Question About Screw Hole Counts and Locations for Each Screw Size for Romi Chassis

According to the Romi Chassis User’s Guide, the chassis can accept #2-56, #4-40, M2 and M3 screws. I’ve printed the chassis diagram to study the pattern of holes and try to figure out which holes can accept which screw sizes. My question is: has anyone counted the number of holes on the chassis that will accept a #2-56 screw and identified which holes they are on the chassis? And done the same for the remaining screw sizes, e.g. how many holes will take a #4-40 size, and where are they on the chassis? And for M2 and M3?

This is really just an academic question. I’m not asking anyone to do an actual count and mapping in this manner. I’m not even sure how this knowledge can be useful – because you see I do not have experience with building robots or even much experience with constructing other structures from plastic, standoffs, and screws. So there is no real need to answer this question.

Thanks so much



#2-56 and M2 screws are very close to the same size and can both fit in the smaller sized holes on the Romi chassis. Similarly, #4-40 and M3 screws can both fit in the larger sized mounting holes on the chassis. The difference in the two hole sizes should be big enough to visually tell which ones are intended for each screw sizes. There are also a few holes on the chassis specifically intended for M2.5 screws for mounting a Raspberry Pi or a board with the common Arduino form factor. You can find more information about mounting holes in the “Dimensions and mounting holes” section in the Romi user’s guide.