Sears Sewing Table Hinge Covers

The extension surfaces on the Sears sewing table in the Basement Sewing Room unfold from the top, leaving the hinges exposed:

Sears Sewing Table - hinge
Sears Sewing Table – hinge

Alas, quilts snag on the squared-off ends of the hinges, a situation that is not to be tolerated…

This protective cap isn’t as small as we’d like, but it must be that thick to cover the hinge, that long to cover the squared-off ends, and that wide for symmetry:

Sears Sewing Table Hinge Cover - solid model
Sears Sewing Table Hinge Cover – solid model

Two neodymium magnets fit in the holes and secure the cover to the all-steel “bronzed” hinges:

Sears Sewing Table - hinge covers
Sears Sewing Table – hinge covers

We’re not sure how well that will work in the long term, but early returns seem promising.

It could be slightly narrower left-to-right and maybe fewer vertices should be oriented differently.

The OpenSCAD source code as a GitHub gist:

// Vacuum Tube LED Lights
// Ed Nisley KE4ZNU January 2016
//- Extrusion parameters must match reality!
ThreadThick = 0.20;
ThreadWidth = 0.40;
HoleWindage = 0.2;
Protrusion = 0.1; // make holes end cleanly
inch = 25.4;
function IntegerMultiple(Size,Unit) = Unit * ceil(Size / Unit);
//----------------------
// Dimensions
Hinge = [7.0,52.0,6.0];
TopThick = 3*ThreadThick;
PlateThick = Hinge[2] + TopThick;
NumSides = 8*4;
//----------------------
// Useful routines
module PolyCyl(Dia,Height,ForceSides=0) { // based on nophead's polyholes
Sides = (ForceSides != 0) ? ForceSides : (ceil(Dia) + 2);
FixDia = Dia / cos(180/Sides);
cylinder(r=(FixDia + HoleWindage)/2,h=Height,$fn=Sides);
}
//----------------------
// Build it
difference() {
hull()
for (a=[0:7])
rotate(a*360/8)
translate([Hinge[1]/2,0,0])
scale([1.5,1.5,1])
sphere(r=PlateThick,$fn=NumSides);
hull()
for (k=[-1,1])
translate([0,Hinge[1]/2,k*(Hinge[2] - Hinge[0]/2)])
rotate([90,0,0]) rotate(180/8)
PolyCyl(Hinge[0],Hinge[1],8);
for (i=[-1,1])
translate([i*Hinge[1]/2,0,-Protrusion])
PolyCyl(4.8,2.5 + Protrusion,8);
translate([0,0,-PlateThick])
cube(2*[Hinge[1],Hinge[1],PlateThick],center=true);
}