Category Archives: Projects

Lazers

Hi all

An idea popped into my head on the way to work this morning. I have seen websites where people have pulled the lasers out of DVD writers and used them for all manner of fun things. Apparently the lasers from 16x DVD writers are powerfully enough to ignite a match or pop a balloon. Now the thought that occurred to me, was that this laser might be able to cut or tech some substances, although rather slowly. Maybe putting a few of them together pointing at the same spot would give better results. According to one site that I read, the laser from a DVD writer was around 60mW, though Wikipedia indicates that these can be as high as 250mW.

Now a DVD writer can be bought for around R150 ex vat, ex mark up. Now if the output of these lasers is 60mW, then 17 of them would be 1.02W at a cost of R2550 ex vat (R2907 inc vat). This is all excluding the necessary driver circuit though. Of course aligning 17 lasers onto the same spot would take quite some work.

As a cost comparison, I found a 1W semiconductor laser that is usable for burning, cutting etc for $499.95(http://www.amazing1.com/burning-lasers.htm). That’s around R5164.50 at the current exchange rate, excluding shipping, customs and the driver circuit.

So the question is, is it worth it to cannibalize DVD writers for lasers. I’m not sure, but I’m willing to destroy a few to find out.

Warning!!!!
If anyone is interested in playing with lasers, please be careful. Any laser that produces more than 1mW of output power is able to cause damage to your eyes. Please use proper eye protection when using lasers and NEVER look directly into the beam. Just because you have 2 eyes, doesn’t mean that you have a spare.

Electro-etching 1 : SB 0

Ok, so we decided to try some electrolytic etching and machining today. Here is the order of events so far.

  • Find images to etch
  • create some new images
  • combine images into one for easy printing
  • cut glossy pages out of an unneeded magazine
  • print out graphics
  • realize that you forgot to invert the graphics
  • invert and re-print the pictures
  • clean the brass plates with souring pad and methylated spirits
  • tape the graphics to the brass, printed side down
  • iron the lot, hoping that the toner from the print will melt and stick to the brass.
  • take the tape off… carefully
  • soak in hot water to loosen the paper
  • carefully scrub remnants of paper off with fingers and a sponge
  • re-touch bits that didnt stick with a pertinent marker
  • spray the back of the plates with spray paint to insulate them
  • fill a large container with hot water
  • hook a piece of scrap metal mesh on one side of the container as an electrode
  • find a nice big power supply
  • find a plug for the power supply and fit it to the cable
  • attach brass plate to side of container and wire it to the power supply
  • wire the mesh to the other power supply terminal
  • turn on power
  • notice not much happening
  • add salt to water and watch the current flow. lots of bubbles
  • notice lots of green gunk on the water surface
  • eventualy get board and remove plate
  • notice that all thats happened is that toner and the spray paint have flaked off the plate
  • realise that the power terminals are the wrong way around(arrrg)
  • connect second plate the right way around
  • watch more bubbles and gunk
  • notice 3 different colour bands in the solution
  • notice that the current is dropping
  • decide to replace solution
  • notice that something has happened to the plate but not enough
  • mupwI’ decides to use the method to cut through a much bigger metal plate
  • all goes well. lots of bubbles
  • mupwI’ decides that it needs to go faster and adds more salt
  • current rises to around 15 Amps
  • fuse in the power supply calls it quits
  • SB gets board, washes his hands and types everything up in his blog ;-)

oh well, so that’s been my Saturday so far. I’m feeling exhausted now, though it was a fun experiment. I’ll do some more research and try again another day. The weather service says that the its gonna be nice and warm again tomorrow so I think I’ll head to the beach for a bit.

cya

SB

Weekend Projects

Ok, so I haven’t posted in a while. So sue me. I’ve been really busy with work and Ductape and just trying to survive life in general. Anyway, since my friends all seem to be busy or broke or just uninterested in me, I need to find other things to keep my mind occupied. Since IT is my job, I often don’t want to look at a PC on the weekends and I need to find something else to do, so here are my ideas for this weekend.

Electrolytic etching/machining
Making custom T-Shirts
Drawdio

I will try to take lots of pics and post info over the weekend or next week. I’m hoping to show and explain the etching stuff at Ductape next Tuesday. I know I have the etching stuff at home, all ready to go. I just need to grab myself a few cheep t-shirts after work. The Drawdio I spotted on LadyAda’s blog yesterday. Not sure if I have the parts at home for that. I might have to make a trip to A1 Radio tomorrow morning.

If all else fails, I really need some sleep. Caffeine might keep you awake but its no good for your body. Trust me, I know. Maybe if the sun sticks around, I’ll head to the beach for a bit.

cya

SB

Hacker Spaces

Ever since I first heard of hacker spaces, I’ve been enthralled by the idea of a place where like minded people can come together to learn, teach and build things. We are or course talking about the true definition of hacking. The meaning that goes back to before computers were even thought about. Hackers are those who like to learn how things work. They take things apart, and put them back together and make them do new things that they were never meant to do. Hackers thirst for knowledge and crave challenges that stretch their minds.

I first heard about hacker spaces while listening to recorded talks from one of the HOPE conferences(Hackers On Planet Earth). These are basically places where hackers can get together to share information and work on projects. Lets face it, not everyone has the space or tools at home to work on some kinds of projects and no one is an expert in every field. This is where the hacker space really helps its members. It can be a shared workspace with tools that all of its member can use to work on their projects. With enough members, there will most likely be someone knowledgeable around that you can ask for help or who can teach you to use a particular tool.

Over the past few years a number of hacker spaces have popped up all over the world. At the Last Hope conference, a website dedicated to hacker spaces was advertised, http://www.hackerspaces.org/ This site aims to help people find hacker spaces in their area, to help people to start spaces where there are none and to enable hacker spaces to communicate amongst themselves to share ideas as to what works and what doesn’t as far as running the space is concerned. I took a look at the site and wasn’t exactly surprised to find that there were no spaces listed in Africa. If I wasn’t motivated to start a space before, I am now.

Personally, my interests are generally in the region of computers, electronics and radio, though my interests cover a wide range of technologies and engineering. I would like to have a hacker space in the Durban area where one can come to work with others on cool electronic and computer based projects but also to be able to build a desk or fabricate a computer case from scratch or build a boat if they so wish. Obviously what is possible depends on space and tools available, and ones imagination. Many hands make light work too so involving others helps you get your project done quicker and you may get valuable input and ideas that you would never have thought of before. Of course when others have projects you can lend a had, ideas etc and everyone benefits from the pool of knowledge.

Ok, so here is where I ask for input from you. Would you like to participate in a Hacker Space in the Durban area? What sort of group projects would you like to see achieved? What sort of facilities would you like to see available for members to use? Would you or someone you know be interested in donating tools, materials or cash toward setting up such a space? How much would you be wiling to spend on a monthly basis toward keeping such a space going? Keep in mind guys, rent has to be paid by someone and in this case its the members. Any other ideas are most welcome.

I’ll leave you now with a few links to info on hacker spaces so you can get an idea of what its about.

Happy hacking ;-)

SB

NYC Resistor
HACDC
the hacktory
NoiseBridge

Building Hacker Spaces – talk from The Fifth Hope
Building a Hacker Space – talk from Hope Number Six
Building Hacker Spaces Everywhere – Your Excuses are Invalid – talk from The Last Hope