Restraining Bolt

CS:L & Arri-Type MC Modified Version

If you joined the R2BC before 2011, you might think there was only one Restraining Bolt. This is the CS:L Restraining Bolt.

Click on the image to open a 3D .pdf version.

You can download a model of the CS:L Restraining Bolt from the Astromech 3D file Droidwiki:
On 7/31/2011 Cole Horton Posted the thread "Droid Restraining Bolts - part found!" which provides some of the details of the search that he and Chris Reiff conducted to find the source of the part used in the Movies.

That was followed by Chris posting the Part thread "RESTRAINING BOLT Arri-Type" on 5/21/2012

I first became aware of it when Chris made a presentation at DroidCon II (8/2-8/4 2013)

In addition to the image above, with some dimensions, they also posted this drawing in the part thread. For a while I played with the cross section, turning it into an Autocad drawing and scaling it using the dimensions from the background artwork. I wasn't happy with the results so I let the project go dormant.

After reviewing the parts presented on my 3D models page I decided to update this Arri Bolt page.
Checking the R2BC Forums I discovered Sigge's thread "3D printed Restraining Bolt Arri-style with STL file". I'm guessing that Sigge followed the same approach as I did to create his 3D model.

Out of curiosity I downloaded the .stl file. But I was disappointed when I discovered that there was no detail on the underside of the model! That's partly a consequence of it being printed as one piece. 
As a result, I decided to revive my work on the 3D model. The second time around I tried out a piece of software called "Scan2CAD" It was relatively easy to use and gave good results. Of course, since I was working from the cross section there is no knurl on the part!

Using that model as a starting point, I added the missing knurl, and then made some additional changes. To make it 3D printable I segmented the full model (below) into a front half (green)  and a rear half (red). I also included an M8 Carriage Bolt and mating Nut to the model.  

After a discussion with Michael Paul, K&J Magnetics, Inc. about the various options for holding the Arri Bolt to a styrene Droid with a .08 thick skin. I decided to use his suggestion of
a DF03 magnet in the recess at the rear of the bolt and a stronger DF2 magnet behind the skin area where the Bolt is going to be attached. In order to be able to remove the magnet from the restraining bolt (even after it's glued in!) I added 4 slots to the recess which was enlarged slightly to fit the DF03 magnet.

Click on the image to open a 3D .pdf version.

And Now For First Prototype results!

The two halves of the MC Arri-Type Restraining Bolt!

[ignore the dirty bits - I'll get a new image soon]

The carriage bolt comes with a Logo on it's surface. For now I'm grinding it off with a Dremel sanding drum.

Parts bolted together

Glue added to hold magnet in place.

Magnet Installed

Removing magnet using a scribe.

Assembled bolt

Assembled bolt sticking onto R2!
I've decided to include the hardware and magnets with this 3D printed part to save the builders from having to buy multiple parts from different vendors. The package includes: 2 Pc 3D printed Arri Bolt, 8mm Bolt & Nut & 2 Magnets.
For my 3D Printed Parts Price List click here