Smallest bolt and nutThis i size you can print

[OdaNobunaga]

Hi guys, new member here. Just purchased a 5th gen makerbot desktop. If I want to print nuts and bolt, what is the smallest diameter I should use so I know how much I should scale it down. I want the bolt to be thick enough so it doesnt break easily. It is for a model that someone can use to demonstrate. The person needs to tighten and untighten the nuts and bolts.

[soofle616]

Define break easily? A solid 2mm diameter cylinder printed in ABS will be fairly sturdy as long as you don't make it too long but can still be broken by hand. Then of course you have to take into account the threads which aren't going to print well (if at all) on something that small. If you want a demonstration piece that will stand up to some abuse there are most likely some parts already available on thingiverse that you can download and print as is.