PCB Artwork - Coaster (Dark Chocolate Imprint)

Introduction 
In this blog, the circuit board tool Altium Designer was used to create a circuit board (PCB) coaster with an imprint on the PCB resembling a dark chocolate (cocoa) molecule.

Prototype (Coffee) Cup Coasters

Finding a Suitable Source
Before the PCB design process could be started, a suitable molecule for the PCB imprint was found online. A representation of a molecule that was more uniformly shaped was chosen to suit the shape of the PCB. Such a specific layout may not be available without manipulating the molecule’s layout.

Dark Chocolate Molecule
(Courtesy biobeat.nigms.nih.gov)

The molecule in this post could have been caffeine, tea or several water molecules however for this post dark chocolate was chosen.

Creating the PCB
To begin creating the PCB artwork for the coaster in Altium, a circular arc on mechanical layer 1, with a 90 mm diameter was drawn. The 80 mm PCB diameter used in the previous coffee cup coaster was marginally too small however the overall PCB dimension should be adjusted on a project-by-project basis.

Coaster PCB Shape and Size

Next, the names of the individual chemicals were added as top copper layer strings. The font type sans serif was selected over serif for a modern appearance. Then the bonds between the chemical text were added to the PCB on the top overlay. Various placement and shuffling of top overlay line lengths and text were needed.

Coaster Top and Silk Layers

The next step was to duplicate the top copper layer strings. The layer properties of the copied strings were changed to the mechanical top solder layer and then placed over the top layer strings. This effectively removed the top solder mask exposing the PCB copper. Having a separate top solder layer allows for manipulation of the size and placement.

Coaster Top Solder and Silk Layers

Viewing the PCB using the Altium 3D feature yields the image below for the black solder mask.

Coaster in 3D

PCB Export
The requirements of the desired PCB manufacturer were checked to prepare the PCB artwork for manufacturing. As the files for the PCB manufacturer are usually in the Gerber format, the export settings for the Gerbers should be verified with the manufacturer.

Manufacturing
As noted in other blogs, the appearance and cost of the manufactured PCB may vary based on Production settings. For the PCB in this post, a black solder mask is more expensive than a green solder mask, the latter being more common.

In this post, the PCB thickness was kept at 1.6 mm since this is usually the most cost-effective thickness, a lead-free HASL (Hot Air Solder Levelled) surface finish was chosen over a lead finish and the solder mask was produced in two separate colours, green and black, to exhibit the visual difference. Lastly, the PCB manufacturer's marking was specified on the PCB bottom side overlay.

Downloads
The Gerber file can be downloaded from the link below. The files should be checked before use.

For the Gerbers the Altium export settings here were followed.

Coaster Gerber Files

PCB Artwork - Model Rocket

Introduction 
In this blog the circuit board tool, Altium Designer, was used to create circuit board artwork in the form of a model rocket keyring. The recent prototype of the Wi-Fi rocket launcher post inspired this blog.

Model Rocket Keyring

PCB Artwork
To start the project, a black-and-white image of the rocket keyring was downloaded from a suitable website. An image called SpaceShipOne was downloaded from CleanPNG (all credits).

Scaled Rocket Image (Courtesy CleanPNG)

The original image was scaled by 25% before importing into Altium. Shown below is the result of the import. As can be seen by the imported image, the image did not produce solid lines which was required for the keyring.

Imported Rocket Image

Rather than manipulating the PNG file for an improved import result within Altium, the outline of the imported PNG was drawn over with circuit board tracks (traces). For simple shapes such as the rocket, using Altium is relatively easy however many other packages could be used to achieve the same drawing.

Drafting Rocket Primitives

The image below shows the imported image and the hand-drawn image side by side. Minor changes can be noticed on the rocket fins compared to the original image.

Comparison of Hand Drawn and Imported Rocket Designs

One item not included in the circuit board file was the board outline. This is commonly added on a mechanical layer but this was not added to the design. It has been noted that many other free software tools are being used to create circuit board artwork. Therefore, with the alternative software in mind, the board manufacturer was asked to add a circuit board outline.

Manufacturing
For the circuit board manufacturing, the company JLCPCB was used. JLC included a board outline 0.1 mm from the circuit board trace. The final product is shown below.

Model Rocket Keyring

Download
For anyone interested in producing a keyring, the Gerber file pack is available below. A board outline should be spaced at least 0.1 mm from the outermost circuit board traces.

Rocket Keyring Gerbers

PCB Artwork - Coffee Cup Coaster

Introduction 

In a previous blog, the circuit board drafting tool Altium Designer was used to create circuit board (PCB) artwork. In this blog, a coffee cup coaster was created using the same technique.

Coffee Cup Holder Front and Back

Removing Colour and Changing the File Format

To begin, select the desired clipart image from your preferred site, such as the image used in this post - a coffee cup. All credit to the original designer and provider of the coffee cup.

Coffee Cup Clipart (Credit Clip Library)

Import the image into an editing tool such as GIMP, Photoshop, or a free online editor. Remove any colour from the image (black and white) to prepare it for use on the PCB. Increase the thickness of the image as needed to ensure ease of production.
After the image editing is complete, save the updated image in a PNG format. This format allows for easy copying and pasting into Altium Designer.

Creating the PCB

To begin creating the PCB artwork for our coffee cup coaster, a circular arc (mechanical layer 1) with an 80 mm diameter to the PCB. This arc defined the board shape and should be larger than the image. An 80 mm diameter suits cups, a 100 mm to 120 mm diameter would suits most mugs.

Coaster PCB Shape and Size

Next, the PNG file contents were copied and pasted into Altium Designer. The imported image is represented by various regions which can be moved as needed.

For the coffee cup, the top copper layer was adjusted using the Properties dialogue box.

Manual Solder Mask Expansion Setting in Altium

To ensure a minimum distance between the solder mask and the copper layer, the solder mask expansion of the copper region was manually reduced to zero using the Properties dialog.

The steam seen above the coffee image was changed to a top-layer silk screen using the same Properties dialog in Altium.

Coffee Cup Coaster in Altium 2D

PCB Export

To prepare the PCB artwork for manufacturing, the file format (Gerber) needs to meet the requirements of the selected PCB supplier. The format may vary depending on the manufacturer and is usually listed on their website. In this post, the JLCPCB supplier was utilised to manufacture the PCB.

Manufacturing

The final appearance and cost of the coaster can vary greatly based on various factors. These factors include the thickness of the circuit board material, surface finish, solder mask and silkscreen colour.
In this post, the board thickness was maintained at 1.6 mm, the surface finish was lead-free HASL (Hot Air Solder Levelled), the solder mask was changed to black on the top side only and the silk screen was kept as white.

Coffee Cup Coaster in Altium 3D

Final Product

Pictured below is an image of the board as supplied by the manufacturer.

Coffee Cup Coaster on the Bench

Due to lighting the contract between the silver surface and the white silkscreen is not captured. To increase the longevity of the coaster, a clear epoxy or a hard-wearing lacquer could be applied. This will prevent the HASL coating from becoming tarnished over time.

Coaster in Use

Altium PCB Art

Summary
This blog outlines techniques to produce PCB visual art utilising a Printed Circuit Board (PCB) design package with image editing software. Below is an example of a PCB, with exposed copper, portraying a Monkeyface.

Monkeyface as PCB Artwork

Preamble
During the pandemic lockdown, there was an opportunity to use a PCB design package, Altium Designer (Altium), for basic visual 'PCB' art. While Altium can be used independently to create visual art, utilising a free image editing package such as GIMP, Inkscape or a commercial package such as Photoshop or Corel will assist with altering images.

The image editing methods described in this blog are experimental; alternative techniques are welcomed!

Software Alternatives
Free PCB software design packages which include KiCad, Design Spark and PCBWeb are capable of creating similar PCB art.

Source Material
Source material, such as an image or a DXF file, are usually required with a PCB design package. Monochrome images can ordinarily be pasted directly into Altium however loss in greyscale images can occur with lighter tones. Colour images require conversion to black and white. Images can be converted into a DXF format and imported into Altium.

Example 1: Colour to Monochrome - Cloud Sun
All credit to the creator of the artwork, Sushant Wadte, for the example image below.

Colour images are changed into monochrome using various methods. The subsequent method, using filters in Inkscape, produces reasonable results in images with large objects.

Cartoon Sun Cloud - Courtesy PNGItem. Creator - Sushant Wadte

Using the 'Greyscale' filter in Inkscape, the colour image was converted to monochrome. The colour channels and lightness were adjusted to improve the monochrome image.

Inkscape Greyscale Filter - Cartoon Sun Cloud

For importing into Altium, the monochrome image background was changed to white and all other features were converted to black.

Inkscape Black and White Cartoon Sun Cloud

Filling the cloud and sun rays with black was performed using Inkscape's fill bounded areas tool. The image background was filled with white.

The converted image was saved as a BMP and PNG file.

Altium Script (Alternative Import Method)
The Altium script PCBLogoCreator was used to convert the bitmap image into a representation in tracks.

Altium Dialog Box Running PCBLogoCreator Script

Running the Altium script on the black and white image for a PCB, yielded the resulting image shown below.

Altium Script Converted Cartoon Sun Cloud 

The image converted by the script was useable, although there are two points to highlight. Firstly, converting the image results in hundreds of tracks which can load up the CPU when moving the tracks. Secondly, the tracks cannot be selected and converted to a polygon or region.

Altium Script Conversion Lines Cartoon Sun Cloud

Placing Sun Cloud PNG Into Altium

The saved PNG image can make its way into Altium using two methods. One method is to cut and paste into an Altium PCB. Another method is to use the menu command, Place Object.

The same black and white image in the previous section was pasted into Altium onto the top layer (copper).

Altium Pasted PNG Cartoon Sun Cloud

Selecting the cloud on the pasted image shows that the process of pasting into Altium converts the image dark areas to regions.

Object Tweaks

The image was initially pasted on the PCB top layer (copper) although it is possible to paste onto other layers such as the top overlay (silkscreen).

Altium 3D Top Silk Unmodified Cartoon Sun Cloud

The cloud was changed to top layer silk and the sun and rays left as copper. To change the cloud from top copper to top silk, the cloud region was modified.

Altium Cloud Region Selection

The Properties (legacy PCB Inspector) was opened to change the region from top copper to top silk. 

Altium Region Layer Change

With the cloud changed to silk, the remaining objects required removal of the solder mask (green coating).

Altium Top Silk Cloud Region 

To alter the solder mask of the remaining objects, each region was selected. The region 'Properties' (legacy PCB Inspector) was opened and the 'Solder Mask' rule changed.

Altium Object Solder Mask Expansion

The 'Solder Mask Expansion' setting was set to 'Manual'. Having a 'Solder Mask Expansion' value may be required depending on the capabilities of the PCB manufacturing house.

The resulting capture of the PCB, in 3D, shows the changes.

Altium 3D Modified Cartoon Sun Cloud

PCB Shape - Cloud Sun

The PCB outline was defined using tracks on Mechanical 1 layer as this layer is commonly used to define the shape of the PCB.

PCB Finish - Cloud Sun

For the example PCB displayed above, a green solder mask and ENIG copper finish (gold) were used. Some alternative solder mask colours are red, blue, yellow, white, black and purple. The copper can be left raw to discolour due to oxidisation or coated with a finish such as lead-free solder, tin, silver or gold.

Example 2: Colour to Monochrome - Monkey

Converting the monkey image for use as art in Altium used a similar method to the first example.

Monkey Face - Courtesy Free.ClipArtof.com

Some additional work was required to remove the colour and gradients. Firstly, the Greyscale filter in Inkscape was used to convert the image to monochrome.

Inkscape Greyscale Filter - Cartoon Monkey Face

Using the 'Fill Bounded Areas' tool in Inkscape, the areas with colour gradients were filled with white. There was a gradient (shadow) below the face which was also filled with white. 

Inkscape Monkey Face Monochrome No Shading

Visible lines in the image may be imported by Altium and therefore these lines were removed. Using Inkscape's 'Brilliance' filter, the Brightness and Lightness settings were adjusted to remove the lines. Producing the desired results with this tool can take some tweaking.

Inkscape Brilliance Filter - Cartoon Monkey Face

Monkey Black and White

The cut and paste results in Altium are significantly improved when all colours are black. The 'Fill Bounded Areas' tool was used to ensure all regions were converted to black.

Inkscape Cartoon Monkey Face All Black Lines

The image in Inkscape was exported as a PNG ready for import into Altium.

Placing Cartoon Monkey PNG Into Altium

Using the Place Object command in Altium, the Cartoon Monkey was added to a new blank PCB on the top copper layer.

Altium Cartoon Monkey Face Import

Object Tweaks

For the Monkey design, all copper areas were changed to show exposed copper. The Solder Mask expansion changed to manual for all the copper areas.

Altium Cartoon Monkey Face Copper Selected

Viewing in 3D showed that the solder mask was removed from the copper.

Altium Cartoon Monkey Face Exposed Copper

PCB Shape - Monkey

The PCB outline was defined using arcs around the Monkey head. These arcs were drawn on the Mechanical 1 layer as shown in the image below.

Altium Cartoon Monkey Face Mech1 Layer

Setting the PCB shape was performed with the Mechanical 1 Layer arcs selected then using the Altium command Define PCB from Selected Objects.

Altium Cartoon Monkey Face Board Cutout

Final Touches - Monkey

Holes were made for the Monkey eyes using two pads having a 3.8 mm holes.

Altium Cartoon Monkey Face Eye Holes

Pictured below is the final PCB in 3D with exposed copper and holes for the eyes.

Altium Cartoon Monkey Face Final

PCB Finish - Monkey

A black solder mask and ENIG copper finish (gold) were used for the PCB finish.

Example 2: Alternative Monkey

To achieve a PCB design similar to the image shown at the beginning of the blog, the black and white image required inversion. At the previous step 'Monkey Black and White', the image was inverted.

Monkey Head as PCB Artwork

The Inversion Filter in Inkscape performed the conversion.

Inkscape Invert Cartoon Monkey Face

Adding a Border

After the Inversion, the image boundaries became the four extremities of the Monkeyface. Adding a black background using Inkscape assisted when importing the image into Altium.

Inkscape Monkey Face Inverted with Border

With a black rectangle drawn in Inkscape, the inside area was filled with black. 

Inkscape Monkey Face Inverted with Background

Placing Cartoon Monkey PNG Into Altium

Below is the PCB capture after using the Place Object command in Altium.

Altium Cartoon Monkey Face Alternate Import

Object Tweaks

For the alternate Monkey design, the internal copper areas were changed to exposed copper.

Altium Cartoon Monkey Face Alternate Exposed Copper

PCB Shape - Monkey

The PCB outline comprised of two parts, a board cutout and the PCB shape on the Mechanical 1 layer. Firstly, the remaining copper region outside the Monkeyface was selected then changed into a 'Board Cutout'.

Altium Copper Region to Board Cutout

Viewing in 2D shows the board cutout.

Altium Cartoon Monkey Face 2D Cutout

Secondly, a Mechanical 1 Layer was added onto the PCB to define the physical PCB size. The Mechanical 1 Layer tracks were selected and the PCB shape was defined from the selected objects.

Altium Cartoon Monkey Face Alternate Mech 1 Layer

Viewing the PCB in Altium 3D.

Altium Cartoon Monkey Face Alternate Final

Alternative PCB Shapes

Inkscape provides a tool called Trace Outline which can be useful when the shape of the PCB must be marginally different to the image shape. A modified outline can be imported into Altium as a separate object which would then be used to define the outline of the PCB.

Inkscape Monkey Face Trace Outline

Final Thoughts

The methods described in this blog can be used independently or partnered with electronic circuits to create visual PCB art. 

It should be noted that the placement of copper as art is not limited to either side of the PCB but internal copper layers also. Using only internal copper and a thinner PCB (1 mm or less) produces near translucent effects with the suitable backlighting.

Downloads

Altium PCB and associated Gerber files.

Altium Sun Cloud PCB

Cloud Sun Gerber

Altium Monkey Original PCB

Monkey Original Gerber

Altium Monkey Alternative PCB

Monkey Alternative Gerber