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Ethical Cloning – Shaun and Dolly the Sheep

3D Printing

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Many believe that cloning of any life-form is immoral, cruel and unethical. The process interferes the rules of nature which can bring biological imbalances to our ecosystem. However, living in the world of Shaun the Sheep and a bunch of his innocent friends, today, they welcomed a new family member as it slowly materialised from a mysterious dance floor, a.k.a. the Reprap.

Having built a 3D printer a few months ago and undergone intensive fine tuning, my Reprap is now able to rapidly print objects in high accuracy. As there was a handful of Shaun the Sheep sitting around on my desk which were at a size that feasible in cloning, I took the liberty of  cloning the sheep leader – Shaun to make Dolly the Sheep.

As some would expect using 3D scanner to quickly convert a physical object into a computer model, I didn’t have such device. Therefore, doing it the traditional way by taking photos of Shaun in varies angles, then importing them into my favorite 3D software, 3ds Max, I was able to model it in slightly

less than an hour.

Since this was a toy figure and accuracy wasn’t the top priority, as long as the portions and shape were in portion to the photos, I was then able to quickly add a noise modifier to create the bumped texture for the sheep’s wool.

The Main challenge for printing this figure was the overhanging parts like the tail, ears and the body. The first try for printing was separating its legs and body into 2 parts. The legs could be printed as a self standing model, then I manually added supporting support for the ears and tail.

In the first attempt, I realised that the supporting structure was made too big. Even though it was possible to remove the supports but it left so many rough ends that was impractical to clean. Therefore my second attempt was only to add supports to the ears and tail in the form or round cylinders which only touched the overhanging points of the slice.

The common problem with printing small parts in PLA (polylatic acid) was having a short layer time. Once a layer is printed, and before it became cool and solidify, applying additional layers on top would end up smearing and melting plastics by the hotend because it is still very soft. As a result, I either had to reduce the layer time or print 2 or more copies together.

With the improved model, I was then able to create a much better print as well as using a lot less material for the supporting structure. All I had to do afterwards was to glue the 2 parts together then by using an extra fine sand paper to remove the tool path pattern and the layer lines.

Finally… Dolly is now standing up and Shaun’s family has welcomed his arrival!

All images here

  

One Response to this post
  1. Posted on 11/09/2012 by googlepo

    Great article . Will definitely copy it to my website.

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