IOT Candy Scale

I’ve been thinking about building an internet enabled scale for years now, and recently, I finally got around to building it. Sure, there are plenty of WiFi scales these days, but I wanted one that automatically took a measurement every few seconds and uploaded it to the internet where a website would display a continuously updating chart. I suppose a product like that exists, but I thought it would be more fun to make it myself.

The electrical components came from SparkFun. They make an OpenScale board that did almost everything I needed when connected to a load cell. The board was already programmed to have all the features I needed for calibration and taring the scale. Originally I had planned to hook that up to a WiFi-enabled Arduino or Raspberry Pi, but I kept it simple and just plugged it into my computer. The computer ran a simple program that I wrote to communicate with the board and get a reading every 30 seconds. Those readings were uploaded to a SQL database in Azure and then I wrote a website that used the Google Chart Library to display the measurements.

There are a lot of technical terms in that last paragraph, but it was mostly just plugging together a bunch of components to make the solution and I had it finished in a couple nights (after a lot of research to find all the components!) I mounted the load scale on a piece of plywood and connected a bowl to the top of the load cell. Voila!

The scale made its debut at work to celebrate my 12th anniversary at the company. You can see the live website at It will always show the data from the last time I had the system set up and running. I’m hoping to try it again at Halloween.

Fun With Vinyl

I’ve been having a lot of fun with the Cricut that we bought as a family Christmas present. I bought a roll of vinyl and transfer tape, and I’ve been having fun experimenting with them. Below are a few photos of things that I’ve drawn and cut. I realize that some of them won’t make sense because they are random words from projects at work, but it’s still neat to see how cleanly and nicely these come out. I have access to a large-format vinyl cutter at work, but it’s a lot easier to experiment and learn with the Cricut at home. Plus, all of the drawing work that I’ve done for the laser cutter in the past transfers very well to being cut out of vinyl too.

Laser Cutter Puzzle

The idea of making a custom puzzle has always intrigued me. I’m partially interested in the computer science problem of generating an random puzzle with an arbitrary size, and I’m also interested in the physical process of making it happen.

That computer science problem has been on my list for a long time, but finally I realized that I shouldn’t block the whole project on getting around to writing that code. It took a lot of searching, but I finally found a good, free online tool: Wolfie’s Puzzle Generator.

The next step was to pick a picture. A good picture has a lot of visual interest so you don’t have huge areas of “blue sky” pieces. I wanted to make this as a Christmas gift for Mom so I also wanted something that meant something to her. I settled on a picture of the Seattle waterfront that I’m pretty sure I took while they were out here visiting. I cropped it down to get rid of most of the boring blue sky.

I printed off a 16×20 version of that at Costco and then used 3M spray adhesive to attach it to a thick art board from the craft store. By the way, at 240dpi, this image was almost exactly 20″ wide with no scaling. The picture looks gorgeously sharp. It’s incredible how good modern digital cameras are!

Then it was off to the laser cutter. I spent a long time messing around with various tapes trying to find one that would help protect the surface from burning but also would peel off easily after being cut. I never succeeded. Maybe my adhesive wasn’t strong enough, but for some reason the tape would always pull off with the picture instead of leaving the picture stuck to the art board.

I settled on doing three light passes to slowly cut through with minimal burning. You can still see some burning around the cuts but the picture hides a lot of it. I wanted to make a 1000 piece puzzle but I only squeezed 260 in there due to the dimensions of the pictures and not wanting to make microscopic puzzle pieces. These were 0.75″ square so they were already pretty small.

I don’t expect this puzzle to hold up to a lot of beating but hopefully it will at least work once! If you want to see a video about this, David Picciuto has a making a laser cutter puzzle.

Laser Cutter Marquetry Butterfly

Search for “marquetry” images and you’ll be blown away at the art form of combining small pieces of wood to make amazing pictures. I’ve been intrigued by this, but I’m a nerd so I did it on a laser cutter. I thought it would be way easier and it probably was…. but it was still a challenge.

A while back, David Picciuto from Make Something sent me a box of small wood scraps. There were a lot of very interesting species in there, but they were so tiny it was hard to think of something to do with them. (Kinda makes sense why he would give it away, huh?) Then I hit upon the marquetry idea.

A butterfly seemed like a good first attempt so I found an image online that was close to what I had in my head and then tweaked it and made it into a laser cutter file. I spent many hours tweaking my design with test cuts at the laser cutter to get it as intricate as possible without making pieces so small that the kerf of the laser would totally obliterate the tiny piece.

In the end, I combined coconut palm, walnut, maple, purple heart and a couple other woods that I don’t know the names of to make the butterfly you see below. It’s pretty fragile, especially the antennae, but it at least held together long enough to take a photo. The dark outer wood is the coconut palm. In addition to the top border that you see, I also cut a solid bottom piece that everything glues on to.

This one is a Christmas gift for Mom. Merry Christmas!

Wood Sign

Router-carved signs are a common sight at fairs or even in pop up shops at the mall. I’ve been watching a bunch of Dave Rhoten’s videos on YouTube and finally I decided it was time to try it for myself. I purchased a Dewalt DWP611 along with two special router bits and a nice base plate from Dave’s store.

I bought 1×8 select pine from Home Depot (mostly knot free) and put on a couple coats of shellac. Then I used the laser cutter at work to draw the letters that I wanted to cut. That made the layout portion of the project very easy!

The next step was the most time consuming. I used a very narrow V-bit to carefully cut around the outside of every letter. Then I put in a bigger 90 degree V-bit to draw the big cloud around the outside and cut out everything between the cloud edge and the edge of the letters.

After a little cleanup with some chisels to remove any remaining high spots, I covered the whole piece in black spray paint. When it was dry, I sanded the top which removed the paint from the letters and the part outside the cloud leaving the indented part black. The shellac coating helped to keep the paint from bleeding too deep into the wood on the parts where I didn’t want it to stick.

Finally I used my keyhole bit to cut a slot in the back for a screw or nail so it could be easily hung on the wall.

This was a gift for Don’s brother and his wife in Montana as a thank you for letting us stay with them. And since I was making one, I decided to make two and give one to Don as well. It’s a fun and relatively quick project, but it takes patience!