Category: Vocational Education

Posted on

Arduino Holder Project

Today I’ll talk a little bit about setting up a part for use on our Tormach PCNC 1100 mill. As I said in a previous post, I’m working on a new project for students, creating a custom arduino holder out of aluminum. I’ve been documenting the process of preparing the stock for the mill.

The project as designed in CAD calls for a 0.8 x 2.6 x 3.2 in block of aluminum stock. I’ve cut a .9″ thick piece of stock from a 6 x 4 inch block and then roughed it to down on the bandsaw to get it close to the dimensions I want. Next, I took it over to our Trax mill and faced off all sides until it was milled to the dimensions mentioned above. I probably do not need to be this precise, but its a good exercise, and will give the students a good beginning in using our manual mills.

Once the block was ready I took it over to our Tormach machine and proceeded to zero out the X, Y, and Z coordinates. This is extremely easy using the Heimer – a measuring tool that provides the zero, or edge, coordinate without the user needing to to any math as might be done with a standard edge finder. See video below.

This project requires a part flip, and for the first attempt, I tried using the same X and Y coordinates – which did not work out. Mostly because the Y coordinates did not match on the flip. Another issue I had was tapping the holes. I did not properly set the RPM and feedrate correctly for the 4-40 tap, and it broke immediately. A silly mistake, but one that will be easily fixed next time I run the job.

There are some photos and videos below of the process, although I forgot to take a photo of the finished product. Will update on the project next week.

Posted on

Milling

Today I started milling a part that will become a student project. The idea is to have each student learn how to mill their own Arduino holder. The holder allows for easy prototyping, and will give them hands on knowledge of how to use CAD and CAM to to setup a part.

The CAD aspect of the project utilizes a spec sheet in order to get mounting hole dimensions for the Arduino. Students will learn how to import a canvas into Fusion 360 and calibrate the canvas to the correct size. Next, students can build their holder directly on the canvas. Additionally, the CAD project requires importing components from McMaster Carr, and then using the CAM features of Fusion 360 to create the tool paths on two sides of the part. Lastly, the holder requires a laser cut top. Here is an image of the project below.

 

I was able to setup the CAM today and began cutting stock to size. This process started with making 3 cuts on our vertical bandsaw to a large piece of aluminum stock and then placing the stock on our Trax mill to get more precise with the stock dimensions. I am looking for a stock size of 3.2 x 2.6 x 0.8 inches.  Below are some images of cutting the stock.

Posted on

Internet Radio

A while ago my wife surprised me with an old fashioned radio. It’s an Emerson 805 Series B model which was available in the 1950s. The radio does not work anymore, although all its guts were still intact, tubes and all. I decided to turn the radio into a working internet radio, and hoping to keep functionality of the tuning dial and power switch. 

So far, all I’ve managed to do is take the radio apart. A lot of interesting components inside, but for my purposes I will only keep the plastic enclosure and tuning and power knobs. The back needs to be recreated, which I will do with the laser cutter, as well as inner speaker lining. Not sure what I will use for that, but it can be attached to a lasercut support structure. 

For the electronics, I will initially be following a guide from Instructables – this one I found from _Marcel_ which looks very close to what I’d like to accomplish. In addition to new electronics, I’m also going to clean and repaint the enclosure and knobs, unsure of the color scheme right now, but I will want to keep a retro look to the radio. All for now, a few photos of the radio below.

Posted on

COVID Testing

A new addition to this school year has been the weekly COVID testing. The school has tried to break up testing into groups for each period of the day to minimize wasted class time, however, teachers often fail to adhere to their specified time, and when this happens it causes a backup in the line, which leads to long waits for students and faculty to get their testing done.

Especially during this time of year, where COVID cases are on the rise post holidays and with the Omicron variant, the school has opted for individual testing instead of their normal pooled testing. I understand the decision, it’s a quicker way to find out who has tested positive and to keep those people out of the building. On the other hand, it can take a lot of time away from students during the school day. Luckily for my group of students today, the three time slots we had schedule to do testing worked out perfectly, zero waiting in lines, and we were back in the classroom working after only a few minutes.

I don’t see an end to COVID testing this school year, and have a feeling it will remain in place in some form at the beginning of the 22-23 school year as well.

Posted on

Volume Control | Parametric Modeling

One of my favorite aspects of my job is solving a problem we have never before encountered. Luckily, this happens nearly every day as students are building various types of projects of their own design, such as candy shooters and singing toothbrushes. 

A senior was having problems building a box for a bluetooth speaker setup they were working on, as they were trying to understand how to build the box with the proper volume specified for the speakers he was using. He was taking measurements, putting them into CAD, but when things changed within his project, he would have to change all his dimensions again and it was a real tedious task. 

Working together we were able to solve the problem using parameters in Fusion 360. We utilize Fusion 360 for all our CAD needs in the classroom. It’s an easy to learn, robust software with built-in CAM that enables us to send our models to all the different machines we have in the shop – 3D printers, waterjet, plasma cutter, mills, lathes, etc. It’s also free software, and I have the ability to setup an educational account and give access to all my students, rather than having each student setup their own personal account. I really like the way they have the new educational account setup for teachers and students, makes life much easier than before where students needed to verify their accounts which was often problematic.

Back to the parameters discussion. By utilizing parameters in Fusion 360 along with an organized modeling strategy, we found a way to control the volume of the box so it always remains constant, even when we change the length, width, or size of material. Below is a screenshot of the parameter setup for the project. You’ll notice some odd math happening, as there are several instances of multiplying 1 in within an expression. This is because Fusion 360 does not have in² or in³ within its parameters framework, so you need to use the 1 in to cancel out parts of an expression so it has the same units Fusion 360 can work with. 

I went ahead and created a quick modeling video for students, so in the future I can just point them to the video instead of showing them directly, which frees me up to help other students in our classroom. Video below.