Saturday, October 6, 2012

What's been going on

I see that the last time I made a post was in May, about 6 months ago. In that time, I've been pretty busy and have only been able to do the same hikes I've been doing-the stairs here and there and maybe olomana once in a while.

I've been working on quite a few modification projects since the last post, and I'm having some fun learning about all the details involved in each mod.

I've been studying for the LSAT, or the law school admission test, but I'm realizing as I study more for it that law might not be something I'll enjoy or be comfortable doing. I've been hacking and modifying stuff after the success of the Surefire Kroma Mod, which I use as an everyday carry light now. I'm beginning to realize it may be more fun to be an engineer than a lawyer, and may end up going to mechanical engineering school. I've also been busy with classes, since the classes I'm taking now are mostly major classes that are important to my degree. The classes are actually more fun than I thought they would be, but that's probably because all but one deal with computers and coding.

So what projects have I been busy with since the flashlight? Well, I recently became interested in drinking coffee, so I looked in to Keurig machines. Keurig machines range from about the size of a traditional coffeemaker to larger than a microwave oven. These machines brew a single cup of coffee at a time, and the higher-end models let you tweak the temperature, set auto on and off times, and choose from a larger variety of cup sizes. At work, our boss picked up a Keurig B70 from Costco for the whole office to use, provided that we brought our own coffee. After using the Keurig for a while, I got interested in getting my own machine, but even the cheapest Keurig machine starts at about $100. So I went to eBay to see if there were any cheaper machines. No luck. Then I thought, I've got tools, so let's see if I can buy a broken machine and get it working again. I found a broken Keurig B140 for $30 on eBay and quickly swiped it up. I figured that if I couldn't get it working, I could at least see how the machines work. The Keurig arrived after about 2 weeks, since cheap shipping to Hawaii means long waiting times. I spent about 6 hours unscrewing everything and prying stuff apart. The way Keurig machines work is pretty simple, but the way Keurig engineers put everything together in such a small package is pretty cool.

I did get the B140 running, and I sold it to a friend at work. I didn't really plan on keeping the B140 because it was a low to medium level machine, which meant I didn't have much customization flexibility. It actually only had three cup options-6, 8, and 10 ounces-and the ability to turn on a 2 hour auto off setting. I had become fond of the 4 ounce cup size on the B70, and wanted to try to find a machine around that level so I could have a smaller, more concentrated cup of coffee.

Back to eBay, and after several unsuccessful attempts at getting a B70 (mostly due to shipping to Hawaii), I found a Keurig B150. This machine is the office version of the B70 and has lots more customization options. The regular price is about $200 used or $250 new, and I got my machine for less than a third of the price for a used one. Granted, it was broken, but I found out it was only listed as broken for liability reasons. The machine took just as long as the first to come-about 2 weeks-and I worked on that one for about 6 hours each on 2 days. The problem listed was that it was pouring out smaller cups than the amount selected. When I got it, I plugged it in and ran it, and it poured a full cup. Did I just pay a discount price for a working machine? I found out later that the machine had a problem boiling the water too. It would suck water from the tank but wouldn't start the boiler to heat the water. Looks like I would get to take the machine apart after all.

The B150 is a pretty cool machine. It has 5 cup sizes-4, 6, 8, 10, and 12 ounce cups. It has a programmable temperature range from 188 to 198 degrees Fahrenheit. There is a programmable clock and auto power setting that lets you program when the machine turns on and/or off. There is a 2 hour auto shutoff timer that can be enabled just like the B140. The cool thing about the B150 is that it has a color touch screen for interaction. A little over-the-top, but it's actually pretty convenient. There is also a diagnostic mode that lets you do all kinds of detailed operations, and a 90 ounce water tank tops it all off, being the biggest water tank Keurig makes. It's convenient not to have to fill up the tank as often as with the B70.

One thing I found out about the cup sizes is that the machine will dispense 0.75 ounces less than the stated size-the 4 ounce selection dispenses 3.25 ounces and the 8 ounce selection dispenses 7.25 ounces. This is so that when you have a cup that holds exactly the amount you choose, it won't fill to the rim or overflow. I like this, but some people may not like being shorted 0.75 ounces. If I need more than the largest possible size, which is 12 ounces (11.25 ounces), then I'll just run the machine more than once. It heats so quickly that you don't have to worry about waiting.

In Keurig machines the water is held in the water tank or can be plumbed directly in higher-end office models. The B150 has a boiler, 2 pumps, a logic board, some plastic valves and many feet of silicone tubing running throughout the inside of the machine as well as 2 solenoid valves-I'll get to the valves later; they are pretty much the weak link of the machine. Pretty much all the Keurig machines that have a water tank have the same setup. Most models other than the B150 will have a black and white blue backlit LCD. The water is pumped from the tank or direct line into the boiler and heated to just under boiling in about 5 minutes-pretty fast. The boiler actually holds way more water than just one cup's worth so that when new water is pumped in and cups are being made back-to-back, the machine doesn't need to make you wait for a long time while it heats the water. The Keurig Mini is the only machine that doesn't keep a reserve and requires you to pour water into the machine like a traditional style coffee maker each time you make a cup of coffee. This reserve setup is pretty smart because water has a high specific heat. The downside is that on the home models, you can't empty the boiler reserve water. Office models provide a way to empty the water from the boiler, which is a good reason to get an office model if you can. I think the machines hold about 20-30 ounces of water in reserve, and the water will just sit in the machine if you can't or don't empty it.

Now the solenoids. A solenoid valve uses magnetic field to open or close a valve when a current is passed through it. In Keurig machines, the solenoids are normally closed, which means that when there is no power to the solenoids or to the machine, the solenoids will be closed, and nothing can pass through. The problem with the solenoids used in Keurig machines is that they are intended for automotive use. A reviewer on Amazon found the part number of the solenoid used in Keurig machines and a Google search reveals that the solenoid valve can be purchased mainly from automotive sites. Although one site lists the coffee makers in the possible applications, it also lists power seats and massage chairs, both of which don't deal with liquids. Because of this, many solenoids in Keurig machines leak and rust, which leads to their failure. That is exactly what happened to the B150 I bought, and the failed solenoid was what kept the machine from heating the water. The solenoid seemed to connect a bypass valve that would route any excess pressure into the water tank. I wasn't too sure why, but it seemed that if there was too much pressure in the boiler, it wouldn't heat the water because the solenoid wouldn't allow venting of the hot air produced by the boiling water. When the machine is plugged in, normally the solenoid automatically opens and closes to vent any pressure. When brewing, the solenoid stays in its normally closed position. This is because it needs to create pressure so the water will flow out through the intended output nozzle and not back into the water tank. Disconnecting the solenoid from the logic board fixed the problem, but then I was stuck with what could possibly happen if I left it disconnected, so I went on a search for a new solenoid. I read that the newer Keurigs use a new type of solenoid, and I was lucky enough to find this solenoid that was being sold as a part so I wouldn't have to buy another whole broken machine. After switching the solenoids, the machine functions perfectly. It heats the water quickly and pours the correct amount of water.

Another project since the light was my leatherman key modification. I've taken a Leatherman Squirt and a Leatherman Style CS and modified them into one tool that fits my house keys and some other tools. I'll get a picture of the tool up in a little, and I didn't like how my keys jingled when I walked with them, so I looked into modifying the keys and found out a leatherman tool would work well. There's an Instructable here and a thread here that shows modifications to leathermans that lets you fit keys.

The hardest part of the leatherman mod was finding the old style squirts with allen screws instead of the rivets. eBay is usually my go-to for finding what I'm looking for, and I found a bunch of older squirts that I could use. I wanted the scissors instead of the pliers since I already have a leatherman wave, so I got Squirt S4s. However, leatherman only produced the S4 after they started using rivets, so I needed to get the older P4 and PS4 as well. After I got the leatherman tools in the mail, I took them apart into their many tiny pieces. I needed a tool to reference from when modifying the keys, so I used the nail file, since it was the biggest. I used a dremel to cut the keys and a drill to make the hole. One key took me about 3 hours, so I worked on the keys for more than one day. Then I sanded down the burrs and put everything together. You'll need all kinds of washers depending on the size of your keys and what you're trying to put into your tool. Since I had the other leatherman tools, I used the washers from those. There is one last modification that I'm not even sure will work, but the person who modified their leatherman in the thread link above got a light in his. I was going to try to put a light from my old swiss army knife into the leatherman, but I'm still working out how to do that.

Now with those projects finished, I've moved onto one that's a little bigger. Many people have heard of Kickstarter, where people pledge money to aspiring inventors or businesspeople and can receive rewards if pledges from everyone reach a set goal. The site was created and is run by Amazon, so it's definitely reliable. It uses Amazon's payment system to collect money for pledges, and money will only be collected if a project reaches its goal. I've already pledged money for the Lunatik Touch Pen and received my rewards which were styli with clicky style pens built in. You can see more about the pens here, which work pretty well. They glide nicely across an ipad or iphone screen and are convenient when you want to use the pen too.

A downside to Kickstarter is that although the project creators give projected delivery dates for rewards, you shouldn't count on them meeting those dates. The rewards may still be in the prototype or beta phase, which is the whole reason you are pledging money in the first place-to help the creators see if their products will have potential in the market to succeed and to help them reach production minimums since mass production is expensive. People who pledge money will usually get discounts off the projected retail price or a special version only available on Kickstarter, which may help you decide to pledge money for a project. Creators will post videos showcasing their products, and the videos for good products will usually be well-made.

That was quite a long introduction. Anyway, I was looking around on Kickstarter and came across the Boosted Boards project. These guys at Boosted have a really fun and cool idea-take some high powered brushless motors and put them on a skateboard in order to make a really compact and versatile skateboard. Before the Boosted Boards, all electric skateboards on the market were fast and powerful at the expense of being bulky and very heavy. Most measure in at around 20-30 pounds, but some bigger ones can reach into the 50-60 pound range. The guys at Boosted have got their board down to about 12-15 pounds, which is really good considering they're using a Loaded Vanguard, a board that's already about 8 pounds.

I had always wanted an electric skateboard for the ability to ride up hills and to play around with, but the size, weight and price of electric skateboards made me stick with my trusty Sector 9 board. The Boosted Board is way up there in price, which is keeping me away from it as well, where a Kickstarter pledge of $1200 will get you a production-ready longboard. That price is twice as much as some other electric boards out now, but since the Boosted Board is the only compact electric board out, there's a premium you pay to get one. The board itself is about $300, and after doing quite a bit of research into motors and the like, the parts that make the board move on its own will cost around $400-$500. So where does that extra $500 go? In their video, the Boosted guys explain how the board is a hardware product and that basically the cost, time, and effort they put into the board is reflected in the price of the board. They have put lots of time into designing the drivetrain and layout of the board, which took years. Everything had to be designed in a CAD type software and tested extensively. The high price is understandable and just makes people want it more.

As much as I want to drop $1200 for the cool board, I thought it through and didn't think it was a good thing to blow money on. For that much money, you can pretty much get an old used car, but seeing how the board would become a primary mode of transportation for some, that price seems fair. Also, the savings in gas would help pay for the board. I live pretty far (in terms of Hawaii distances) from college and have to drive at least 10 miles a day, so the Boosted Board range comes up a little short. I could get additional battery packs, and also try to let the board charge at work, but that would add to the cost and bulk. There's also the problem of having to deal with the stuff I would need to carry while riding the board. Instead of weighing the pros and cons any further, I set out to try and make my own electric board. I just need something that can go short distances and can take me up a hill when I need to go to certain classes. The Boosted Board is rated to have a range of 6 miles with a 180 pound rider. The UH Manoa campus is listed as being 320 acres, and in reality, a commute from class to class on the campus is usually less than 1/2 a mile. I'm much lighter than 180 lbs, so if I could match the power on the Boosted Board, I could get some speed and still be able to go a reasonable distance.

I'm still looking into everything, so I'll see how it goes. If everything goes according to plan, I'll put it up here.