Comparing The AMT 1:650 TOS Enterprise Deflector Dish Assemblies With A 3D Printed Version

Hi, Everyone!

I started a project to make a more accurate deflector dish assembly for the AMT / ERTL / Round 2 1:650 TOS U.S.S. Enterprise model kit.

Back in the early 1970s, AMT changed the tooling of their 1:650 U.S.S. Enterprise model.  Although the kit itself from its original 1966 tooling had its accuracy problems, the changes made in the early 1970s created even more issues.  One of the issues was the deflector dish assembly:

• The housing was changed / simplified where the outside wall was raised higher, the inner three stepped rings were all made the same height as the outside wall, and the three "extrusions" from the secondary hull were added.
• The dish assembly was changed from an overly large dish with an equally overly long stem to a detail-less pie pan looking dish with a shortened stem.

 

When the Smithsonian put together the team for the 2016 TOS Enterprise 11-foot filming miniature restoration project, Gary Kerr - Star Trek historian and filming miniature information archivist extraordinaire - was asked to be part of that elite group.  Gary has studied the filming miniature for decades and has worked many times with Polar Lights and Round 2.  After the Smithsonian restoration project was finished, Gary wrote up several articles to share his findings.  One of those articles included a detailed schematic-type cutaway drawing of the deflector dish assembly.  So with that, I decided it was time that the old AMT 1:650 TOS Enterprise kit finally gets 3D printable accurized parts for that section of the ship.

Using Gary's drawing, I created the following:

• Correctly shaped housing with three stepped inner rings, all of which are of the proper heights and scaled thickness.
• Correctly sized dish with accurate details and proper stem height.

 

Without further ado, here is my comparison...

These are two original AMT kit parts for the deflector dish assembly.  The one on the left is from the 1966-era tooling.  The one on the right is from the early-1970s re-tooling.

 Here is a view of the housing by themselves.

Here is a close-up of the 1966-era deflector dish assembly.

Here is a close-up of the 1966-era deflector dish assembly housing.  Notice the three stepped rings.

Here is a close-up top-down view of the 1966-era deflector dish as it sits in the housing.  See how its diameter completely covers the housing.

Here is a close-up of the early-1970s re-tooled deflector dish assembly.

Here is a close-up of the early-1970s re-tooled deflector dish assembly housing.  Notice the three inside rings are no longer stepped and their heights match that of the housing wall.

Here is a close-up top-down view of the early-1970s re-tooled deflector dish as it sits in the housing.  See the lack of detail on the dish surface and how its resembles a pie pan.

Here are the various 3D printed prototype parts that I made.  From left to right: the housing printed at 0.2 mm layer height, the complete assembly printed at 0.2 mm layer height, the complete assembly printed at 0.1 mm layer height, and the dish itself printed at 0.1 mm layer height.  All of the parts are from a filament 3D printer using white PLA plastic.

Here is a close-up of the 3D printed deflector dish assembly housing.  Notice the three stepped rings.

Here is a close-up of the 3D printed deflector dish assembly that was printed with a 0.2 mm layer height.  The parts are thin so at that layer height there are noticeable errors such as the inability to produce the scribed circle detail on the dish surface.  Also, there are multiple holes along the edge of the raised circle on the dish surface.

Here is a close-up of the 3D printed deflector dish assembly that was printed with a 0.1 mm layer height.  With this lower height print setting, the scribed circle detail on the dish surface was able to be produced and there is no missing filament along the edge of the raised circle on the dish surface.

Here is a close-up view of the 3D printed deflector dish that was printed with a 0.1 mm layer height.

Here are all three deflector dish assemblies compared together.

Here is the early-1970s re-tooled deflector dish assembly resting in place on the secondary hull of the AMT 1:650 TOS Enterprise model kit.

Here is the 3D printed deflector dish assembly resting in place on the secondary hull of the AMT 1:650 TOS Enterprise model kit.

 

Because of the relative small size of being at 1:650 scale, I did not do the following:

• I did not model in the hinge assembly that is part of the dish stem.  Since this part is thin to begin with, I chose to sacrifice accuracy in order to maintain thickness for better part strength.
• The surface of the deflector dish features three concentric circles.  The one closest to the center is raised while the other two are scribed.  I did not model in the outer-most scribed ring as it is very close to the outside edge of the dish and doesn't add too much detail at 1:650 scale.

 

Overall, I'm very happy with the results.  The fit is very spot on, and the accuracy to the 11-foot filming miniature is about 95% there.  Printing the parts with a filament printer yields okay results, but all this would probably really shine if it came off a resin printer.  In any case, I hope you enjoyed this comparison.

Happy modeling...and printing!

:)