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Comment Re:What about a bus? (Score 1) 280

If you are up for it, search for information related to the Google self-driving car project. The data I saw was part of a presentation by one of their engineers at an IEEE RAS (Robotics and Automation Society) meeting that showed that in most cities, self-driving taxis would be a big efficiency win over buses, entirely because of low off-peak load factor.

I didn't make it up, but I don't have a link.

Comment Show me the math on the Tesla. (Score 4, Insightful) 280

Show me the math for both ICE cars and Tesla, from well-head to road. Because generating electricity takes energy, and there are losses in the distribution system, and the charging systems are not 100% efficient either. Of course, getting oil out of the ground, refining it into gasoline, and moving the gasoline to refueling stations takes energy, too. Show me the end-to-end math, and then let's talk. A 4:1 advantage for the Tesla seems optimistic to me.

I have the same gripe with calling Teslas "zero emission vehicles". They are not. They are "displaced emission vehicles". Of course, it is easier to control pollution at a single point, and pollution controls scale up quite well, so the overall emissions are less for a Tesla versus an ICE vehicle. But don't claim the emissions are zero, they are just someplace else. (And I will grant that there are benefits to simply displacing emissions -- the Los Angeles valley, for instance, is a bowl, and so pollution tends to hang around in the air for a long time certain months of the year. Displacing the emissions outside the bowl has it's own benefits.)

Comment Re:What about a bus? (Score 0) 280

Actually, buses are terrible. They only run fully occupied during peak times, and transit companies don't pull the big buses and replace them with minivans during off-peak hours. So most bus miles are run with very light loads. On average, buses are far worse than cars for energy efficiency because of the low average load factor.

Comment Re:let it grow organically (Score 1) 167

Thanks for making my case about having the expert first before bringing in the tool. I've done a little bit of carbon fiber, but did not know about epoxy allergy.

Up above in another comment, I read someone saying you need to ventilate laser cutters do work with ABS -- no, you need to *ban* ABS because it destroys the tool. Plastics containing chlorine release chlorine gas when cut, and it doesn't take much ventilation to make it safe for humans. But, the chlorine gas combines with moisture in the air to create HCl, which condenses on all the expensive optic components and strips the coatings off. Soon, laser cutter is junk. Not many people realize that.

A good maker space will make sure there is an expert on each tool that understands how to use it safely and how to maintain the tool in good condition. At one maker space where I am a member, you don't get to use the tool until you have taken a class on the tool that basically teaches you how not to hurt yourself, and how not to hurt the tool.

Comment let it grow organically (Score 2) 167

I've been involved in a couple of maker spaces. One with a lot of machine tools and heavier machines. I've also toured a couple of hot metal oriented shops. My observation is that you really need to let the community guide the build-out and growth. Several reasons: 1. It's hard to predict what people will want until people start using it. 2. You need to have teachers for every tool. 3. Insurance issues will constrain some of your dreams. 4. You want things that people will actually use, because space for tools is a finite resource. 5. Your community may have different tolerance for tool learning curve.

You will find once you start that people will say: "Let's bring in an X." You should ask: Have you used one? Are you expert enough to teach others to use it? If not, can you find someone who is expert enough to teach it? Then after you have a potential teacher, you need to understand from that person the particulars of that machine and whether or not it is a good fit for your community.

Changing topics, here are some things I have seen at different shops, not all in the same shop:
CNC mill, CNC plasma cutter, small injection molding machine (these are all high-learning-curve machines requiring specialist insructors).
manual knee mill, metal lathe, wood lathe.
CNC router.
Sheet metal brakes/punches/english wheel -- surprisingly easy tools to get working with that enable very interesting projects.
Vacuum forming -- simple and versatile.
Hot metal casting -- simple, but needs specialist instructor and special spaces.
Industrial sewing machines and surgers -- enables really cool projects with heavy materials that would kill a home sewing machine.
vinyl cutter.
fiberglass/carbon fiber work set up.
powder coating, paint shop.
glass melting and glass blowing furnaces.
electronics shop for working with surface mount components.
screen printing.
wire welding, mig and tig welding.
I'm sure I'm forgetting some.

Finally: One of my favorite machines is the popcorn machine. I learn a huge amount just by hanging around in the lounge and asking people what they are working on and how they are solving their fabrication problems. You want to build in some space that facilitates interaction.

Comment Look at Olin's curriculum. (Score 1) 634

Olin teaches engineering in a totally different way from other engineering schools. Design projects start in the first semester of the freshman year, and by the time you have graduated you have been in at least 10 project teams. Also, design isn't framed as a technical problem with a technical solution. It is framed as a problem for people with a solution that must work for people. The technical part is just a couple of stages in the middle. They have design classes co-taught by engineering profs and anthropologists for that reason.

Women drop out of engineering because they don't see it as meaningful, and have less tolerance for the bullshit of the two year calculus/physics death march before anything remotely meaningful happens. The traditional engineering curriculum does a poor job of answering the questions: "Why am I here? What is the point?" If you don't bring in your own answer before you start, and one that is powerful enough to sustain you through the bullshit, you will not find an answer in your coursework.

Comment Re:Tools for modifying open hardware designs (Score 3, Interesting) 78

Sorry to tell you, but you and I are about the only two people in the world to believe this. I use gEDA, BTW, which is another free-as-in-speech alternative to KiCAD, and much older. So far, I have been very frustrated trying to make the case that open hardware designs need to be "elephants all the way down" -- FOSS from the hardware design, to the DA tools (and file formats and libraries), to the OS. In fact, I once had a several-post-long exchange with Limor Fried over at AdaFruit's forums where she finally closed off the thread with: "Tools don't matter." I think her opinion is outrageously misguided and short-sighted, but that is an example of what the leaders of the Open Hardware community are thinking. SparkFun must feel the same way, because all of their designs are released on cripple-ware tools, too.

I think we need an open hardware license that includes a clause about openly documented file formats at the very least, and I would push for a license that calls for design files released on open source DA tools. Imagine where the Linux ecosystem would be today without gcc. Gcc isn't a great compiler, but it is open source, and it got us where we are today.

Comment Re:50 Mhz lower limit? Ouch. (Score 1) 135

Ummmm I'm not so sure you can say most hams are HF focused. I think there are a lot more technician class shack-on-a-belt types than hard core HF types. Although, the shack-on-a-belt ham isn't likely to be an experimenter. Then again, the CW-or-die HF crowd isn't really doing bleeding edge experiments either. It seems to me that 50-1000 MHz scores a bulls-eye on most true experimenters.

In any case, there already a zillion options in HF SDR's -- how many are you running now? Personally, I'm annoyed that it doesn't go up to 1.2GHz, that's where I want some hardware to play with.

Comment Values, life-long love of learning (Score 1) 698

My own father passed when I was six years old. Still, his memory was a huge influence on my life. Through my mother, older siblings, and business associates of his, I was constantly reminded of his values. He was known as an honest man of high integrity. I wanted (still want) to be known the same way. That has always been a tall order to live up to. But I am better for it.

He also expected me to learn something every day. I still remember coming home from kindergarden and being asked "What did you learn today?" -- if I said "nothing" or "not much", I was told that wasting a day like that was unacceptable. He expected a specfic, concrete answer to that question each and every day. He belived in education and served on the school board. He encouraged all of his children to pursue higher education in what ever area they were passionate about.

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