This is the first in our series of guest blog posts, showing off our Makers for Dayton Mini Maker Faire. Lory Livezey runs the Tinker Tuesday Meetup Group, is a partner in STEAMWorks K12 and K12 Gallery Tejas and is a web developer for MCM Electronics.
Recently, I have been focusing on finding some fun projects for my Tinker Tuesday Meetup group that will introduce people to the amazing Maker world. Since I recently purchased an ISense 3D Scanner that attaches to/ my IPad, I began scanning people at the K12 Gallery where I usually hold my Meetup. Technology at an Art Gallery is an intriguing proposition — holistic creations — so I’ve been trying to find Tech-Art cross-over projects.
Here are the materials I used for this project:
— 3D Scanner
— MeshMixer (AutoDesk)
— 3D Printer (with software)
— Glue Gun
— Plastic Cups (see-through if possible)
— Food Grade Rubber Mold Making Compound
— Rubber Gloves
— Exacto Knife
Scanning the Person
The first step is to scan the person. I found that its best if they sit in a chair, particularly if they are taller than you. You will need to get the top of their head. The scanner will lock on to the target, and the ISense uses the motion sensors in the IPhone/IPad, so you will need to move — do not try to move the object. As you complete the scan, the object (person) will turn white. Get under their chin, behind their ears, etc, or else you will have holes in the model.
Touching up the Model
The ISense software will allow you to e-mail the model. You can then pull it up on a PC (or Mac) and I did the touch up using AutoDesk MeshMixer. Here are a couple of useful commands:
- Auto-detect the holes in the model and fix: Analyze -> Inspector -> Auto Repair
- Move the model around: Edit -> Transform -> Drag the arrows around
- Make the Model a Solid: Edit -> Make Solid
- Fill any holes: Sculpt -> Drag the surface over the holes– pretend it’s clay
- Make the bottom of the model a clean cut: Edit -> Plane Cut -> Drag below plane
Bring Into 3D Software
Once you get the model cleaned up in Mesh Mixer, you’ll export to an STL to pull into your 3D printer software. Mine came in really tiny, but I used the Scale tool to enlarge it to about 2″. After some experimentation, I found it was best to do a high quality print with a high layer density (.15), but since it doesn’t need to be strong, a low fill (about 20%). It took about 4 hours to print, but it came out nice and smooth! The 3″ models I used for other purposes took about 7.5 hours.
Making the Mold
The next step is to make a food-safe mold. There are a couple of things to consider. As with 3D printing, you have to think about overhangs. How will you get your object out of the mold? Straight objects work pretty good in a one piece mold, but for a complex object such as this, it’s common to make a two part mold. My original plan was to do it the “right” way and create a two part mold like this:
The frame is filled half way, allowed to cure, then flipped over (removing the clay), pouring the second half, using a special spray to ensure that the two halves do not stick together. The screws are what I used for guides so that the two halves would fit together.
I ditched this idea because I want the class i’m developing to be simple. It’s all part of the process of making — trial and error and error and trial and eureka!
The method I decided to use involved a cup and a method used for one part molds. I hot glued the model to a piece of foam board (found at WalMart in the crafts), and cut off the bottom of the cup.
Mix equal amounts of the A and the B parts of the rubber mold mix. Pour it in slowly, holding it high and off to the side of the model. This will allow for the bubbles to dissipate.
Allow The Mold To Cure
Allow the mold to sit for 24 hours.
Remove the Object
I knew I was not going to be able to pull the object out of the mold. Instead, I used an exacto knife and cut the mold in half, pulling the model out.
Pouring the Chocolate
I put the two pieces back together and tied rubber bands around them, making a seal. After heating the chocolate in the microwave for about a minute, I poured it into the mold.
Here is the final product, compared to the model:
My disclaimer is this: This is not the usual way to make a 2 part mold, but as you can see, my customer was delighted and it works. So I guess that’s what matters!
Check out this video of Marysa unbanding her chocolate: https://youtu.be/SBfOAdxI_KA
For more fun projects like this, please join my Tinker Tuesday Meetup Group. Proceeds from this event will go to STEAMWorks K12 and K12 Gallery Tejas. I am also a web developer for MCM Electronics — a supplier of Raspberry Pi / Arduino and other electronics for the Maker Community.
See you at Dayton Mini Maker Faire!