You can download it via: https://www.thingiverse.com/thing:4300602

Background

Some manufactures put the VESA mount at the bottom of the screen, others in the middle. This can cause an issue for many situations, especially if monitors need to be used on a shared mount or in portrait mode.

Lets compare the pro’s cons of the mounting styles:

The result for a shared mount was quite noticeable.

The plate which pokes out, should connect to the monitor. The other to the VESA mount (See below).

Customisation

The mount can be customised in OpenSCAD, or via the Thingverse customiser: https://www.thingiverse.com/apps/customizer/run?thing_id=4300602.

The following parameters should be altered to suit your need.

Recently I have been building a train set, I will blog the progress, in six parts, highlighting how I get certain things done.

• Part 1 – Design and Woodwork
• Part 2 – Electrical design.
• Part 3 – Mechanical servicing
• Part 4 – Construction
• Part 5 – Painting of buildings and natural elements.
• Part 6 – Embedded computing and setup of DCC controllers.

Base Setup

Firstly I am designing a track that is movable from a storage hook on a garage, to a pool table in my living. This requires a baseboard, which I constructed with three cross breams, an MDF sheet and Tasmanian oak edging.

Designing the layout.

I used  the Simple Computer Aided Railway Modeller (SCARM) to plan my layout.  A read over an old German railway construction guide gave me a lot of practical hints as to what made a good layout.

Layout as viewed from the front.

layout as viewed from the rear.

Setting up the levels for hills and track.

The frame work is wood and MDF. Before getting into some neat tricks, lets look at a time lapse.

Steps:

• The track plan is printed 1:1 on a standard printer using 40 pieces of paper, there is a trick to doing this in SCARM.
• The layout is placed on the board and a toy train is run over it, just to get a feel for what it will be like to interact with.
• Spacers are cut on a table saw, so that the MDF can be set to the correct height for the track.
• Contours are cut from MDF using a jigsaw and the track carver up and placed on top of the MDF.
• Everything is assembled, a brad gun and wood glue is a quick way to get this done. I screw down the MDF, without glue, so I can  run wires later.

Train storage Cabinet.

I built a cabinet to hold the trains and keep them dust free.

• It is build like a picture frame, but I used the table saw to create a ‘grove cut’ on the frame.
• The grove allows two pieces of acrylic to slide like doors in the frame.
• If your not 100% on table saws, this video is terrific. (10:20 explains grove cuts).
• Using acrylic instead of glass lets me insert the doors after assembly (acrylic bends)
• The wood is Tasmanian oak (to match the table) and the finish is Linseed oil followed by a glossy furniture polish.
  • Frame Cutting  in Tasmanian oak is fraught with random peril. If you cut the long edges first, you can reuse failed cuts for the short edges, saving timber.

Introduction:

I needed some fan guards for my arcade machine and for a neat little entertainment centre hack.

Playing around I made a fish-eye honey-comb screen that looked pretty good. The pattern has larger holes near the centre of the fan and smaller holes where it counts.

How to make your own (with plans):

Making this is pretty easy if you have a laser cutter. If you don’t grab the .dxf  file and head of to your local laser/acrylic cutting business or makerspace.

The .dxf file is downloadable here.
A printable .png (good for the template) is downloadable here.

Q: I’m too lazy, can you sell me one?

Not any more (sorry).

I originally designed this as a two shelf unit, but trivially built it as a three shelf unit. The indents in the shelf place McCormick brand spices (Australian jar) at a pleasing interval, and seat them snugly. The rail is at the right height to keep the label viable and support the jar, without making removal difficult.

Machining was done on the artifactory‘s  CNC-router.

Final Result

Blue Prints

Image (click for larger)

Download

DXF (cad file)  here

Construction Notes

NB: I could not quite let go of my old school woodworking tendencies, so I made all tabs fit the slots exactly… This meant that after the router made its cut, the wood would expand a little and not fit in the slot. This is just what I wanted, preferring a bit of sanding at the end, so all would fit very snug. Nowadays I would wind back the slots 0.3 of a millimetre and let the glue do the rest.

The spices escutcheons I ended up 3d – printing and painting.  Nowadays there are plenty of 3d printing services should could offer a much better finish.

The stain I used was Wattyl Wood Gel – Honey Oak. I like how easy and fool proof these stains are. The results not bad either.

Photos of actual parts.

I spent a lot of time calculating track widths to make sure my circuit board could handle the current I was using.
Then I had to do more calculations for font ratios. so that that all lines were wide enough to work with the silk screening process.

Sick of this; I quickly used matlab to create a few charts so I could look up the answers quickly.
I thought I would share these charts and the matlab scripts, hope they are useful.

Font Ratio Chart

To my experience, In Eagle Cad (and others) font ratios for silk screens work best using vector fonts. The cam processor, other tools, and factory will often use vector fonts regardless; – so using vector fonts tends to keep things compatible. In the text properties dialogue you must set the ratio correctly so that (Size * Ratio) > “Factory Minimum Line Width”.  To make it worse, fonts are best wrangled using Mils (1/1000th of an inch [what’s an inch]).

Typically in Eagle Cad, I would set up text for silk-screening as follows.

Anyway, here is the chart

To use it:

• Find the colour that corresponds to your manufactures minimum silk screen resolution.
• Find your font height in the x-axis
• The corresponding ratio is given in the y-axis.

PCB Track Width Chart

Track width is related to a lot of factors (acceptable temperatures. how insulated the tracks are from the air, current, acceptable power loss, etc). For anything complicated (internal PCB layers, high currents/voltages, installation in a vehicle/ heater / oven) go do proper calculations!

Looking for a good track width calculator, I found this and like it a lot:  http://www.4pcb.com/trace-width-calculator.html

99% of the time, as a hobbyist, you just want an external PCB track that does not raise in temperature by more than 10ºC. You would be using either 0.5, 1 or 2 oz copper tracks (eek, more imperial units). So I implemented the formula presented on the calculator mentioned above in matlab.  Then I plotted 3 lines, one for each common copper thickness, creating charts that seem correct for normal hobbyist type situations.

Four charts follow metric and imperial versions of high and low current situations. Find the graph that suits you and keep it handy.

Disclaimer: Your mileage may vary. A) I may be wrong, and accept no liability for that. B) Silkscreens, lacquer, protective coatings, hot electrical components may invalidate these figures.  If your doing anything medical / military /  safety critical / mass produced / potentially dangerous; this page is not an appropriate source of information, go find an engineering book, or something peer reviewed.

Metric – High Amps

Metric – Low Amps

Mils (Imperial)- High Amps

Mils (Imperial)- Low Amps

Source Code

Fonts

%----------------------------------------------------------------------------------%
%                                    BUSYDUCKS.COM                                 %
%                            Making you pro-duck-tive                              %
%                                                                                  %
%  Author: Duckman   Date: 10/3/15   Ver: 1.0   Licence: Creative Commons (by-sa)  %
%                                                                                  %
%  Calculates silckscreen font ratios.                                             %
%  Compile with Matlab / Possibly Octave                                           %
%                                                                                  %
%  Permision given to freely copy/paste "code snippets" into your own code. For    %
%  other uses (e.g. derivative works) the Creative Commons Attribution Share-      %
%  alike license applies (cite busyducks.com). This means commercial use is ok.    %
%----------------------------------------------------------------------------------%
s = [10 : 5 : 100];
r = zeros(7, max(size(s)))

for x = 2:8
    r(x-1,:) = ((x*100) ./ s)';
    plot(s, r);
end

plot(s, r);
title('PCB Silk Screen Font Ratios')
xlabel('Font Height (Mils)')
ylabel('Font Ratio (%)')
legend('2 Mil', '3 Mil', '4 Mil', '5 Mil', '6 Mil', '7 Mil', '8 Mil');
grid on

Track Width

%----------------------------------------------------------------------------------%
%                                    BUSYDUCKS.COM                                 %
%                            Making you pro-duck-tive                              %
%                                                                                  %
%  Author: Duckman   Date: 10/3/15   Ver: 1.0   Licence: Creative Commons (by-sa)  %
%                                                                                  %
%  Calculates Track widths.                                                        %
%  Compile with Matlab / Possibly Octave                                           %
%                                                                                  %
%  Permision given to freely copy/paste "code snippets" into your own code. For    %
%  other uses (e.g. derivative works) the Creative Commons Attribution Share-      %
%  alike license applies (cite busyducks.com). This means commercial use is ok.    %
%----------------------------------------------------------------------------------%
function plotTraceWidth (metric, small)
%Formula from: http://www.4pcb.com/trace-width-calculator.html
%sample usage: plotTraceWidth(true, false);  
%will save a .png to the current working directory;  

amps = [0.1 : 0.1 : 10];
thickness = [0.5, 1, 2];

if(small)
    amps = amps * 0.2;
end

%external layers, IPC-2221
 k = 0.048;
 b = 0.44;
 c = 0.725;
 tempRise = 10; %deg C

factor = (k*tempRise^b);

for it = 1:3
    t = thickness(it);
    area = amps./factor;
    area = area.^(1/c);
    width(it,:) = (area./(t*1.378))';
end

if (metric)
    %convert to metric
    mmPerMil = 0.0254;
    width = width .* mmPerMil;
end

plot(amps, width);
title('PCB Track Width')
xlabel('Amps')
legend('0.5 oz', '1 oz', '2 oz', 2);

name = 'track_width';
if (metric)
    ylabel('Track Width (mm)')
    ticks = [1:15];
    name = [name '_metric'];
    if(small)
        ticks  = [0.2:0.2:2];
        name = [name '_small'];
    end
else
    ylabel('Track Width (Mils)')
    name = [name '_mils'];
    ticks = [50:50:2000];
    if(small)
         ticks = [10:10:200];
        name = [name '_small'];
    end
end
set(gca,'Ytick', ticks)
grid on
saveas(gcf, [name '.png']);