The New Hotness

The Slic3r preview shows a bit more detail:

Hydrant Wrench - Slic3r preview — Hydrant Wrench – Slic3r preview

Even an inch-thick handle wouldn’t have enough mojo for the task.

Wikipedia has the equations you need to go from the easily measured “height” (vertex to opposite side) dimension to the pentagon’s “outside radius”, which equals the radius of the circumscribed circle needed by OpenSCAD.

The OpenSCAD source code as a GitHub Gist:

	// Hydrant Wrench
	// Ed Nisley KE4ZNU – September 2017

	/* [Extrusion] */

	ThreadThick = 0.25; // [0.20, 0.25]
	ThreadWidth = 0.40; // [0.40]

	function IntegerMultiple(Size,Unit) = Unit * ceil(Size / Unit);

	Protrusion = 0.01; // [0.01, 0.1]

	HoleWindage = 0.2;

	//- Sizes
	/* [Dimensions] */

	NumFlats = 5; // this is not a variable for this geometry!

	Height = 39.0; // pentagon flat-to-vertex measurement
	Side = Height / 1.539;
	echo(str("Side:",Side));

	Radius = Side / 1.176;
	echo(str("Radius: ",Radius));

	WrenchDia = 2*Radius; // pentagon circumcircle diameter
	echo(str("Wrench dia:",WrenchDia));

	JawWidth = 10.0;

	JawOD = 2*JawWidth + WrenchDia;
	echo(str("Jaw OD: ",JawOD));

	WrenchThick = 5.0;

	HandleLength = 2*JawOD;
	HandleWidth = 25.0;

	//- Build things

	difference() {
	linear_extrude(height=WrenchThick,convexity=4) {
	hull() { // taper wrench body to handle
	circle(d=JawOD);
	translate([0.75*JawOD,0,0])
	circle(d=HandleWidth);
	}
	hull() { // handle
	translate([0.75*JawOD,0,0])
	circle(d=HandleWidth);
	translate([HandleLength,0,0])
	circle(d=HandleWidth);
	}
	}
	translate([0,0,-Protrusion])
	rotate(180/NumFlats)
	cylinder(d=WrenchDia,h=(WrenchThick + 2*Protrusion),$fn=NumFlats);

	translate([WrenchDia,0,WrenchThick – 3*ThreadThick])
	linear_extrude(3*ThreadThick + Protrusion,convexity=10)
	text(text=str("Fire Hydrant!"),size=8,spacing=1.20,font="Arial",halign="left",valign="center");
	}

view raw Hydrant Wrench.scad hosted with ❤ by GitHub

Sorry ’bout that … had to do it.