More on Blowguns

A while back, I wrote a post about making and shooting a homemade blowgun. Shooting blowguns is becoming quite a popular sport - both in the United States as well as in Japan. And it's inexpensive and thus affordable by nearly anybody. It's also one of the safest of the shooting sports if one uses some common sense.

My previous blowgun post may be found here:

http://inkarlslab.blogspot.com/2011/10/pvc-blowgun.html

Recently, I have found some other web sites on blowgunning that I think are well worthwhile to check out. A couple general interest ones are here:

This one is a great discussion group that covers all aspects of making and using blowguns.
http://blowgunforum.com

The guy who did this site has an engineering background, and offers some interesting analysis as well as some construction ideas of his own.
http://www.polar-electric.com/Blowgun/Darts/index.html#TableTop

Here is an organization devoted to furthering blowgun shooting as a sport.
http://usblowgun.com/

Measuring Performance
Anyone seriously pursuing the shooting sports will at some point want to measure the velocity of their projectiles. Velocity has a direct impact (no pun intended) on both accuracy as well as, in the case of hunting, how effective it is at killing the intended game. Relating to blowguns, velocity measurements also give a quantitative measure of how one's lung power is developing over time.

Regular readers of this blog have also seen my "Poor Man's Ballistic Chronometer" plans. This definitely follows the old adage that "necessity is the notherhood of invention." I did not have the money in the family budget to buy a ballastic chronometer for measuring dart and arrow velocities, so I did some research and built my own out of about $15 in electronic parts. The article, done in two posts, starts here:

http://inkarlslab.blogspot.com/2012/01/poor-mans-ballistic-chronometer-part-1.html

The engineer I mentioned above had a somewhat similar idea, though he did things a bit differently. He has written some cool looking software that is free for downloading. Looks like a viable idea, though I doubt it would work well outdoors or in environments with a lot of background noise. Here's his setup:
http://www.polar-electric.com/Blowgun/Software/Dartspeed.html



A Word of Caution:

This should be common sense, but in view of how rare a commodity it is in this world today, the following bears mentioning:

NEVER aim a blowgun at, or shoot at, another person or any animal you don't intend to kill and eat!
There have been some news stories about people who have shot at ducks and geese in municipal parks with blowguns, resulting in darts still being lodged in their bodies. Do NOT do a stupid stunt like that! This gives ALL of us who engage in blowgunning as a sport a bad name and could result in blowguns being made illegal EVERYWHERE - as they already have in Kalifornia and Massachusetts.

If you want to hunt small game with a blowgun, as some folks successfully do, make sure you have the right type of equipment and comply with all local laws!

Children and teenagers should be well supervised when using this or any other weapon.


Sport blowgun shooting can be a fun and safe activity for people of all ages and from all walks of life. Blowguns, darts, or the makings for doing your own, are available just about anywhere and are quite inexpensive. I did mine and the darts for about $10 worth of supplies found at the hardware store and/or around the house.

An Experimenter's Site Worth Checking Out

Occasionally, I find a truly unique website posted by a fellow experimenter. This one, by Nyle Steiner K7NS, http://www.sparkbangbuzz.com/index.html definitely fits that description. Indeed, it shoes that remarkable things can be done WITHOUT modern devices. Some of his stuff definitely has a sort of Jules Verne-esque "steampunk" feel. VERY COOL!

This site features homemade vaccuum tubes, homemade semiconductor devices, several schemes for broadcasting speech and music over a light beam, and more.

Some of the technologies featured date back to the early 1900s, but are doable by the amateur scientist today.

Fascinating stuff!! My only caveat is if you decide to replicate Mr Steiner's experiments in which small pieces of galvanized metal are heated, I'd suggest doing this OUTDOORS with a small fan to blow the fumes away from you - said fumes are highly toxic.

As always - Have fun and stay safe!

Water Everywhere, But Nary a Drop To Drink

In a recent post I mentioned how potable water is becoming a scarce commodity. Indeed, only about 3% of all the world's water is drinkable - the rest is seawater. Of that drinkable 3%, a substantial amount is in a huge lake in Siberia. In much of the developing world, there is still a huge burden of disease and mortality due to drinking contaminated water. Diseases such as typhoid and cholera still plague the Third World. The World Health Organization estimates there are 3- 5 million cholera cases world wide and that of these, 100,000+ will die. This is cholera alone; typhoid, river blindness, and other diseases compound these numbers.

Here in the United States, we do enjoy drinking water standards that are the envy of much of the world. That said, that does NOT mean that all is well here. It isn't. Any google search of "tap water contamination", or anything along those lines, will turn up a plethora of articles about the heavy metal contaminants, the harmful microorganisms, and even prescription drugs in measurable quantities in municiple water supplies. Fluoride, which is routinely added to municipal water supplies here in America, was used in the drinking water in Nazi prison camps to make the prisoners easier to manage. The Nazi doctors knew well that fluoride lowers IQ and brain functioning, reduces a person's volition, and is basically a poison. Yet we deliberately put this in OUR drinking water???

Even without these issues, water quality is still impacted whenever there is a hurricane, or a water main breaks in a city, etc. Annually, there are tens of thousands of water main breaks in America due to infrastructure that was outdated 80 years ago. This not only causes water outages for millions of people, but it also provides opportunities for pathogens to enter their water supply during the break and repair process. During the Katrina disaster in New Orleans, there was oil and gasoline from cars, sewage, and many other pollutants introduced into the municipal water supply due to the flooding. This is normal during such flooding events, and such conditions may last for weeks - even after service is restored.

As part of my college studies, I have made simple, cheap, but effective water purification one of my areas of personal research. The most popular methods are:

1) Boiling or distillation - while these are effective, they use LOTS of fuel. In many Third-world countries, and in post-disaster scenarios, fuel for cooking or boiling water is a scarce resource.
2) Chemicals - Chlorine Bleach or Halizone are well known by outdoorsmen and others, but these impart a bad taste to water, don't last long in storage, and are not always available. Chlorine can also combine with other chemicals in water to produce carcinogenic (cancer-causing) compounds. Also, something - such as activated charcoal - still has to be done to remove chemical pollutants.
3) Micro-pore filtration - works well. Basically this uses a ceramic fliter element that can filter stuff to less than a micron, which keeps out most microorganisms. These filters are expensive, can clog, and also generally aren't available during emergencies and in Third World countries. Also, something - such as activated charcoal - still has to be done to remove chemical pollutants.
4) Carbon filters - or "activated charcoal" - does a great job removing chemical pollutants from water, but another method is needed to remove the microorganisms that cause Giardiasis, cholera, typhoid, etc.

I am personally researching several alternative methods of water purification - some are easily replicated at home by someone with reasonable mechanical skills. These include:

1) Solar water purification - while NOT a filtration system, sunlight can and does kill pathogens if the water is exposed onge enough. Some method of pre-filtering would still be needed to remove particulate matter that could harbor pathogens. The pre-filter could be as simple as several layers of coffee filters. The solar method can be as simple as leaving a plastic water bottle lying in the sun all day. A curved aluminum foil reflector would be placed behind the bottle and used to concentrate the rays so both sides of the bottle are irradiated.
2) Ultraviolet light - UV light in the 260 nm wavelengths is widely used in industry and food processing to kill pathogens. Likewise, it is used successfully to decontaminate water. Similar in concept to the solar purifier, it is generally done with special fluorescent lamps and is more easily controlled and repeatable than the solar method. Also needs a pre-filter as does the solar method.
3) Ozone - an elegant solution, ozone kills pathogens AND neutralizes numerous chemical pollutants. Ozone is a special, highly reactive form of oxygen molecule that has three oxygen atoms, rather than the normal 2 that we breathe in the air. Ozone may be generated via UV emitting fluorescent lamps or by electrical corona discharge through air. A car ignition coil with a simple transistorized oscillator circuit can generate the 20KV or more needed to make a decent corona discharge in an enclosed tube fed with air from an aquarium pump.

It should be pointed out that sources such as rain water or water pulled from lakes and streams should ALWAYS be pre-filtered due to the presence of fine particulates that microbes attach themselves to. Indeed, my own lab tests show that using a simple paper coffee filter to remove these particles causes a substantial reduction in bacteria even before any other methods are employed to decontaminate the water. In exigent situations, a tee-shirt or a bandanna folded multiple times can work too. In a future post I will detail an easy and cheap way to test your water at home for bacterial load, and will go into more specifics on homemade water filters using common household materials.

Meanwhile, here are some links to articles dealing with bad stuff in our tap water:

http://ezinearticles.com/?Dont-Drink-Tap-Water---10-Reasons-Why-Not-to-Drink-Tap-Water&id=2086422

http://danielmiessler.com/blog/more-reason-to-drinking-bottled-water

www.treehugger.com/green-food/epa-looking-at-regulation-of-gender-bender-chemicals-in-drinking-water.html

http://www.prisonplanet.com/fox-news-covers-mass-drugging-of-society-with-lithium.html

Jobs and Natural Resources

As we all know, jobs and natural resources are increasingly scarce in today's world. While this is mainly a tech and DIY related blog, occasionally I will mention issues I think are related to the subjects at hand. Jobs and natural resources are an imperative for nearly all my readership - indeed the two are intertwined.

No doubt anyone buying groceries has noticed the prices of food trending sharply upward within the past couple years, despite government and media claims that inflation "is nearly flat". Food prices are going up for a variety of reasons. These include the following:
1) Fuel costs. Oil is used to make fertilizer, run the farm itself, refrigerate the product, and truck it to market. The typical food we eat has travelled some 1600 miles from its point of origin to our table, according to some sources.
2) Commodities Speculation. Commodities speculators are wreaking havoc with the prices of precious metals, fuel, and food.
3) Fuel alcohol production. Programs designed to create fuel alcohol to supplement existing fossil fuels are diverting resources from food production to fuels. Corn that was used to feed our cows and chickens is now being fermented into alcohol to run vehicles.
4) Devaluation of the Dollar. Due to our government's drunken-sailor style spending spree and Fed Chairman Ben Bernanke's policy of "Quantitative Easing", which is essentially a process of creating money out of thin air with nothing tangible to back it, the value of a dollar has severely eroded. A simple law of supply and demand economics - when you have more dollars chasing the same supply of goods, the buying power of a dollar decreases - and prices go up as a result.
5) Water. Simply put, we're running out of fresh, potable water. 97% of Earth's water is in the oceans and cannot be used directly for drinking or irrigation. And we're in danger of pumping some of our most important ground water aquifers dry.

Per point number 5 above, see the following article:
http://www.pewstates.org/projects/stateline/headlines/in-drought-ravaged-plains-efforts-to-save-a-vital-aquifer-85899460061

Jobs
Without raw materials to make and grow stuff with, we can't have job growth, either. The job situation is far more complicated than that, at this point. America's current employment situation is by far most attributable to lopsided treaties such as GATT and NAFTA which place Americans in direct competition with people earning a fraction of what it costs to live in America. On top of lopsided treaties, we have simple bad management on the part of local and state governments which makes it harder to start or maintain a business. The following article details what some states are trying to do about it:

http://www.pewstates.org/projects/stateline/headlines/how-did-states-create-jobs-85899482158

I invite my readers to do further research into these and realted issues; only by arming one's self with factual information can one NOT be misled by all the disinformation, misinformation, and half-truths being disseminated out there.

Painting PVC Pipe

Just during the past week, someone came to this blog after a google search dealing with "how to paint PVC". This is indeed a good question, so I thought I'd briefly touch on this topic.

Can PVC pipe be painted?
In a word - yes. That said, surface preparation is critical, as it is with painting anything else. There are also some other small but important details to keep in mind when doing this:

1) The surface MUST be clean of all oil, dirt, dampness, etc. or any coating you use won't adhere properly. I typically do this with rubbing alcohol and a clean rag.
2) The surface should be lightly scuffed with steel wool or a very fine grit sandpaper - such as 600 grit or finer. Once you sand or steel wool the pipe, CLEAN it AGAIN with more rubbing alcohol and a clean, lint-free rag.
3) Use a paint designed for PVC. If you don't, you will be disappointed. More on this below.
4) Good spray can technique applies here - use several thin coats rather than one thick one to avoid runs and drips. Also, spray with the can 10" or a foot (30 cm) away from what you are painting. Keep the can moving so you don't build up too much paint on one area. If you haven't done much spray painting, practice on some scrap first before doing your critical work.

Coatings for PVC:

Years ago, I attempted to apply a cammo paint job to an antenna mast I built from PVC pipe for my homemade portable QRP ham rig. I used either Krylon or Rustoleum - I don't remember now. The paint job looked beautiful when freshly done, but proceded to flake off whenever the pipe was bumped. I could scrape the paint off easily with my thumbnail.

Since then, Rustoleum has come out with a primer that works on PVC and some other plastics. Krylon, if I remember right, has come out with a small assortment of colors that work directly on plastics, including PVC - no primer needed. The trouble with the Krylon product is the color selection for their plastic paint is, in my opinion, rather limited.

By using the Rustoleum primer as a basecoat, you can use whatever color you want from their standard line of spray paints. I actually used Krylon's flat "Hunter Green" paint on a 50 caliber blowgun I'm making for a friend. The base coat was Rustoleum primer for PVC. It seems to have worked OK so far. A few accidents here in the lab while handling the pipe don't appear to have caused damage. See the photos for the products used as well as the blowgun.




Caveats:

1) I have not, to date, subjected any of these painted surfaces to severe, real-world testing yet. What I can say is that casual handling and occasional droppage against other objects hasn't apparently caused chipping or scratching. So compared to the antenna mast described earlier this IS a huge improvement.

2) ANY time one applies a solvent-based coating to PVC or other plastics, the base material is weakened somewhat. One should take this into consideration if one decides to use any kind of paint on something like a PVC archery bow that is subject to significant stress during use.


Hope this information helps someone. Have fun and stay safe.