3D Printing + Sugru = Precision Rubber Parts! (iPhone 4/4S and 5) + Video

Print your own desktop manufacturing kit to produce precision rubber parts directly onto the iPhone 4/4S or iPhone 5 with sugru !

We developed this project so that makers, engineers and designers could test the process and understand how to desktop manufacture precision rubber parts with sugru.

The mold and process is not perfect but was developed to demonstrate the potential for using sugru in desktop manufacturing and would love to hear your suggestions.

All the files are open source and free to download from Thingiverse.

You can also order your mold directly from Shapeways.

Get your maker mits on sugru here :)

Kudos to carsonlau from the sugru community who created this project last year and inspired to make this.

http://sugru.com/blog/how-to-mold-precise-rubber-parts-with-sugru/

STUFF YOU NEED:

3D printed mold.
sugru (this project uses just one 5g mini pack)
Washing up liquid
Small paint brush
8 x 10/32 x 1" Hex head bolts (m5 x 25mm) + washers and wing nuts
Toothbrush (we trimmed the bristles from an old toothbrush as it worked better to clean the mold)
Toliet paper
Scalpel
Menda plastic spludger tool (our favourite tool for working with sugru) (or piece of plastic)

You might also need:
Sandpaper
Finger files

Step 1: Prepare Your Mold

In this guide we demonstrate the process with an iPhone 4/4S. (Molds are also available for the iPhone 5)

To get your hands on a mold, you can find it open source and free to download from Thingiverse ready to print on your 3D printer.

You can also order your mold directly from Shapeways.

In this guide, we used an SLS print from Shapeways which has a higher resolution but is more expensive to print.

To begin with, check that the mold fits together perfectly.
Examine the accuracy of the shut lines and sand or file parts if necessary to make sure they meet properly.

Step 2: Apply Release Agent (washing Up Liquid)

Apply neat washing up liquid to the sides of the mold that will be in direct contact with sugru and also on the sides which it will spill out onto (flash).
Apply just a thin layer and make sure there is no build up of washing up liquid as this may run on to the phone and stop the sugru from adhering.

Step 3: Clean Your IPhone and Assemble Mold.

Clean the iPhone with paper towel making sure it is free from grease and dirt.

Pop the iPhone into the mold.

Assemble the mold, insert the bolts, washers and tighten the wing nuts.
Tighten so that the mould does not move but do not over tighten as this could break it.

Step 4: Charge the Mold - Apply Sugru.

Cut open you sugru and break into 4 equal pieces (one piece per corner)

Break a piece in half and press it into a small flat sausage.

Insert the flat sausages into the gap between the mold and the iPhone on the front and back of the mold and fold over the corner of the phone. By working gradually with smaller pieces we can ensure a strong bond to the phone.

Step 5: Pre Form the Sugru.

Press and shape the sugru into a pyramid. Repeat the last two steps for each corner of the phone.

Step 6: Apply Washing Up Liquid to the Former

Apply a thin layer of washing up liquid to the third piece of the mold. You are now ready for the forming process.

Step 7: Step 1 of the Forming Process.

The forming process is a three step process, this ensures that you never apply too much force onto the sugru (this forces the washing up liquid out of the mold and causes problems)

Start by gently pressing the 3rd piece (former) of the mould onto the sugru.
In the image there is a clear gap between the mold parts. At this distance, stop and remove the 3rd piece again.

Step 8: Trim Flash + Step 2 of the Forming Process

Trim away the flash using a scalpel or plastic spludger.

Apply a fresh layer of washing up liquid to the 3rd piece of the mold and press onto the sugru again.
This time pressing it a little further and again removing the flash.

Step 9: Step 3 of the Forming Process

On the third and final time, press the mold parts firmly together.

Step 10: Repeat Process on All 4 Corners.

Remove the 3rd piece and trim the remaining flash with a scalpel.

Repeat for each corner.

Step 11: De-mold

Once all 4 corners are molded, it's time to remove the iPhone from the mold.

Undo the wing nuts and carefully lift off the the top of the mold. Gently lift it as straight as possible.