I’ve just finished the second version of my electric spinning wheel. My previous versions have more explanation of how electric spinning wheels work see here and here. I decided to use the original name of Electric Eel Wheel 2. (sarcasm)I really like this new idea I came up with of adding a “2” for the second version of a product. Good thing I open source my ideas, perhaps other products will start copying me on this great idea. (/sarcasm)
There a lot of improvements in the new version. Here’s a list:
Much high quality of motor with longer life
Lots of changes to greatly reduce noise (quiet running motor, nylon flanges, …)
Motor controller runs at lower temperatures
No soldering required so the kits easier to assemble
Custom enclosure to protect the electronics and create a more professional appearance
I’ve designed a better electric spinning wheel that is cheaper to make and include detailed build instructions. I also sell kits for this new version. Here is that project’s homepage.
This article is dedicated to Emily. Without her love of spinning and knitting wool I wouldn’t have had willing test subject for my wacky spinning wheel contraptions.
Intro to Basic Spinning Wheel Mechanics
All spinning wheels have a bobbin and a flyer. The bobbin holds the spun yarn and the flyer is what twists the yarn onto the bobbin. The big drive wheel on non-electric spinning wheels is just there to help spin the flyer faster. The electric spinning wheel is much smaller because a small electric motor spins fast enough to eliminate the need for the big drive wheel.
There are a wide variety of spinning wheels. The one I choose to make is the Scotch Tension design. This version uses a brake on the bobbin to control how fast the uptake of the yarn happens. The uptake of the yarn is how fast it is put onto the bobbin. A slower uptake means the yarn will have more twists per foot. Different types of yarn require different amounts of twisting.
The main advantage to an electric spinning wheel is that it can be made smaller and is thus more portable. Another advantage is that getting a good well balanced mechanical spinning wheel can be tricky and an unbalanced wheel isn’t as easy or fast to use. I’ve found that electrical ones can be built for between $50 and $150. Mass produced electrical spinning wheels cost $2000 and cheap looking pvc ebay models sell for $300-$500. I really feel this market is being exploited and it would be awesome if this article starts a little more competition.
Like most engineering problems it took me a few iterations to get everything working well. Below are the five versions it took me to get everything working well.
This version was never completed. It never spun any wool, but it helped me understand the workings of the bobbin and flyer.
The second iteration worked well and it cost me around $50. It used a cheap surplus AC motor. The big problem was that this version was it was constant speed and Emily wanted it to go a little faster. I tried adding a resistor based dimmer switch to my system to control speed of the motor. The dimmer switch’s packaging specifically said not to use it with motors. While I thought I knew better, but it turned out that I didn’t. I seemed like it was going to work, but after a little while the switch released it’s magic smoke molecules. If you don’t need variable speed I’d suggest getting an AC motor like this. At $10 this motor is a steal. You can use a standard lighting switch to turn it on and off. I also wired in a switch to reverse the motor which can be useful since you spin yarn in one direction and then ply strands of yarn together in the other direction.
This version changed to an AC sewing machine motor so that we’d have variable speed and I made a nice box to make it more portable. I used this $35 sewing machine motor. The problem is that the AC motor did not have enough torque at lower speeds. I knew that AC motors didn’t have as much torque as DC motors at slow speeds, but thought that it would be good enough. I was wrong. I’m sure some a bigger AC motor would work, but this one did not cut it. At high speeds it worked fine because there was more torque, but high speeds were too fast for an mortal spinner’s hands. It was amusing watching Emily try and keep up with the high speeds
Version four used this dc motor, power supply, and motor controller. I had avoided DC because it’s more expensive, but it’s still only around $100 with these parts and I’m sure with some searching cheaper parts could be found. One issue I had to solve is that the motor controller by default pulsed at 260 hz which gave caused an annoying hum. I increased the pulse frequency on the motor controller so it was outside the human hearing range by replacing the 470K ohm R5 resistor with a 47K ohm resistor. In theory this reduced the efficiency of the motor, but it still seemed to have enough power for my needs. This version worked fine for a few minutes and then the magic smoke molecules were released. I never liked this motor controller so my next version needed to buff up the motor controller.
I kept the box the same as my last version. All I did was change to using the SyRen 10A motor controller and put this battery in parallel with the power supply. The reason I put the battery in parallel is to protect and sink the energy from the SyRen regenerative motor driver. Here is a good tutorial with a little more info about this. An added benefit of the battery is you can use the spinning wheel for an hour or two in remote locations. This has turned out to be very useful for Emily. I’ve been extremely happy with the SyRen motor controller and if I ever need a high quality motor controller in the future I’ll certainly consider using this or one of the other SyRen controllers.
The best news is that this version of the electronic spinning wheel works great! Here is a video of Emily using it.
Electric Spinning Wheel Design
The motor and electronics I used are linked above. I used these pulleys (smaller, bigger) from McMaster. I also order these aluminum pipes (smaller, bigger). The rest is just wood, bolts, washers, a spacer, an elastic strap, glue, and 6 inches of 1/8×3/4″ aluminum bar. I got all this stuff from Home Depot. I estimate the total cost to be around $150 and this would be less if you built more than one since there is a lot of extra material left after the build. I’m also sure I could find cheaper versions of many of the parts if I did more searching.
Here is a diagram of the my electric spinning wheel.
The bobbin can freely spin on the flyer. If there was no brake on the bobbin then it would spin at the same speed as the flyer and the yarn would get very twisty, but it would never get put onto the bobbin. The scotch tension brake causes the bobin to spin more slowly than the flyer allowing some twist to the yarn and some uptake. Uptake is the term of the yarn getting pulled onto the bobbin. If you applied a full break so the bobin never spun then there would only be uptake and the yarn would have no twists which would also not work. Spinners know that they need to adjust the Stotch tension brake to get a good mix of uptake and twist. The less twists in the yarn the fluffier it is. Knitters will want different amounts of twists in their yarn depending on what they are knitting.
Here is a diagram and picture the explains my flyer/bobbin design.
That should do it. If you have any questions let me know in the comments secontion and I’ll try to answer them.
I’ve made some improvements by adding nylon bushings, a box to hold the electronics, and a redesign of the frame. Here are some pictures.
The last picture shows how I added some straps to the frame. This makes the electric spinning wheel extremely easy to move. This has been a big plus with spinners who often what to move it around.
Here is a video showing how to use the spinning wheel.
Here is a video showing how to setup and adjust the spinning wheel.
New part list:
There are nylon bushings that I got from home depot. These are embedded into the box to help reduce noise. They are 3/8 inch long, have in inner diameter of 1/2 and an outer diameter of 1 inch. The important part here is the inner diameter and the other 2 dimensions could change if needed. I had to cut out a notch so the pipe that holds the bobbin could slide into these.
The bobbins are no longer made using aluminum pipe. They use 2 short pieces of this nylon tubing as spacers. You need to run a 1/2 inch drill threw these spacers a few times so they spin freely on the 1/2 aluminum pipe. Then these spacers are glued into this larger nylon tubing. Then just like before you put some wooden circles onto the bobbin and your done.
“I have not failed. I’ve just found 10,000 ways that won’t work.” ~Thomas Edison
At my real-pay-me-to-solve-problems job, failure happens from time to time. As an engineer it’s important to recognize when a problem can’t be solved in a reasonable manor. Obviously the more important the problem, the higher the criteria for “reasonable”. It’s not surprising to me that some of my hobby projects don’t work out. Heck, it would be boring if everything just worked. I’ve decided to share this learning experience with others.
The goal of this project was to design a card shuffling machine. The topic came up when a friend informed me that there are two categories of shuffling devices on the market. The cheap $20 plastic shufflers you can find at Target, and the $1500+ professional solutions. Both systems are fairly controlled systems, and I thought it would be more interesting to take a Rube Goldberg approach. My card shuffling machine used physical environmental factors (ie air flow) to randomize the cards. In a nutshell my idea was to use a big fan to blow a deck of cards around in a box similar to how those bingo or Powerball lottery machines work. Then after the cards had been randomized I’d have a series of shoots, doors and sensors to get all the cards face down in a nice stack.
I made a prototype of what I thought would work. Here is a video describing how it works.
To get things working reliably I’d need to do a few more iterations of the slides and figure out how to make a small, powerful and cheap fan. I have ideas on how to get around all my known problems, but I believe solving all the problems could turn into a much bigger effort than I had expected when I started this project. Basically I’ve decided I’m not interested enough in this problem to work through these problems I’ve found.
I have a lot of other things I’d like to work on so instead of focusing on this project, I’ve decided to cut my losses and move on to other things. If anybody else decides to pick up this project and improves on it let me know. I’d love to hear about any related past or future projects. I was surprised that my google searches didn’t turn up any projects like this.
I just found this open source project at processing.org that looks supper useful. A lot of people use it to design cross platform GUIs for interfacing the Arduino with the PC since it has easy to use serial communications. Another part that looks useful to me is that it has imaging/camera libraries that should make some of my ideas that require motion tracking and other video related ideas much easier to implement.
I will likely use this in future projects, but for now I just wanted to write it down so I don’t forget about it.