The Smell of Molten Projects in the Morning

Ed Nisley's Blog: Shop notes, electronics, firmware, machinery, 3D printing, laser cuttery, and curiosities. Contents: 100% human thinking, 0% AI slop.

The New Hotness

  • Proto Board Holder: 80×110 mm Version

    A simple holder for 80×110 mm prototyping boards:

    Random LED Dots - circuit board
    Random LED Dots – circuit board

    It’s similar to the holder for the LED current controller board, minus the center screws, plus nicely rounded corners and a cutout for wires emerging from underneath:

    Proto board holder
    Proto board holder

    Slic3r’s Hilbert Curve infill definitely looks better than the usual straight-line pattern:

    Circuit Board Holder - Slic3r preview
    Circuit Board Holder – Slic3r preview

    The OpenSCAD source code:

    // Test support frame for Hall Effect LED Blinky Light
    // Ed Nisley KE4ZNU - Sept 2013
    
    Layout = "Fancy";				// Fancy Plain
    
    PlainColor = "LightBlue";
    
    ClampFlange = true;
    
    //- Extrusion parameters - must match reality!
    
    ThreadThick = 0.25;
    ThreadWidth = 0.40;
    
    function IntegerMultiple(Size,Unit) = Unit * ceil(Size / Unit);
    
    Protrusion = 0.1;
    
    HoleWindage = 0.2;
    
    //- Screw sizes
    
    inch = 25.4;
    
    Tap4_40 = 0.089 * inch;
    Clear4_40 = 0.110 * inch;
    Head4_40 = 0.211 * inch;
    Head4_40Thick = 0.065 * inch;
    Nut4_40Dia = 0.228 * inch;
    Nut4_40Thick = 0.086 * inch;
    Washer4_40OD = 0.270 * inch;
    Washer4_40ID = 0.123 * inch;
    
    //- PCB sizes
    
    PCBSize = [110.0,80.0,1.5];
    PCBShelf = 2.0;
    
    Clearance = 2*[ThreadWidth,ThreadWidth,0];
    
    WallThick = IntegerMultiple(5.0,ThreadWidth);
    FrameHeight = 8.0;
    
    ScrewOffset = 0.0 + Clear4_40/2;
    
    OAHeight = FrameHeight + Clearance[2] + PCBSize[2];
    
    FlangeExtension = 5.0;
    FlangeThick = IntegerMultiple(2.0,ThreadThick);
    Flange = PCBSize
    			+ 2*[ScrewOffset,ScrewOffset,0]
    			+ 2*[Washer4_40OD,Washer4_40OD,0]
    			+ [2*FlangeExtension,2*FlangeExtension,(FlangeThick - PCBSize[2])]
    			;
    
    echo("Flange: ",Flange);
    NumSides = 4*5;
    
    WireChannel = [Flange[0],15.0,3.0 + PCBSize[2]];
    WireChannelOffset = [Flange[0]/2,25.0,( + FrameHeight + PCBSize[2] - WireChannel[2]/2)];
    
    //- Adjust hole diameter to make the size come out right
    
    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);
    }
    
    //- Put peg grid on build surface
    
    module ShowPegGrid(Space = 10.0,Size = 1.0) {
    
      RangeX = floor(100 / Space);
      RangeY = floor(125 / Space);
    
    	for (x=[-RangeX:RangeX])
    	  for (y=[-RangeY:RangeY])
    		translate([x*Space,y*Space,Size/2])
    		  %cube(Size,center=true);
    
    }
    
    //- Build it
    
    ShowPegGrid();
    
    difference() {
    	union() {									// body block and screw bosses
    		translate([0,0,OAHeight/2])
    			color(PlainColor)
    			cube(PCBSize + Clearance + [2*WallThick,2*WallThick,FrameHeight],center=true);
    		for (x=[-1,1], y=[-1,1]) {
    			translate([x*(PCBSize[0]/2 + ScrewOffset),
    						y*(PCBSize[1]/2 + ScrewOffset),
    						0])
    				color((Layout == "Fancy") ? "Orchid" : PlainColor)
    				cylinder(r=Washer4_40OD,h=OAHeight,$fn=NumSides);
    		}
    		if (ClampFlange)
    			color((Layout == "Fancy") ? "SeaGreen" : PlainColor)
    			linear_extrude(height=Flange[2])
    				hull()
    					for (i=[-1,1], j=[-1,1]) {
    						translate([i*(Flange[0]/2 - Washer4_40OD/2),j*(Flange[1]/2 - Washer4_40OD/2)])
    							circle(d=Washer4_40OD,$fn=NumSides);
    					}
    	}
    
    	for (x=[-1,1], y=[-1,1]) {				// screw holes and washer recesses
    		translate([x*(PCBSize[0]/2 + ScrewOffset),
    					y*(PCBSize[1]/2 + ScrewOffset),
    					-Protrusion])
    			rotate((x-1)*90)
    			PolyCyl(Tap4_40,(OAHeight + 2*Protrusion));
    		translate([x*(PCBSize[0]/2 + ScrewOffset),
    					y*(PCBSize[1]/2 + ScrewOffset),
    					OAHeight - PCBSize[2]])
    			PolyCyl(1.2*Washer4_40OD,(PCBSize[2] + Protrusion),NumSides);
    	}
    
    	translate([0,0,OAHeight/2])					// through hole below PCB
    		cube(PCBSize - 2*[PCBShelf,PCBShelf,0] + [0,0,2*OAHeight],center=true);
    
    	translate([0,0,(OAHeight - (PCBSize[2] + Clearance[2])/2 + Protrusion/2)])	// PCB pocket on top
    		cube(PCBSize + Clearance + [0,0,Protrusion],center=true);
    
    	translate(WireChannelOffset)									// clearance for cable on solder side
    		cube(WireChannel + [0,0,Protrusion],center=true);
    }