String Art Cardiac Line With Heart and LED's

In this Instructable I will show you how I make a Cardiac Line with Heart using String Art, I've been a fan of string art for quite some time but never got round to having a go at it, to give this project another dimension, I'm adding some WS1282B Addressable LED's and a simple repeating Comet sketch utilising Red LED'S the idea being that it will light up the spikes as it goes along then the LED's will go around the Heart as well and then to the end of the spikes.

Not much material needed for this project, I will be using an off cut of 10mm MDF some 20mm small headed nails, and some red crotchet cord.

I'm using my CNC machine to mark out where I need to hammer in the nails, and also cut out the inner of the Heart, I will be using the necessary safety equipment to include, Hearing protection, Eye Protection and dust mask.

Arduino Nano and Servo Shield

WS1282b LED strip

10mm depth MDF 420 x 200mm

Sandpaper

Blackboard Paint

Paint Brushes

Red Crochet cord/string

Small head nails, 20/25mm

Small Hammer

5V Power Supply

Soldering Iron

Solder

Hot Glue

To start this project, I've downloaded a free Cardiac line sketch and also a heart outline, Using Vetric desktop I've Imported the sketches in as Bitmaps and tweaked them to where I want them in the design.

Once I am happy with the layout, I place 1.5mm circles where I need to hammer in the nails, this could be done by eye of course.

I am cutting out the inner piece of the heart so I can place servos inside this area to mimic the beating heart in theory, there will also be a outline of the heart as well for guidance with the nails.

Again once I am happy with the layout, I create a pocket toolpath of 0.5mm for the circles on the cardiac line and finally I create a Profile toolpath to cut out the centre of the heart and tabs are designed into the sketch to hold it in place after cutting as we are cutting all the way through the MDF

The cutting files all use the same 1.5mm router bit so all cutting files can be saved as one, the file is renamed and sent to the desktop, then sent to the CNC machine down in the workshop.

I'm going to paint the MDF board before hammering the nails in, I should still be able to see the indents for the nails after applying.

I had an off cut of 10mm MDF Board @ 420 x 200mm and this was lightly sanded, I'm using Blackboard paint and this covers really well leaving no brush marks, it has a slight matt/satin finish and should work well with the red cotton.

To apply the paint I am using a cheap foam brush, making sure to get plenty of paint to the edges, MDF just soaks up the paint, It was a nice sunny day and I left outside to dry, which it did, very quickly.

Time to design the Layout and create some toolpaths:

With markers cut into the MDF I use some small headed panel Pins and hammer these into the MDF bearing in mind that the depth of the MDF is only 10mm, try and get these as straight as possible and using some long nose pliers makes it easier to hold the nails to tap them into the MDF, eyeing the nails from horizontal at eye level you can identify and adjust the nails as necessary.

I cut an outline of the heart as a guide with the CNC machine and spaced these nails out at 15mm, I ended up putting more nails in between these as well as I wanted the heart to be well populated with cord for the LED effect

With all Nails in position we can now look at applying the red crotchet cord:

Looking at various tutorials on Youtube etc, it was clear that there are many different ways of applying the string so I just started on the left hand side along the cardiac line, tying a knot on the starting nail and applying a little CA glue to secure, I started to wind the string around the nails, looking at my cardiac line sketch shows me the route I need to take, and wrap the cord around a nail using a loop knot every so often, I'm not using any set method here, it's pretty random but the effect begins to take shape, I work my way along to the heart and tie a knot to finish that line off, I did the same to the short length on the other side of the heart, tying knots and using CA Glue to secure.

With the Heart shape, I started off vertically to the opposing nails, and worked my way across the heart, then Diagonally, both ways, then horizontally, and finally Vertically again which filled the heart shape in nicely, for my first attempt at string art I was very pleased with the outcome.

Initially, I was going to use Servo's and see if I could make it look like the Heart was beating, but decided on using WS1282b LED's to highlight the string:

With LED's being a bit of an afterthought, I made up some MDF Strips and created an angle underneath the Cardiac Line, before gluing these in place I drilled some holes in 3 positions, these are for the LED cables.

I glued the MDF strips with CA glue and painted with the Blackboard paint, whilst this was drying I can prepare the LED strips, I had measured these prior to painting the board, and started by cutting some lengths of cable, I just used plain white cable, and stripped and tinned the ends with some solder.

I also tinned the Gnd, Data and 5v copper soldering pads on the LED strips.

WS1282b LED's are really good, You just cut in between the soldering pads when you cut to length and the LED's are individually addressable so are suitable for many applications.

With all LED's soldered I can now removing the backing and stick them in position, carefully bending the cables at right angles before pushing through the holes, Starting with the horizontal lengths first the moving onto the heart shape which was a bit trickier, the LED's didn't stick very well, so I used spots of CA glue around the Heart shape, and hot glue for the horizontal lengths.

With everything in place it was time for some connection soldering.

For this project I am using an Arduino Nano with a Servo shield, I use the Servo shields in many non servo based projects for 3 main reasons, they are really cheap, They have 2 sets of 5v and Ground pins and then just use the digital data pins as required, I think they are really good.

The shield will be secured with hot glue on the back of the board.

I soldered the joints between the LED's using heat shrink tubing to protect the joints, for the 5v, Gnd and Data connections to the shield, I soldered some female Dupont connectors, using heat shrink tubing as before, these were then pushed onto the corresponding pins on the shield, 5v Gnd and Pin 9 for the data.

I wanted this project to be both mains and battery powered, so I used a 9v Rechargeable battery and a Micro on/off switch, I had some 9v Battery Connectors, and with everything soldered the battery was held in place with some Velcro strips.

So with all connections made it's time to sort some code out.

The effect I wanted for this project was to mimic the Cardiac line, some like a Red chaser which would travel along the line then around the Heart shape, then onto the short horizontal strip, then repeat over.

FastLED Library is needed for the Sketch.

I found a sketch which I could manipulate to show just the Red LED's but it went from the start to the end and then came back in reverse, I really wanted a comet style effect with fading tale, in the end I just used the Rainbow effect comet, and omitted all the colours just leaving Red, the number of LED's in the comet was too many, so I dropped the number from 15 to 5 and the effect was too fast so I lengthened the delay, the effect now starts at the left hand side, it goes along the first horizontal line, around the Heart shape and then the shorter horizontal length, then repeats itself, Perfect! Just the effect that I wanted.

The LED's light up the cord nicely as well which is a bonus, the effect in a darkened rook is really cool.

Final Assumptions.

This was a project I've really enjoyed putting together, I had all components to hand which is always good and nice when it works out like that.

There were changes made as the project progressed which made things a little awkward like adding the LED's for Instance, but the effect takes all the nuances away, well worthwhile.

There you have it, my first attempt at String art with an added twist with the LED's

Hope you enjoyed this Instructable and thanks for looking.