Found some printable M8 screws on Thingiverse (https://www.thingiverse.com/thing:4805480), which made me wonder if I can get M4 screws, just by resizing them factor 0.5.

  • 2
    $\begingroup$ Nope, and in addition / FYI, there are multiple fine thread versions that are used fairly often (e.g. in automobiles), so it's not enough to refer to an "M8", but must specify M8x1.25 or M8x1 or M8x.75 $\endgroup$
    – Pete W
    Commented Apr 13, 2021 at 22:15
  • $\begingroup$ @PeteW If I had to guess though, I would always guess the coarse thread. $\endgroup$
    – DKNguyen
    Commented Apr 14, 2021 at 2:55
  • $\begingroup$ @PeteW - In my experience with both; the convention in ASME drawings is to always state the pitch with the size, ISO based drawing convention is to state the pitch only when it is not coarse. Saves trying to remember all of the coarse pitch sizes at least! $\endgroup$
    – Will.W
    Commented Apr 18, 2021 at 9:19

1 Answer 1


The ISO metric bolt has its diameter as the numeral part of the name.

So M8 has a diameter of 8mm compared to that of the M4 bolt. So far scaling would make sense.

However, the pitch of them is not proportional and would be wrong if you scale them.

her is a figure from Wikipedia. Wiki


enter image description here


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.