Among many things that I wanted to make big, I decided to make a giant pencil. I quickly modeled one in Rhino, strongly believing that I shouldn't encounter much difficulty printing its parts with the ShopBot. Above is an image of my 3D pencil model. In each image, left model is the assembled version while the right ones are segmented individual pieces that I needed to print. For the top part of the pencil, I decided to cut out a number of circles and stack them up to create the eraser.

For printing 3D models with ShopBot, .stl or .dxf format was the best. I imported my file, which was in .obj into Meshlab and saved it as an .stl file.

Images above is the flattened version of all the parts needed for my giant pencil. One thing to make sure when printing 3Ds in 3D ShopBot is that every pieces have to be on the same plane and that there must not be any undercut components. ShopBot will get confused if this is the case.
I basically had to flip most of my pieces, especially the components for the eraser part of the pencil.

Top left image is the path that I was able to create from siliced pieces (from 123D). I had to erase the vector paths for numbers that automatically came from slicing my model in 123D. I sent the job to the printer and it took about half an hour to print all 82 pieces! I sanded down sides of each piece. I also got some paints from an artist supply store in hopes of making my pencil look real by painting it!

However, as always, getting the machine to do the job that exactly you were looking for was not easy. When I imported my .stl model to print the pieces, it was not read in the way that it was supposed to and would greatly distort the pencil's look, which I did not want.
Sophia Brueckner, the TA who helped me, suggested using Autodesk's 123D. She quickly helped me import a 3D pencil model into 123D and slice them into pieces that I can stack up to make a pencil.

* Again, thank you so much Sophia for helping me the other night! You are AWESOME! :)

Here is the final result of my pencil!

Although it is made in a way that was quite different from my original intention (which would have create more neat and nicely looking pencil), I was super happy with this one!

I put a real think charcoal at the end of it so that I can actually write and draw with it. I tried drawing a simple smiling face as you can see in the picture. The pencil is about 110cm long and although I didn't get a change to weigh it but it was quite heavy. I was able to draw with it easily though :D

WEEK 5: MAKING A GIANT PENCIL!!!

Part1: 3D Modeling & Planning

Printing & Assembling Parts