PDA

View Full Version : Improving the NiteRider TriNewt's Battery


K'Tesh
01-27-2008, 09:19 PM
http://farm2.static.flickr.com/1167/1474631053_e4e538de72.jpg (http://www.flickr.com/gp/14152252@N02/82WJuD)
click the pic to go to the flickr set I created for this.

First, let me say this... this is an AWESOME light... 486 lumens output with a 3hr 30 min run time on high, 7hr run time on low, and a flash feature.

IMHO, LED lights are going to rapidly replace the less reliable HID/halogen systems that are out there. They are as bright (if not brighter), they run longer, and the lamps are far more durable than HID lamps. In the long run, an HID will cost more than an LED system, just because the bulbs are vulnerable to damage or burning out (and they are not cheap to replace). There's a lot more that could be said, and perhaps that's for later. This is a HOW TO page, and you are not here to get a product review.

A little history is in order... I have several older halogen lights from NiteRider, and I really loved them; they managed to keep me rolling year round, but they had their issues. I'm sure that the LED systems will share some of these issues but likely not all.

One of my first NiteRider lights was the Classic Plus, and it was the light that I kept in reserve. Its run time was not all that I hoped for, but at the time it was the best available for the money. Its water bottle battery was both its strength and its weakness. My bikes have always had two water bottle cages, and I often used only one for beverages. The spare was where the Classic's battery ended up; it was out of the way and easy to access. However, design flaws, a wet winter or two in Oregon, and the times when the battery fell out of the cage during a ride caused its watertight seals to fail. Moisture made its way into the battery and corrosion destroyed the battery (which then destroyed the charger). My second Classic ended up with the same problem: moisture ruining the battery and the charger.

The Problem:

Frame-mount batteries are instantly recognizable as that, increasing the likelihood of theft. If you want to secure the battery, you have to take the battery with you every time you leave your bike in an uncontrolled area. These batteries are expensive and can be a pain to mount and remove. Depending on the routing of your bike’s cables, locating a suitable mounting site can be difficult. Frequent removal of these batteries also increases the chance of damage.

NiteRider's existing water bottle battery design flaws are twofold: keeping water out and, failing that, getting water out. To keep water and contaminants out of a bottle, you put a cap on the outside, not the inside of the opening. Then, if the cap's seal fails, the water will still flow over the cap and away, not be wicked into the bottle by capillary action.

In the event water does manage to get inside your container, it is important to get it out before it can promote corrosion. The opaque, sealed bottle prevents visual and physical inspection, and the foam insulation will keep even a lot of water from audibly sloshing. The only way that I could have found the water without breaking the seal was to carefully weigh the bottle regularly. (Yeah, like that's gonna happen.)

The Solution:

Water bottle batteries are somewhat disguised, reducing a casual thief's chance of recognizing the battery. They can also add a level of shock protection in case of an accident or drop. Mounting one is simple, and the bottle is almost guaranteed to be out of the way. (I know that there are bikes out there that have geometries that won't allow for water bottles, so this isn't for them.)

The TriNewt frame-mount battery is well suited for converting to a water bottle battery; its switch is located on the same end of the battery as the plug's receptacle (as compared to the MiNewt, MiNewt X2, or MiNewt Dual variants, where the switch is located on the "top" of the battery, on the opposite side from the receptacle). Plugging it in and turning it on will be easy. The wireless TriNewt is better, as you don't have to open and close the lid to access the battery mounted power switch.

What you need to re-create my solution:

1 - clear Performance Team water bottle - 500ml
1 - clear Performance Little Wide Mouth bottle - 21oz.
16" - 3/4" wide nylon webbing
2 - 1" diameter split rings (as found on promotional key chains)
Large (toenail-sized) nail clippers
self-adhesive backed velcro
cigarette lighter

The following can be found at better hobby shops:

Gap-filling cyanoacrylate (CA) glue
Accelerator to instantly set cyanoacrylate glue
Hobby knife
Jeweler's saw

You might wonder, why the two water bottles. http://farm2.static.flickr.com/1033/1474534029_03f9c2b8e9_s.jpg

The 500ml water bottle has too narrow a neck to allow the battery inside, but its lid is a perfect shape for allowing the lamp's power cord free movement without straining it. The lid, however, doesn't fit on the 21oz water bottle's threads.

The 21oz bottle was too short to hold the battery without completely removing the top of the lid, but it's neck is wide enough to fit the battery with a little effort. Performance's WideMouth 24oz. water bottle was too big to fit in my bike's frame, and if the battery dropped past the narrowest part of the neck, it would be difficult to extract the battery without destroying the bottle. I chose the clear bottle so I could see if any water had made it inside without having to open it.

The best solution that I could find, was somehow to get the 500ml lid to fit on the 21oz's bottle. I determined that with some cutting and CA glue, the 21oz's lid would fit inside of the 500ml's lid, and thus my plans were made.

I started the conversion by first working on the 500ml lid. I removed the rubber stopper from the lid and kept so I could later use it to reduce the diameter of the hole in the lid that the power cord fits through. Next, the mount for the stopper was removed from the inside of the lid by first cutting the center ring out with the hobby knife, then by using the nail clipper to cut it flush with the inside of the lid. I then cleaned up the inside of the hole by using the hobby knife, and rounded the remaining sharp edges with the cigarette lighter.

Moving on to the 21oz bottle, I removed the stopper from the lid and discarded it. Then using the jeweler's saw, I opened up the lid by cutting the top off, stopping at the inner seal. I then cleaned up the edges with the hobby knife and cigarette lighter.

http://farm2.static.flickr.com/1384/1476178214_e504b8121c_s.jpg http://farm2.static.flickr.com/1229/1474627227_3e03f3d09e_s.jpg

To join the lids together into one unit, I placed the remaining ring of threads from the 21oz bottle's lid inside the 500ml's lid then used the hobby knife to score a line inside the 500ml's lid as a guide to prevent myself from applying too much glue. Next, I scored the area inside the 500ml's lid to give the glue a better bonding surface. Careful not to glue my fingers to the lids, I applied the CA glue to the inside area of the 500ml's lid where it came in contact with the 21oz's lid. After I joining the two lids together, I created a bead of glue around the seams where the lids met. I used the accelerator to instantly cure the glue, thus preventing it from dripping and becoming another problem. To prevent any discoloration of the battery from curing CA glue fumes, do not use the lid for a few hours.

The resulting lid has a tall profile, allowing cable movement and secure attachment to the 21oz water bottle.

I next used the hobby knife to slit the 500ml's stopper down its length. This allows the power cord to be placed inside it. When using the battery, you can lock the stopper in place, and reduce the size of the hole that water can get inside the bottle.

WARNING: To prevent damage to the power cord, do not pull the power cord out of the lid with the stopper locked in place. Always remove the stopper first.

I am still trying to divise a method of completly sealing the battery inside the water bottle, but I haven't figured it out yet. (Perhaps by creating a short powercord to be locked into the lid... hmm). I'll work those problems out later.

To extract the battery, I used 3/4" nylon webbing to create a "leash" to pull the battery out of the water bottle. I simply cut and heat sealed the ends of the webbing to prevent unravelling. To save time and eliminate the need for sewing, I made a loop on each end by folding two inches over from each end, and then used the CA glue to create the loop. I used the split rings from two keychains to create a grip on the loops and to prevent the leash from pulling through without pulling the battery out. When not being used, the leash tucks out of the way into the water bottle, and a simple upside-down shake gets it out for use. Applying self-adhesive velcro on the bottom of the battery,(and a matching point on the leash) prevents the leash from slipping off when extracting the battery.

The resulting water bottle isn't waterproof, but it will prevent most water from hitting the battery. It will also add a level of shock resistance and in doing so should aid in keeping the battery in working shape for years.


Rubberside Down!
K'Tesh

ps. Originally posted at http://forums.mtbr.com (http://forums.mtbr.com/showthread.php?t=344212).

wsbob
01-29-2008, 11:41 PM
K'Tesh, nice work on the slide show.