Open Source: Making a School Bus Wine Stopper with Blender, Shapeways, and Niles Bottle Stoppers

My mother drove a school bus for 24 years. During the school year she called Friday and Saturday nights “Wine Nights” because she could drink a glass a wine and not have to worry about getting up obscenely early the next morning. Well, after 24 years, she retired, meaning every night could be a wine night!

To help celebrate, I wanted to get her a school bus wine stopper. Oddly enough, there seem to be an absence of products that combine “school bus driving” and “alcohol.” : ) Luckily, that’s exactly the niche 3D printing and Shapeways is for! I designed and 3D printed her a customized School Bus Wine Stopper.

From Model to Reality

I’m still new at 3D Modeling and Blender and by no means an expert.  But for what it is worth, here’s how I made my School Bus Wine Stopper a reality with Blender, Shapeways, and SS Niles Bottle Stoppers. Maybe something out there will be helpful to your projects!

Recommended Best Practice – Don’t Recreate the Wheel If You Don’t Need To
With 3D printing, you often pay by the volume for the material. With that in mind, was it worth it to me to pay more to print the stopper portion? Bottle stoppers on the internet were just a couple of dollars. It would cost me more to custom-print that portion. Purchasing a pre-made stopper also took some risk out of my process as that was one less piece I had to worry about sizing right and fitting with O-rings and all that. An added bonus is the only material (as of this post writing) at Shapeways that is “food-safe” is the ceramics and I knew I wanted my stopper to be in steel.

I purchased Bottle Stoppers from SS Niles Bottle Stoppers. It was already a proven product and manufactured in FDA-grade food-safe stainless steel. They have many different types of stoppers to choose from for different applications.  I used the 302 product which included a 3/8” stud.

#302 from Niles Bottle Stoppers

Recommended Best Practice – Plan Ahead
It really really really helps to know what material you plan on printing in and what it’s limitations are, so you know your measurements from the get go. Shapeways has detailed design recommendations for each of its materials. For my mother’s wine stopper, I knew I wanted steel. I knew from the breastfeeding pendants that it feels solid and sturdy. I also knew the gold plated steel (which happens to be school-bus appropriate yellow) is gorgeous. A rigorous review of the steel materials properties page had me mentally poised that all my walls, all my engravings, etc would have to be 1 mm deep and wide. Knowing that from the very beginning was immensely helpful for the design.

I took measurements of existing wine stoppers and the stopper I ordered from Niles Bottle Stoppers so I knew my dimension of my bus right away. Although it is easy to scale things in Blender, I still recommend knowing your base object size right away. Here’s why– if you do all your engravings and additions and then you size your object up or down– you’re also mucking with the sizes of all your details. So if you had a compliant 1mm engravings and you size it down to 75%, suddenly, you have engravings that are now too short and you’ll have to fix them all.

Recommended Best Practice – Naming Your Objects
My day job is programming and I definitely know the benefits of naming your form elements. I found the same thing to be beneficial in modeling in Blender. I ended up with dozens of objects for my windows and doors and headlights. Keeping the default names of “Cube.001”, “Cube.002”, “Cube.003” would have been tedious to keep up with, so I made sure to give them more meaningful names.

Naming My Objects!

Process – The Bus Base
I started with two “cubes” that I scaled to make the body of my bus. I selected them both and went to Object->Join to fuse them into a single object.

Joining Objects

I wanted to round the corners, but I didn’t want to bevel every single edge, so I got to learn about setting the Bevel Weight for specific edges in order to control how each edge was going to be beveled.

Setting Bevel Weight

And then I went under Modifiers and added a Bevel Modifier.

Bevel Operator

Process – Engraving Versus Embossing
With my details for the bus, I had a couple of choices, I could engrave my windows and doors into my bus base so they were set into the bus body, or I could raise them out of the bus base. At the time I chose engraving. Why? I’m a cheapskate. With the steel pricing at the time, the amount of material was the biggest factor in cost. Everything you engrave out of your design, that is less material and saves you money!

Process – Hollowing the Object
And speaking of saving on material cost, my bus is hollow underneath. There are different techniques to hollowing objects out. With this project, I simply made some smaller cubes and used the Boolean Modifier (more on that below) to subtract them from the bigger bus.

Hollow Bus

Process – Boolean Modifier Crazy!!!
After that, pretty much of the rest of this project was all done through the Boolean Modifier. I did a LOT of subtracting of objects from each other. A lot of it.

The Boolean Modifier is pretty easy. You click on your Base Object and then you click on the Modifiers icon. You select Boolean. Then for Operation, most of what I did was Difference (Subtracting one object from another). Then you select your second object.

Boolean Modifier!

Remember above when I recommended naming your objects? Here’s a situation where is it’s helpful. You aren’t sifting through dozens of “Cube.001”, “Cube.002”, “Cube.003”. Naming your objects makes it easy to pick the right one to subtract.

All my windows, doors, stop signs, were just outer objects with smaller, inner objects subtracted from them. For example, let’s take the school bus door. That was a big cube with two smaller cubes subtracted from it:

The School Bus Door is Just Cubes, Scaled and Subtracted From Each Other

So in the above photo, I start with three objects—a large rectangle and then two smaller ones. I use the Boolean modifier to “Subtract” the two smaller rectangles from the larger one and I end up with my school bus door.

With my end result intended to be steel, I made all my engraving lines 1mm thick and 1mm deep.

Does it look hard? Well, as proud as I was of my handiwork, it’s not hard. In fact, after I finished my modeling, I discovered this technique of making your object out of a bunch of little objects is prominent in a 3D printing tutorial for CHILDREN. CHILDREN! So if I can do it and children can do it, you can do it. : )

Quick Tip on Object Sizes And a quick tip. I initially made this mistake and I’ve seen others on the Shapeways forums make the same miscalculation. When you are making your object sizes, it’s easy to think, “Oh, my minimum wall requirement is 1mm, so I want my outer object to be 1mm larger than my inner object.” That’s not necessarily the case because you are likely making more than one wall. Take, for example, my cylinder to hold on to the Wine Stopper stud. My outer cylinder has to actually be 2mm wider than my inner cylinder– because I’m going to have TWO walls. I want them both to be 1mm thick for steel. Gotcha! You Have to Account for TWO Walls

Continuing the Boolean Modifier craziness, once I made all my windows and doors and headlights and grill lines, I used the good ole Boolean Modifier again to subtract (aka engrave) those items from my base bus body.

And the same went for the text at the top of the bus.

Getting Ready to Engrave My Text

Quick Tip With Engraving Text—I’ve found it to work better if I convert my text to mesh and then extrude it. The normals of the faces work out better for the Boolean Modifier Difference operation.

Process – Fixing Thin Walls
When I was ready to try my model out on Shapeways, I went to File->Export and saved it as an STL file. When I uploaded my .STL to Shapeways, however, their checks indicated that I had some thin walls with the “A” in my engraved text. I fixed that by manually moving vertices around and uploaded a new model.

Fixing the A

Math – Making the Stud
I’ve only been 3D modeling six months or so and I’m finding math to be quite valuable. A good example of this is fitting my bus on the stud for the Niles Bottle Stopper I purchased. The stud itself is 3/8” in diameter. I work in millimeters, so I just used Google to figure out the conversion.

Converting Inches to Millimeters, Thanks Google!

So basically what I wanted was a nice little cylinder to fit over that stud. If I was going to error, I would want my hole to be TOO big. I could always fill it with adhesive or Gorilla Glue. I didn’t really want my hole to be too small and put myself in a situation where I would have to drill it (or rather ask my husband to drill it) to make it fit.

Now, looking at the material page on Shapeways, I noted steel does have a margin of error.

Steel’s Margin of Error

3/8″ == 9.525 millimeters. To calculate the margin of error, I multiplied that by 0.01 (1%) and added 0.1 to it (per their accuracy statement). Since there would be TWO walls (one of each side of the cylinder) that could affect my fit, I multiplied that by 2.

The meant I would probably want to increase my cylinder opening by 0.3905 mm to account for possible margin of error. I went ahead and rounded up to 0.5mm just to be safe (And again—I would rather my hole to be too big than two small)

Behind the Scenes Glimpse of my Notes

I decided my hole would be 10.025. So my inner cylinder had a diameter of 10.025. I wanted my walls to be 1mm thick, so I made my Outer Cylinder 12.025 in diameter (remember there are two walls). Then using, you’ve guessed it, the Boolean Modifier, I subtracted the inner cylinder from the outer one.

Outer and Inner Diameters

So get this—either I had beginner’s luck or my math was solid. My steel school bus arrived and the stud attachment was PERFECT. I had to tap it gently with a hammer to place it on the bottle stopper stud and there it has stayed nice and snug. No adhesive necessary! Score!

Note: If you are modeling for Niles Bottle Stopper #302 and you plan to print in the Strong and Flexible plastic, you may want to choose different diameters. I’ve found the plastic to fit looser and require glue.

Prototyping and End Product
Before diving into the more expensive steel, I did print a version of the School Bus in cheap (and fast) White and Strong Plastic. It looked great (other than I shorted my Mom’s service years by 1), so I changed “23” to “24” and ordered a version in Gold Plated Steel. It arrived just in time for my Mom’s last day of school!!!

Prototype and Final Product

And the end product was a hit! I think I got myself one notch closer to being my Mom’s favorite child. : )

School Bus Wine Stopper

And if you happen to covet a School Bus Wine Stopper of your own, you can order one to be printed from Shapeways (I have the Personalize option turned on too). Also, I’m a big believer in Creative Commons, so feel free to download the model for your own projects. Just don’t forget that Attribution clause! 🙂

Happy Modeling!