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I’ve been cooking with fresh spices since the day I learned to fry an egg. Nothing beats fresh basil as a topping for pizza, or snipped fresh coriander to dash a warm bowl of curry. The downside though of fresh spices, is if you buy them packaged from the supermarket, it only takes a few days in the fridge for them to start looking like this:

So, it has been my dream for a while to build a small house for these guys to grow in that could fit in an NYC micro-size kitchen. I started out by sketching a few design ideas. I have a fetish for modular furniture, and this seemed like something that could potentially be stacked one on top of another. However, after speaking to Ben about this project, an idea come up to make half a green house, so that two halves would make the full greenhouse.

 

The materials I thought would be good to use were plywood and clear acrylic for the windows. Glass crossed my mind as well, but since I envisioned making holes on one of the side for the plants to breathe, I thought acrylic would be better. Here are the parts I planned for cutting on the CNC:

After planning these out, I went to get some wood and start cutting these parts out!

Once the wooden parts were cut, it was time to make the acrylic parts that would sit in flushed to the pockets created in the wooden frames.

 

 

Once all of the parts were prepared, it was time to assemble everything together! But before gluing the wooden frames together, I wanted to make sure the sides would be super-durable, so I drilled holes for wooden dowels on the sides. This was done by using a dowel jig, so that the hole for the dowel is created directly in the center of the plywood frame (and, the wood doesn’t split!)

 

Once those holes were drilled, the glue went on, the dowels went in and the clamps held everything together. After screwing on some last bits, my greenhouse was finally born!

Two weeks ago we were given the challenge to create joints that connect with one another. This might sound like a trivial task (it did to me in the beginning), but actually, it’s not. When creating pieces that are meant to fit together, it’s important to remember that even though in theory it makes sense that these two pieces will just naturally fit into one another, in reality they most likely will not.

 

Every material has a different tolerance, which means that every material will need a different negative space for the positive piece that will be inserted to it.

This is an sketch of what I attempted to make:

And, ideally, I wanted these joints to be possible:

The material I used was plywood, so I knew that I would have to make the hole a bit bigger for the piece to fit in. Assuming this would be my biggest issue, I went ahead to view my file on MasterCam, however, the preview kept showing me problems if I were to go along and cut my file on the CNC. All the issues I was having had to do with misinterpreting the path of the drill bit and it’s abilities to produce straight shapes as opposed to rounded corners. This is a bit hard to envision at first, because when we think of cutting a straight line, that’s usually a very trivial task. With the drill bit though, you always have to remember that it can’t cut anything with sharp corners, because the bit itself is actually a tiny circle. So, areas like this are virtually impossible to cut using the drill bit:

 

So since those corners actually came out rounded, you can imagine that it is impossible for the rounded corners to lock into the joining parts where the corners there are sharp. Conclusion? The design should have round corners everywhere. By the time I had realized this it was a bit late to cut these again, so I ended up sanding the corners down:

This ended up taking a lot longer than expected, but the pieces successfully linked together!

 

Last Friday, Ben showed us an example of a project done on the CNC machine. He kept referring to as a donut. This is what it looked like:

The more I kept hearing the word “donut”, the more I wanted to try to make one using the CNC machine. And here’s how I did just that.
 

Materials and Programs

Before materials, I just want to mention that it’s great to work on this kind of stuff with friends — especially if the is a new area (like it is for me). I’ve been working with Maya Tal and Ainsley O’Connell these past few weeks and it’s been great!

So, back to materials. For this project we used plywood, a 1/4″ bit for the CNC, the CNC machine, and a bunch of new programs: Vectorworks (which is a Computer Aided Design = CAD program), MasterCam and the Techno CNC Interface. I’ll be completely honest, I don not like Vectorworks at all, and I have a hard time understanding why Illustrator can’t be used instead. It’s ok to use when drawing basic geometric shapes, but what if you want to create a squiggly, rounded shape (the icing of the donut)? Even when using a Wacom pen, and even though there’s a tool for drawing free-form shapes in the program, smooth, rounded lines just doesn’t seem to translate well at all on Vectorworks. So, for the icing shape of my donut, I imported an Illustrator DWG file and spent some good time cleaning it up so that Vectorworks would like it.

 

Once the files are completed in Vectorworks, they are exported and opened (on a PC!) on MasterCam. MasterCam is the program used for defining the width of the material, the bit size that will be used in the CNC machine, and the cut / pocket on the material. Setting the direction if the job on the contours is super critical, and there’s rule you must always remember:

Counter-clock wise → In

Clock wise → Out

Once the settings are all in, MasterCam will show you a quick animation of the job.

Finally, last destination before the actual CNC machine starts working — Techno CNC Interface. This is a pretty simple past, basically this is where you pull up the file you have prepared, and set the origin point for the CNC router to start it’s job. But, before even touching the computer here, we first needed to set up our material and mount it to the CNC bed.

Once everything was mounted correctly and there were no loose areas, we could make those last setup commands and get the CNC machine running!

 

The CNC Monster Machine

This machine is nuts. I think the biggest surprise was how fast it is as opposed to The OtherMill from last week. Here’s the beast at work:

 

And here’s what I what I got after the CNC job was complete:

I was so happy with the results from the CNC, I didn’t think the result would look like this. From here there was only one thing to do — PAINT!

But again, before jumping to paint, there was a minor detail I had to take care of. The sprinkles didn’t fit perfectly into the pockets I made for them (I didn’t cut through the plywood completely, I left some material in order for the sprinkles to be a bit elevated). Ben suggested that go back to Vectorworks, make slight adjustments, and cut new sprinkles in the CNC. I should have listened. Instead, I thought that hand sanding them would be enough and that the acrylic paint layer wouldn’t be that significant. At the very end, I used a hand dremel to sand the edges of the bottom of the sprinkles, and had to hammer them in. Note to self: listen to the pros next time!

So, paint. This was a lot of fun. I picked up some primary acrylic colors down the block and started mixing them to get the cartoon-y colors I was looking for:

And with the help of some wood glue here and there, we have a donut!

This week I became familiar with “The OtherMill”, which is essentially a mini CNC machine. The OtherMill is great for small, precision work, and can mill pretty tough materials such as aluminium (which is what I milled this week).

The Other Mill Became Ill

My first trial on the machine did not go so well. Before I describe what went wrong, I’ll give a quick overview on how the machine works. The OtherMill is a routing tool, so it works with bits. These bits engrave or cut the material that you load according to the SVG file that you send. You can also control the depth of engravement and play around with that, which I think is pretty neat. In order for this process to work, the machine has to “calibrate” the settings every time a new job is set. Part of this calibration includes making sure the actual bit knows the distance between it’s initial point and the material, otherwise, it will not be able to do the job.

On my first round using The OtherMill, everything was indeed set up exactly the way it should have been, but, something interesting (and unfortunate) that happened was that during the actual milling, the bit itself start to slip a very tiny bit, creating a lag in the job. Here’s the thing about The OtherMill — if you start the job and set an engravement for 0.016in, it will do that engravement as far as it’s concerned. The OtherMill doesn’t know if the bit is lagging in the middle of the job, so you can imagine that this could consequently meaning that the engravement will be deeper than you had intended it to be in the first place. And that’s exactly what happened in my case; I set a cut, the bit slipped a tiny bit in the middle of the job, and as a result, started cutting the bed of the machine (once it had gone through the aluminium).

Second Trial: Successful Comeback

After getting a good understanding of how delicate and precise The OtherMill is, I was ready to get back on the horse and giving the milling a second try. Read More