terms of number of unique nuts and bolt used to assemble a 3d printer, from the average joe's perspective when building a kit. Too few and you end up using parts that arent ideal for a particular assembly, too many and it becomes a mess to manage. Any ideas for a magic number? Currently my design uses three types of bolts, and their corresponding nuts/washers/bearings(where nessecary). It seems reasonable to me but second opinions are always nice. Part of my goal for the printrr is to make it user friendly in terms of assembly/maintainability.

Sorry about the double post, can a mod delete this? I tried posting earlier but it kept blocking it as spam and i didnt think it went through.

Naturally fewer is better. I will design a part to use an existing screw whenever possible, unfortunately sometimes you just have no choice. When you say three types do you mean three total part numbers or multiple lengths of three different diameters? Three total part numbers is really good.

For what its worth my current project has 9 seperate fastener part numbers plus M3/M4 nuts. I was not happy to use such a large number of fasteners but the design uses a lot of COTS parts which force specific fasteners.

In general I find that washers (especially lock washers) are overused, but they are cheap so it might not matter.

Edited 1 time(s). Last edit at 06/20/2017 12:20PM by 691175002.

It will use three unique bolts. One length M8, one length M4, one length M3. Obviously there will be more than three bolts but there will only be 3 unique bolts, so three part numbers. Each one will require its respective bolt and washer. I find washers nessecary as its easy to drive the bolt head into or through the shell of a 3d printed part without them