Introduction: A 3D Printed Model Car Display Case

About: I'm a Mechanical Engineer turned IT Professional and Author. I came into the Information Technology world because someone challenged me to. But at heart, I'm still a grease monkey with no desire to lose touch …

Okay! I use what little I've learned about 3D printing in the past 2 or 3 years to solve some practical problems around the house.

This way I get to keep the establishment happy and spend more time around 3D printing without causing domestic unrest!

In this IBLE I will show you how I designed and 3D printed a display case for my small collection of model cars.

Let's get started.

Step 1: The Problem ...

I have a small collection of model cars that is gradually running out of space on the topmost shelf of my hutch. It's at the point where the cars are beginning to fall off the hutch almost every time I retrieve other items from the shelf.

Something had to be done to address the problem. That said, I didn't want to pick up a traditional display case from a hobby store and put all my cars in there.

That would be too boring.

And lazy!

Besides, I needed to test the limits of my favorite 3D printer, the Creality CR-10.

Step 2: The Design Process

Taking on the design process was a bit tricky at first.

Therefore, I decided to begin by dividing my collection into a few groups roughly based on the dimensions of the cars:

Group # 1: Tiny - Length x Width x Height appeared the smallest

Group # 2: Small - The Length was much larger than the Width and Height

Group # 3: Medium - The Height or Length was much larger that the other 2 dimensions

Group # 4: Large - All bets are off, this group stood apart from test of the crowd!

The second picture illustrates the idea.

Once the grouping was done, I measured the L x W x H dimensions of all the models.

Step 3: Setting Design Limits to Test Limits

Display Case Dimensions:

With the measurements in hand, all I needed was to set a limit on how large my display case was going to be.

I've seen several videos of the Creality CR-10 printing large vases online. But I'm yet to see one that printed models that ran all the way to the edges of the bed.

Which gave me an idea!

How about I fix the Width and Height of the case to fit the 300 mm x 300 mm bed dimensions of the CR-10?

This way, I get to limit my design, and at the same time test the limits of printing a model that takes up almost the entire bed area of the CR-10.

Armed with this thought, I set up a rough 2D template of how the display case would look like. This brought the L x W of the display case to approximately 256 mm x 253 mm.

Why not a 300 x 300 Display case?

Well, that's because there would be no space to attach the clips that would hold the glass plate to the heated bed! I can orient the 300 x 300 model vertically, but that means too much of raft supports leading to excessive consumption of PLA filament.

The Shelf Dimensions:

Based on the measurements of the 13 model cars, I was able to arrive at 3 general sets of dimensions for Length and Height (vertical space between the shelves) to accommodate all the four groups. This would keep the design from getting too many shelves with a variety of measurements.

The width however was a different story. Some of the models were extremely narrow in width. Therefore, having a uniform width for the display case although an easy option, was not a good one. This made the narrow models look too awkward on large shelves.

Display Case Mounting:

The way the case is designed, it can either be placed on a flat surface or mounted on the wall with the four mounting holes provided at each corner.

Step 4: 3D Print Layout

CAUTION: Very large prints such as this one can interfere with the position of the mounting clips for the glass bed! Test model position in your slicing software and exercise caution before starting the print to prevent damage to printer!

One challenge that resulted by cutting the design so close was to make space for the clips that hold the Glass surface to the heated bed.

The visual shows the 3D print layout and the print settings. The model had to be adjusted in the front-rear direction to fasten the clips in way that the print nozzle wouldn't run into one of the clips resulting in damage to the print head.

Using Transparent White PLA Print Material:

I decided to use the 1.75 mm Transparent White PLA material from Hatchbox for the following reasons:

  • The models are of different colors - a transparent White material will be a neutral match for all cars regardless of their color
  • In the future, I plan to add background LED lighting to the display case - a transparent White material would be the natural choice for such an application

Print Bed Adhesion & Delayed Glue application:

Surprisingly, the PlaySkool Triangular glue stick I picked up from Family Dollar turned out to be extremely effective in adhering the print to the bed for 40 long hours!

The triangular shape of this glue stick gives it 3 sharp edges which makes it extremely effective in applying glue even after the print has kicked off. The last image shows, how I was able to apply quick (Pink) streaks of glue in between the lines laid out by the printer.

Applying glue this late in the printing process prevents it from degrading, making the raft adhere to the print bed during the entire duration of the print - almost 2 days in this case!

Step 5: The Completed Print

The visuals show the completed print. Accounting for the Raft layer, the print took 40 long hours to complete (9:33 PM on Thursday to 2:30 PM on Saturday) whilst the time estimated by Cura was close to 38 hours.

The print quality turned out to be excellent. However, the mounting hole closest to the bottom left, near the HOME position of the printer had excessive stringing and requires some clean up.

Dismounting the Print:

Given the awesome adhesion, this was a nerve wracking experience. The display case does not have a spine in the center. Therefore, I had to be uber-careful in peeling the print of the bed without breaking it!

Dispatching the Raft Layer with Dignity:

Most often than not, the Raft layer is discarded. In this case, I used a marker pen to mark the position of the mounting holes on the Raft before separating it from the print.

I will be using this Raft as a template to drill the mounting holes when I finally mount the display case on the wall. In the process, the Raft will prove more useful that it's intended purpose before it's discarded!

Step 6: The Before and After Pictures!

Finally, the before and after scene!

As seen from the pictures, the display case has dramatically improved my situation as an amateur 3D printing enthusiast.

All the 13 models fit as I had expected. The smaller models start at the top shelf, and gradually build up to the larger models on the lower levels.

As with one of the design goals, the case can be put on a desk (not recommended), or mounted on the wall.

What next?

  • The next step is to design an outer enclosure to enclose the case and also integrate LED Lighting
  • Work on a future version that would have space to incorporate LED lighting
  • I have other model cars that are much larger - now that I know what my printer can do, I can take those designs on with confidence

I hope you enjoyed this IBLE. Happy printing!