Bolt/Screw identifying gauges, ISO M, ISO self-tapper, DIN wood

prusaprinters

<p>These are at least somewhat novel bolt-identifying gauges. &nbsp;The central bore is sized to the outer diameter of common bolts in the set (nominally, 0.1mm oversize, but your printer will vary). &nbsp;You should be able to put your bolt in, and where it stops is the size of screw it is, look at the markings just to the left. &nbsp;(Very short bolts, or ones with unusually large heads, might get caught by the head before they are caught by the shaft. &nbsp;You can eyeball it from there, or find a longer screw that seems to be the same size. &nbsp;Matching two bolts is easier then recognizing the size.) &nbsp;The exact feel of the thing will vary depending on your printer, but it should generally be noticeably loose on the next-largest size, and not go in to the next-smaller size without significant violence.</p><p><br>Once you've done that, there's two options on each of these. &nbsp;Put the screw along the ridged surfaces to either side to find the pitch of the screw. &nbsp;The matching pitch will clearly catch the screw, but it will just skate off the wrong sizes. &nbsp;You can read the pitch off at the back of the gauge, or look at the top for the name of that particular sub-series.</p><p>&nbsp;</p><h4>Included:</h4><p><br>ISO M-series bolts. &nbsp;These are far and away the most popular bolt series the world over for general use. &nbsp;Most M-series bolts are the "coarse" size, which is the assumed size if not specified. &nbsp;The major marking is the major diameter in mm, the back markings are the thread pitch in mm/turn. &nbsp;See https://en.wikipedia.org/wiki/ISO_metric_screw_thread<br>&nbsp;</p><p>The file named “DIN Wood” is from DIN 7998 “Threads and Thread Ends for Wood Screws”, which seem to be used on most wood screws sold in the UK &amp; EU, though I don't think I've ever seen anyone properly cite it. &nbsp;The front left gives the major diameter of the screw, including threads. &nbsp;Clockwise from there is the profile of the thread, the pitch in mm/turn (note that this is the nominal pitch, there's a fairly wide allowed range), and the pre-drill size (the size of the sold central shaft of the screw without the threads).</p><p>The file named “ISO Self-Tapping” is for ISO 1478 “Tapping screw thread”, which I believe to be for self-tapping sheet metal screws. &nbsp;The markings are the same as the DIN Wood set, with the exception of “gauge”, which is a dimensionless number (formerly) used to name the size.</p><p>&nbsp;</p><h4>Todo:</h4><p>&nbsp;</p><p>See Onshape document for ongoing development of more standards</p>