Covered Topics

Please see the list of the topics I've covered. It's located near the bottom of the page. Thanks for stopping in!!

Monday, April 26, 2010

Industrial Cleaning with Household Products

I have worked on lots of machines in my lifetime - cars and trucks, motorcycles, small engine powered equipment, HVAC systems, and most recently - machine shop tools. Part of the service usually involves cleanup of oil, grease, dirt, and/or other contamination.

In recent times, it has been increasingly difficult obtaining the solvents needed to get real work done. "Alkabrite(R)", which I'm told is basically an industrial lye solution, is no longer accepted in my area for use on kitchen refrigeration equipment. Many refrigeration houses I've talked to no longer carry it at all. A shame, as it is useful for de-greasing machinery of all types as well as for cleaning refrigeration and HVAC coils. If you work on cars you no doubt are familiar with Berryman's Chem-Dip(R) in the red, white, and blue bucket for carburetor cleaning. This, too, is becoming difficult to buy in many areas due to the restrictions on volatile organic compounds (VOCs).

Especially if you are unfortunate enough to live in the Southern California Air Quality Management District (SCAQMD), you may even find it difficult to purchase the so-called "eco-friendly" stuff. Some suppliers won't sell it to you unless you work for an auto repair shop, and when they do, they charge outrageous prices for the stuff.

Here, for what it's worth, are some workarounds I've found using readily available household products:

Simple Green(R)

Simple Green is relatively non-toxic and, as far as I know, non flammable. Unlike carburetor cleaner it will NOT asphyxiate or poison you with fumes, nor is it caustic to skin like Alkabrite(R) is. In aerosol form it is a lung and respiratory irritant, but used with care I have found it to be relatively safe compared to solvent based cleaners. Here's two unconventional uses I have found for this inexpensive and readily available product:

Air Conditioners Simple Green(R) works great for cleaning air conditioner and refrigeration coils. If the coils are dirty, performance will suffer and the evaporator (indoor) coil may freeze up due to restricted air flow. Filters should be changed at least once a season; the coils should be cleaned annually.
When I used Simple Green(R) commercially on motel window A/C units, I was amazed at how well it removed the several years' build-up of resinous tobacco grime and dirt from them. To do this, use plastic bags and duct tape to protect the motor and any other electrical parts. Fill a plastic spray bottle with a 50/50 mixture of Simple Green(R) and hot water. Spray this mixture on the coil and let it sit for 5-10 minutes. Using a garden hose and trigger-activated spray nozzle, carefully direct a spray of water through the coil from the INSIDE of the unit outward. Work slowly back and forth over the entire coil area. This will lift away much of the dirt and grime; the spray will also physically dislodge any impacted material from between the coil's aluminum fins. If there is still grime in the fins or on the surface, repeat application. Shine a flashlight through the coil from the back side - you should see light clearly through the fins - refracted only by water droplets. Depending on what was previously on them, the fins may be stained or oxidized, but there should be no oil, dirt, or grime left. When you are done, use a compressed air source to blow the excess moisture out of the fins and off of any other parts or assemblies. Do the "flashlight test" again - it should show a nice, clean coil free of any debris or obstruction.

1) This seems obvious, but I'll say it anyway: You need to remove the unit from the window or wall it is installed in BEFORE trying this. I typically used a sidewalk, parking area, or driveway where I had a hard, dirt-free surface on which to work.
2) MAKE SURE all electrical parts are THOROUGHLY DRY before applying power - if you are unsure, or if you know water has leaked past your plastic bags and tape, use compressed air to blow any moisture from them and allow the unit to air-dry for a couple days.
3) I've used this technique on central HVAC systems, too, and it works quite well. You will have to be VERY careful of how much water you use so you don't overflow water out of the evaporator pan and onto your floor. Apply the water spray in short, quick blasts, allowing time for the water to be carried off by the drain. Depending on the design of your particular air handler, you may need a piece of sheet metal or thin plywood behind your coil to redirect spray and splatter back into the evaporator drain pan. Also, you will likely need to remove the squirrel cage blower from the unit to avoid getting water in the motor on these units.
4) Don't forget to do the OUTDOOR coils - as these also need cleaning.
5) Last but NOT LEAST: Be careful with the compressed air source - you can "mash" or collapse the fins if you use too much pressure. This will restrict the air flow when the unit is placed back in service. If you do mash some fins, use a "fin straightener" purchased from an HVAC supply house to GENTLY straighten them. This tool consists of a short handle with several interchangeable plastic "combs". These have teeth of differing thicknesses for different fin spacings. Use the one which most closely aligns with your coil's fins.

A couple years ago, I needed to clean the carburetor on my 20 year old portable generator. While I do have a bucket of Berryman's Chem Dip(R) for doing this sort of thing, I'm saving it for use only in an emergency or on the toughest jobs. Simple green(R) again came to the rescue here. Mix a 50/50 solution of Simple Green(R) and water sufficient to immerse the entire carburetor. Heat this in a metal container (NOT a pan you ever plan to cook food in!) on the stove to about 120 degrees F. This is somewhat hotter than bath water and warm enough to assure fast results, while still safe for most plastic parts. When I did this, all the garbage on both the outside and inside of the carb literally melted away in seconds! It made short work of the grayish colored gook left from gasoline that had sat in the float bowl for a couple years.
Disassemble your carb and soak the parts in the customary manner. I use a kitchen strainer for holding the small parts. I tie a wire to the large parts for dipping them in the hot solution. Periodically agitate the parts; I find that 20-30 minutes in the soak is usually plenty. When you are done, rinse your parts THOROUGHLY in running water. BE SURE to blow all the little tubes, ports, and passages clean with a compressed air source to remove dirt particles and water that could cause trouble later. Those cans of compressed air for blowing dirt out of PC cabinets work GREAT for this - and are a godsend for folks without access to an air compressor! The straw attachment on these cans allows you to direct the air blast right where you need it.

Neat Home-Made Goo for Removing Grease, Cosmoline(R), ...
Recently I helped a friend clean up some imported metal working equipment. This was coated with cosmoline(R) - a thick, toxic substance that often dries semi-hard and can be difficult to remove. Normally one would use some toxic cleaner bought from a hardware or auto parts store. Not wanting to use messy, toxic, and expensive chemicals - he came up with this substitute that's cheap, non-toxic, and actually works. With his kind permission, I have posted the recipe here:

Mix 2 - 3 parts lard (you buy it in a plastic tub at the grocery store) to 1 part vegetable oil. Use a fork and mash the ingredients together in a dish until you get a greasy paste that's roughly the thickness and appearance of phlegm. Adjust the ratio of lard to oil slightly as needed to get the desired consistency. Wearing rubber gloves, rub this mixture onto the surface that needs cleaning. Allow the mixture to sit. For something stubborn like cosmoline(R), you will want to allow an hour or more. Use a plastic spoon, plastic ice scraper, or the like to scrape off the worst of the mess. Use paper towels, followed up by a terry cloth shop rag, to rub the surface as clean as possible. If needed, re-apply the goop and let sit another 1/2 hour. Scrape off and wipe down as before. When you are done with this, you can either wash the surface with soap and water, then dry - or else simply wipe it clean with a fresh shop rag.

Bare metal surfaces should then be wiped with a light coat of machine oil to protect them from rust. Motor oil is okay in a pinch, too.

CAUTION: Remember that oily rags or paper towels can spontaneously combust under the right conditions - so dispose of these safely in a metal container.

Monday, April 12, 2010

Some Thoughts on Planting Your Own Garden

With the arrival of Springtime, one's attention often turns to gardening. Indeed, there are few pleasures more sublime than the taste of home-grown vegetables. My thought is that many folks who "don't like vegetables" simply have only tasted the anemic stuff at the grocery store. I have grown vegetables and kitchen herbs in containers for the past decade. Here are a few quick thoughts, based upon my experience:

1) Containers - use buckets, pots, or other containers that are lightly colored, or else paint them. Light colors such as white, beige, tan, or even the "terra cotta" clay flower pot color are OK. The reason to use these is that dark colored containers will absorb more of the sun's heat and could cook the roots of your plants! I learned this one the hard way when I tried to save money and use the cheap, dark gray pots they dispose of at the nursery!

I've used 18-gallon plastic storage bins with excellent results - but try to go for light colored ones! The lid doubles as a "coaster" to set the bin on; during the winter the lid can be put back on the bin. Drill several 1/8" to 3/16" holes in the bottom for drainage.

2) Tomatoes will need, at bare minimum, 5-gallon containers to grow big enough to produce well. Herbs may be grown in shallower, pan-shaped containers. Other crops such as lettuce, onions, carrots, ... need at least a foot of soil depth to grown in.

3) I like to use a spreadsheet - such as EXCEL or the one that comes with the free Open Office suite to keep track of my activities. Data such as which plants you started on what dates, where you bought the seeds or seedlings, how many seeds you planted, how much yield you got, ... are all useful to remember and learn from for next year's planting. Many of my plants are started indoors - that is also recorded, along with dates they were transplanted outside.

4) Recording how many seeds planted will help you to track germination rates. If you planted 10 of a certain seed and 2 actually come up, you know you are either doing something wrong or else have a poor quality seed supplier. Many of the seeds bought at big box retail outlets are of poor quality - if you can obtain the "heirloom varieties" they often germinate better and produce a tastier product, too.

5) Heirloom v.s. hybrid seeds - will often store longer than the commonly available hybrids under similar conditions. 2,000 year-old grains taken from Native-American burial sites have actually germinated and grown into mature plants! Seeds harvested from the traditional heirloom plants may be saved and used for next year's planting. This is what folks did for thousands of years prior to modern scientists playing with the genetics of plants and domestic animals.

Hybrid plants often produce seeds that cannot be saved and used for next year's planting. The reason for this is the genetic manipulation used to produce the hybrids - often the offspring are sterile or else loose some of the characteristics they were bred for. This is a great boon for the seed companies - you are basically forced to re-buy seeds EVERY year. Burpee, American Seed Company, and Monsanto are laughing all the way to the bank!

Hybrid plants are often more vulnerable to being TOTALLY wiped out by a disease or pest because of their lack of genetic diversity. With NORMAL plants, a plague may wipe out MOST of them, but there will usually be some individuals that, due to their genetic differences, will survive and reproduce. With hybrids, you have an ENTIRE field of plants that are genetically IDENTICAL to each other. ALL of them will have the SAME WEAKNESSES, as well as the strengths they were bred for. So, if they happen to be susceptible to a particular disease that strikes in a given year, it's likely the crop will be utterly wiped out. While hybrids weren't around back then, the Irish Potato Famine was in large part due to the extremely limited genetic diversity of the crops being grown at the time. Same with many other devastating crop failures around the world.

6) I start seeds indoors when possible. This allows me to more tightly control lighting, water, and temperature to help assure proper germination of the seeds. Some I plant in dirt; some such as beans I sprout in wet paper towel placed in sweater boxes, then plant in dirt later. This sprouting technique is a sure-fire way of seeing early on what is germinating, since they are not covered up with dirt.

Last year I planted some hybrid beans, spinach and lavender seeds (these were all I could get on short notice) outdoors - NONE of them germinated. We had a lot of rain and unseasonably cold weather which could have messed things up. This year I just planted some in dirt indoors. I also have some in wet paper towel to see if they sprout there. I'll see if either set of these germinate. I bought these last year from either the local home improvement store or Wal-Mart (I can't remember now - a good reason for record keeping as described above). If they don't germinate within a reasonable time indoors I'll scrap them and get some others.

7) Introduce natural predators such as lady bugs and praying mantises. These are available at better garden supply stores. When deploying these, do so at dusk AFTER spraying the plants with a mist of water. They'll then be more likely to hang around and feed on the aphids, spider mites, ... These GOOD predatory bugs also like being around aromatic herbs - yet another reason for having these mixed among your vegetables.

Tomatoes and Red Spider Mites
In the interest of protecting the environment, the makers of "Seven Dust" have made their product ineffective against the red spider mites that ravage tomato plants. For several years I have used an "all natural" orange oil based liquid household detergent (bought at Wal-Mart) mixed 1:4 with water and applied to the affected plants with a pump spray bottle. A few minutes after application I use a garden hose with a spray nozzle to CAREFULLY blast the bugs off the plants. With practice one develops the right "feel" to use enough force to remove the bugs but not damage the leaves and blooms on the plants. This process removes most of them. I do this during the hot, dry part of day when there are fewer of the natural predators, such as lady bugs, present.

This technique is also useful for other types of pests as well. There are commercially made insect removal soaps made for this purpose, but I get by with the "poor boy's" remedy described here. I have read that a dilute dish soap solution works for this, too.

Recommended Reading: Look for the book "Square Foot Gardening" - the techniques work for either container gardening or more traditional gardens and will vastly increase the yield in a given area.

Testing Your Login Security

Most folks log into their internet service accounts, email accounts, ... assuming their passwords are secure against prying eyes. Sadly, many of these accounts transmit passwords "in the clear" - meaning that anyone nosing around on the network could potentially grab your account information and conduct all sorts of nefarious activities IN YOUR NAME. Even some banks and other sites that deal with financially sensitive matters still don't adequately protect your login information. This is how folks end up having their accounts hijacked and even being locked out of them. No doubt this contributes to the rising tide of ID theft cases we hear about in the media, news reports, ...

A Potentially Eye-Opening Experiment
Here's a good exercise for the proactive reader:
Install a good packet sniffer such as Wireshark on your PC. There are other packet sniffers besides Wireshark, but this is widely available for us LINUX users, is full-featured, and works well. Simply Google "packet sniffer"+"whatever name of your operating system" for software that should work for you.

After installing the packet sniffer, start it and get familiar with its interface. When you are comfortable using it, open a separate window and log into your email account, or blog account, ... and watch what happens. Using Wireshark, one can see whether or not the communication is encrypted - as it will tell you so. If the data is properly encrypted you will see "gibberish" in the "capture window"; THIS is what you want. If it isn't, the data sent - likely including BOTH your screen name AND your password - will appear readable in the "capture window". If this is happening you are a sitting duck for someone hijacking your account!!

What To Do Now
At this point you MAY want to consider complaining to the provider of the service in question. It is inexcusable in these times for logins to not be properly encrypted! That said, you will want to CAREFULLY word your complaint - as most folks are still woefully illiterate where computers and the Internet are concerned and you DO NOT want the entity to which you are complaining to think YOU are hacking them! You could do as I did with my ISP a while back (see my previous post) and allude to some "diagnostic software" that turned up the problem. I've found that being tactful, but firm, works best. "Your mileage may vary", but until enough people complain loudly enough to ISPs, account providers, and software vendors, we will continue to suffer with shoddy, insecure systems and services. If you have a choice you can always switch providers.

Legal Issues
I want to emphasize the need to use packet sniffers and other such tools in a LEGAL manner. It is legal to use these "hacker" tools to test and "harden" your own PC or network, but using them on anyone else's systems or network without expressed permission is unethical, illegal, and potentially dangerous.

Usage Considerations
After conducting a test using your packet sniffer - shut it off. Packet sniffers can, in some cases, cause security issues of their own, so use them judiciously.

While what I have just described does NOT, by far, address ALL possible compromises to your online identity, this one is a BIGGIE.

A quick Word On Firewalls
Many folks still do not use a firewall to protect their computers - but they should. In simplified terms, a firewall is a piece of hardware or software that allows certain types of communication between your PC and the Internet, while stopping other types of traffic. Some firewalls strictly do "packet filtering" - while others, namely some software firewalls, also have settings that control which applications may access the Internet. For firewall software, windows users can choose from Zone Alarm, Black Ice Defender, Trend Micro, and a number of others. Most, including the firewall that ships with windows, have well-documented problems. There are sites on the Internet which compare them; some prior research can save money, time, and headaches. Many DSL "modems" and even some wireless (wi-fi) access points contain a "hardware" firewall. The advantage of the hardware firewall is that it is physically between the Internet and your PC - so many problems may be stopped BEFORE they ever reach your PC. In order to do their job, hardware and software firewalls must be configured properly. Many firewalls, when left in their default configurations, do NOT adequately protect you against some common attacks.

It is beyond the scope of this post to detail configuration of all the different firewalls out there; you will want to do your own research and consult the instructions with whatever system you use.

In a later post I will discuss some methods you can use to test your firewall.

Thursday, April 1, 2010

Tools For Testing Your Computer and Network

Late last Fall, I completed some on-line courses on PC Security. These were quite interesting, and enlightening. Eye-opening would not be an exaggeration. The "advanced" course covered tools such as "wireshark" - a packet sniffer, and "nmap" - used for probing a PC's software ports. The lesson on using wireshark came at a very good time, as I shall describe below.

Diagnosing Slow Internet Service
Wireshark, and other packet sniffers such as "TCP Dump", are used to monitor data as it passes across the network. A packet sniffer will tell you if packets are being dropped, re-routed, and will tell you the IP address of any routers or computers involved in the connection. Within a week after I had gone through this lesson and installed wireshark on my LINUX system, my Internet connection slowed W A Y down. The term "glacial" was an understatement - with throughput falling below that of 56K dial-up. I verified this using several sites on the web which test your connection speeds. When I fired up wireshark and attempted to navigate to a web site, I saw that MANY packets were being dropped - both at one of my ISP's routers as well as at a DNS server. Ping times were in the seconds, in some cases, but averaged around 700-800 milliseconds. Armed with this information, I was able to avoid the inevitable lame questions such as "Have you cleared your browser cache?", or "Have you tried rebooting?", ... when I called my ISP's tech support line. I was able to talk intelligently with the technician, citing the data I gleaned from my earlier wireshark session. During my 30 minute call, the technician identified a configuration problem at their end and fixed it. One word of warning: Wireshark and nmap are both legal when used properly and ethically, however they ARE considered "hacker" tools and should be used with CAUTION. If you are trying either of these on your work PC you may well get an angry phone call from your IT department - or even face discipline! ASK IT's permission FIRST if you are legitimately wanting to do this on their network for educational purposes. Your ISP also will likely take a dim view of your running these tools from home to probe other machines on the Internet, figuring you're engaged in nefarious activities. My ISP didn't ask me what "diagnostic tools" I was running prior to my talk with tech support, so I didn't tell them.

Testing Your PC's Security and Firewall
Recently, for my continuing IT education, I bought someone's cast-off copy of Windows VISTA "Home" edition. I partitioned my newest machine and configured it to dual-boot my choice of VISTA or LINUX. Soon, I plan to run my OWN tests of VISTA and its built-in firewall by probing it with another networked LINUX box loaded with the nmap port scanner. Since both machines contain LINUX systems, I can effectively use either box to test the other's firewall configuration.

Removable "Drawers" for Quickly Reconfiguring a PC
Removable hard drive "drawers" allow you to quickly remove a physical hard drive from a computer through the front panel WITHOUT opening up the case. With this, you can use a computer in multiple configurations and OSes - it's like having several PCs, only MUCH cheaper! For example, on the dual-boot VISTA box I mentioned above, I have a Win 2K/LINUX dual-boot drive and the VISTA/LINUX dual-boot drive. Each drive is installed in its own drawer and can be swapped within a few seconds by powering down the PC, removing the one drive and inserting the next one. One drive/drawer may be used for software development while another can be reserved for general browsing, multimedia, or whatever. I have several small, <10GB hard drives left over from 10 years ago. I'd like to get another couple drawers for these and use them for certain types of testing in my lab. Loading one with LINUX and Apache server would be VERY useful for testing one's web pages BEFORE going "live" with them on-line.