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





Introduction: 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. 



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
Menda plastic spludger tool (our favourite tool for working with sugru) (or piece of plastic)

You might also need:
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.

Step 12: Remove the IPhone

Carefully remove the iPhone. Again try to remove is as straight as possible.

Step 13: Leave to Cure.

Leave the phone resting on something so that the corners are not touching any surface. Leave to cure for 24 hours.

Step 14: Trim Remaining Flash.

Once cured use a scalpel to clean the excess flash from the phone.

Step 15: Complete !

You should be left with four perfectly formed sugru corners that will protect your phone from drops! Enjoy!

Step 16: MakerBot Detail

This is the result from the MakerBot Replicator 2 mold.
You can see how sugru picks up all the detail from the mold.
I love this version :)



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We have a be nice policy.
Please be positive and constructive.




I think sugru has an awesome possibility involved with water. I wonder if you could make fishing lures out of them, because it could be formed on to the hook and would fall off. And in sailing, sugru could be used as stoppers on lines and replacements for lost plugs. Or what about sugru fishing bobbers???

1. You used compression molding. Injection molding is what a manufacturer would use.
2. The cure time is outrageous. That would not be a viable manufacturing process.
3. The manufacturer would not, in all likelihood, mold to the product such as to inhibit the opening of the product.
4. The manufacturer would more than likely use a thermoplastic elastomer, such as Santoprene, that could be injection molded and still have elastic properties that would solidify quite rapidly only having to cool down.

5. Sugru has to "cure" thereby making it a suitable product for the hobbyist.

This is an instructable for the hobbyist who wants to use sugru, it's the sugru channel for Pete's sake.

Is there any reason as to why the parts are not available for purchase from Shapeways? Would love to use these but would prefer to order the parts instead of finding a printer.

I guess they just recently put this up, the link is in the first step.

Or, you can just click this link.

the parts are available to download from thingiverse, you could upload them yourself to shapeways We did post them there but it is very expensive to print the parts as they are quite large:(
You could look for a hacker space in your area?

Hi sugru is not yet available in Canada but we do ship to Canada from Michigin, if you order from sugru.com you should have it in a few days...

Can I get sugru here in Canada? Like is it in michaels? Because sugru looks cool and I want to try it! :D

You're making Fabricator's History, here...
3D Prints for Molds, not finished objects.
The possibilities are endless, not only for Sugru, but for a lot of stuff...
I always thought 3D printing is perfect for Mold-making, then, it's for anyone's fancy to use any Molding method to produce N objects, in a fraction of the 3D printing time.
Went to my Blog:

very good idees for me thank's