So you have decided to add a primary HID/LED light to your equipment bag. There is a significant investment to purchase primary lights. They don’t come cheap. A good quality primary light can cost up to $2,000 USD, even more for high powered video lights. You need to make sure your investment will last as long as possible. One of the preventative maintenance procedures for checking the health of your primary light is to burn test the battery. Burn testing the battery is a simple procedure, but does require some time. This will give you an accurate measurement for how long your battery will hold a charge.

Before we go into the procedures about how to perform this test, let’s take a look at why you should be doing this test. The burn test will give you a pretty accurate reading for how long your light will last on a full charge. For divers who are diving in overhead or dark environments, this is critical as nothing will ruin a cave/wreck dive more than a light failure. For recreational divers, who do not venture into overhead environments, the burn test will tell you the health of your battery. If the consecutive burn test results show that the battery is holding less and less of a charge over time, then you may be purchasing a new battery soon. Batteries aren’t cheap either.

How often should you burn test your battery? That depends. If you are a recreational diver, staying out of overhead environments, performing the burn test once or twice a year is prudent. For cave and wreck divers, a highly reliable primary light is very important. These divers should burn test their batteries more frequently. I have found myself burn testing mine two to three times a year. Now that I will be doing more cave diving in the winter, I’ll probably end up burn testing mine four or five times a year.

There are some simple tools you will need in order to perform a burn test:

• Your light head and battery
• Volt meter or multimeter
• Timing device
• Bucket of water (for your light head)
• Uninterrupted free time

Burn Test Procedures

1. Place the light head into a bucket of water. HID lights specifically need a way to remove the heat buildup from the bulb so that no damage occurs to the bulb. A bucket or sink of luke warm water is sufficient enough to keep the bulb cool. Just make sure water stays in the sink or bucket.
2. Connect the battery to the light head. Leave the battery out of the canister. This will make it easier to connect the volt meter to take readings.
3. Connect your volt meter to the battery. Most volt meters have simple metal probes. Make sure that you stick the probes far enough into the Anderson connector to get an accurate reading. If your light head connects to the battery with some other form of connector, then make sure you can attach the probes to the wire. Once the probes are connected, take your reading from the volt meter and record the reading. If this reading is at 10 volts or below, your battery is most likely bad.
4. Turn on your light head. Take another reading with the battery under a load. This will be your starting voltage. Set your timing device to alarm after 10 minutes.
5. At every 10 minute interval, take another reading with your volt meter and record the reading. Stop taking readings when the battery’s volt reading is at or below 10 volts. Do not leave the battery unattended. Once the battery drops below 10 volts, it will start to drop more rapidly. You do not want the battery to drop below 10 volts.
6. The total amount of time it took to get down to 10 volts will be how long your battery will last. I record this time and the date of the burn test on a piece of duct tape on the battery. This way I know how long the battery will last so I don’t get it confused with other batteries I may have laying around.
7. Recharge the battery immediately

You don’t want your battery to drop below 10 volts or completely discharge. Doing so can damage the cells inside the battery pack. For this reason, if you do not use your light for a long period of time (like over the winter), you should place the battery on a charge occasionally.

It should also be noted that the minimum discharge voltage may differ for battery packs from different manufacturers. For example, some manufacturers for lithium ion battery packs recommend the batteries to not go below 8 volts. However, never taking a battery below 10 volts is a good guideline. See the manufacturers recommendations prior to conducting the burn test on your battery.

The burn time for your battery will vary depending on the light head used in the test. My primary light is an 18 watt light head. This light head will consume more battery power than a light head with a 10w rating. While a 10w light head may give a burn time of six hours or more, my 18w light head gives me a burn time around four hours. A light head with a higher output, will consume more battery life and give a shorter burn time.

There are devices that you can hook up to your computer that will analyze the battery. These analyzer can control the burn test process such that the battery doesn’t become complete drained and preventing damage to it. Certainly a nice tool to own. I’ve seen some of these selling for about $200. If I had more lights, this would certainly be worth the investment.

Primary light photo copyright Halcyon – http://www.halcyon.net/lights

Broken Compressor Piston

My “Oh Shit” Moment

I call up the manufacturer and order a new bolt. They also gave me some tips on how to get the thing installed and wished me luck. A few days later, the new bolt arrived. As I started to dry fit everything, I noticed that the piston was binding on the first stage head (i.e. hitting it). So I adjusted the rod length and got it to work. As I was adjusting it, I noticed that a nut that locks the piston on the rod was not tight against the piston. I was able to turn it by hand. This didn’t seem right. So I call the manufacturer again.

They recommend that I remove the piston from the rod, apply some Loctite and put the piston back on the rod. As I was removing the rod from the piston, I saw that the threads coming out of the piston were very shiny. This can’t be good. Once I got the rod removed, I could see that the threads were fine, but there was metal inside the threads. Anyone want to guess where that metal came from? You guessed it, the hole on the piston where the rod screws into was completely stripped out!!!

Another call to the manufacturer was in order. I asked if I could tap out the hole and they recommend that I didn’t as it may weaken the material (since it was already screwed up). They told me that I would need a totally new piston/rod assembly. So my next question was, “How much does that cost?”. Answer, $210 plus shipping. Oh, and I needed new piston rings. At an additional $60 expense.

So now, I’m into this fix for over $350 (including the new bolt I had to buy). I had dreams of getting an O2 analyzer to finish off the Nitrox stick and some additional money for a backup dry suit. Looks like that plan will change. Did I mention that this winter I’ll need to replace the third stage piston as part of it’s general maintenance schedule? I need a job, just to afford owning the compressor.

Sorry for the rant.
Duane Johnson
Precision Diving

When my wife landed her new job, we were extremely happy. We were hoping things were turning around and would go back to normal. Unfortunately, her new job didn’t pay as much as the old one. Facing this deficit in our monthly income, it has forced me to make sacrifices. I have had to work at the shop more than normal just to get some extra cash each month. It is not fair for me to ask my family to continue to dip into our life savings, just so I can go scuba diving.

Since I am not able to teach as much, I will not be able to afford my instructor insurance due at the end of June. Therefore, I will be no longer be teaching scuba diving after June. Before the cheers and boos gets to loud, it gets worse. The money I make from teaching scuba diving goes to pay for my own personal fun diving. If I’m no longer teaching, I will no longer be able to afford to go diving. So I am hanging up my fins. In scuba diving, we must prioritize events in order to make it to the surface safely. This is also true in life. There are higher priorities than scuba diving and this was an easy choice for me to make.

For those equipment jackals out there, a complete list of my gear is listed below and is for sale as of July 1. Just make an offer. Reference the date of this post.

Thanks to everyone who has supported me in the past. Your friendship and well wishes are greatly appreciated. I hope everyone continues to dive. Remember, regardless of what goes on in the diving “industry”, diving is still a wholesome activity and doesn’t deserve to be sold out.

Dive Safe,
Duane
Precision Diving

Equipment List

Like many Americans, this year has been very tough for my family. Last year I lost my job as a business manager at Motorola. I became a stay at home dad for our two daughters. This year, my wife lost her job as a career coach at Deloitte and Touche. As of this writing, neither of us have found a steady job yet. I’ve been teaching college classes part time for some extra cash. As Christmas approaches, we have had to make hard decisions as to what kind of gifts we will get the girls. As a parent, you want to give your kids everything, but many times that just isn’t possible. As I’ve thought about Christmas for my kids, I’ve thought about other people who are in a similar, or worse, situation than me and how this affects their diving Christmas season.

Obviously, it doesn’t matter if I’ve been good or not this year as we can’t afford to get us any presents. As I’ve been thinking about what to get the kids, I’ve been thinking about what kind of scuba presents I would like if we had just a little extra money. Below is my list.

• One of those portable work benches to gear up on
• Some kind of mat to put down on the ground so my dry suit doesn’t get dirty when I’m taking it off. Dive Rite has a nice one.
• Six inch HP hose
• Another Halcyon Scout backup light (Xenon not LED)
• Catheters, because you can never have enough
• A backup oxygen analyzer sensor

Of course, if money were no object, I would want more tanks, regulators, helium, scooter, etc. But I don’t live in a perfect world.

If you had a little extra money to spend in diving, what small items are on your Christmas list?

Dive Safe,
Duane
Precision Diving

I get asked many times about what kind of doubles people should get when they want to move into technical diving. Should they get 130s, 100s, 120s, or aluminum 80s? There is no one right answer for selecting which size tanks. However, special consideration must be made in regards to selecting the manifold, valves, and bands to build that set of doubles.

Selecting Tanks

Double Steel 130 and Aluminum 80 Tank Configuration

I do get a bit of ribbing from folks who think AL80s are “girlie” tanks. Don’t make the mistake and think that double AL80s are not a useful configuration. Sure, you don’t get the extra weighting that comes with steel tanks. But they are easy to handle when on land. Especially if you have a long walk; on a hot day; in a dry suit, to get into the water. Double AL80s give approximately 175 cu ft. of gas. This is plenty for a day’s worth of diving at my favorite quarry without needing to get more air fills. AL 80s are great tanks for beginners because they are cheap and easy on the back.

If you do decide to get AL80s for your doubles, you don’t need brand new tanks (i.e. original hydro dates less than 2 months old or whatever). A set of new AL80 doubles will cost between $500-$700 (with manifold and bands). Aluminum tanks fail visual inspection far less than steel tanks. So the AL80 will last you quite a while. Pick up a couple used AL80s to double up and use that extra money you saved from buying new tanks and put it towards a quality manifold and bands.

Choosing the Important Stuff

I like two manufacturers of manifolds, Halcyon and Dive Rite (only the VA3000 series). Both are very similar in design, the knobs turn easily and can be closed/opened in five turns or less. I once had a Thermo manifold. The chrome plating started chipping off the DIN threads and would lodge in the regulator’s DIN o-ring. Thus causing small leaks. So I’m a little put off by the Thermo and XS Scuba manifolds. I don’t know much about others such as Sea Elite and HOG/Edge. But my preference is the Halcyon and Dive Rite mentioned earlier and I would pay a few extra dollars for them.

Just as important in selecting a quality manifold is selecting strong tank bands. The biggest feature to consider when purchasing bands is the weld. Bands are made in two pieces and then welded together. If that weld is not strong, the bands can break apart. Certainly not something you want to happen with 3000+ psi of pressure in them. Below are pictures of a weak weld and a strong weld.

Bands with Weak Welds

Bands with Strong Weld

It is also important to mention that the bands must be matched with the manifold. Meaning, that if the space between the bands is too big or to small, the isolator part of the manifold will not fit properly into the valves. So make sure, when you purchase your bands, that they are compatible with your isolator. Most will have a sticker on the inside of a band that says which manifold manufacturer will work with those bands.

Summary

Dive Safe,
Duane
Precision Diving

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