A screw sizing gauge for all standard imperial size screws (at least all the ones in the McMaster-Carr Catalog) as shown below.
The sides are angled and slotted to make it very easy to align and determine the length of screws/bolts with either a round head/flat bottom or with a flat head/chamfered bottom.
This model makes it easy to determine the length of your fasteners, thanks to the angled and slotted sides. Angled side helps hold screws in place for measurement, and the slots make it easy to determine the length of the screw either visually or by placing a fingernail between the slots as shown in the photos.
To measure screws with a flat bottom (including those with a hex, round, or socket head) use the left size of the gauge and place the flat bottom of the screw on top of the gauge and the shaft of the screw down through the channel.
To measure screws with a flat top and an angled bottom, use the right side of the gauge, placing the flat top of the screw against the flat portion of the gauge, with the head in the cutout.
The table below lists all of the supported thread sizes.
Thread Size | Diameter |
---|---|
#2 | 0.086" |
#3 | 0.099" |
#4 | 0.112" |
#5 | 0.125" |
#6 | 0.138" |
#7 | 0.151" |
#8 | 0.164 |
#9 | 0.177" |
3/16" | 0.1875" |
#10 | 0.190" |
#12 | 0.216" |
#14 | 0.242" |
1/4" | 0.25" |
#16 | 0.268" |
#18 | 0.294" |
5/16" | 0.3125" |
#20 | 0.320" |
#24 | 0.372" |
3/8" | 0.375" |
1/2" | 0.5" |
5/8" | 0.625" |
3/4" | 0.75" |
Note: Depending on your printer's calibration and the filament you use the holes may be very slightly undersized, if so it's helpful to screw a fastener of known size into the relevant hole and then use a drill/driver to spin the screw boring out the hole.
The author marked this model as their own original creation.