Carley Reflector Report

I bench tested the Carley 1 3/8" 2" and 3" aluminum reflectors.

The 1 3/8 " and 2" smooth surfaces focus to a reasonably tight hot spot with a relatively faint overspill. The filament pattern is quite noticeable outside the hot spot, more so with bulbs with lensed tops. The lensed tops superimpose a filament shaped ziz-zag bar across the hot spot. these reflectors fit well with the common W/A T-2 1/4 lamp length. Both of these reflectors conform to the shape of the drawing on Carley's web site.

The 3" reflector base is deep enough that the normal W/A bulbs are right at the borderline of beeing too short to focus and plug into the socket at the same time. This reflector might require a Carley bulb with untrimmed leads or a W/A bulb like the 01148 that is too long to focus effectively in a DB.

The 3" reflectors outsides match the contour of the interior parabolic or elliptical surface with a comparatively small base cylinder. It appears to have a slightly tighter hot spot than the 2" and probably throws farther.

I will probably buy more 2" reflectors, but don't yet see a reason to deal with the additional mass, cost, and required bulb (or bulb lead) length requirements of the 3" reflector.

I am following your posts religiously, when you get the recipe down for the DB8, I will be ordering my stuff!

Did you re-wire the DB 8 or is is stock?

Thanks for doing this!

BuddTX:

I have both serial and serial / parallel DB8AA's.

Configurations include:

Stock serial parallel with 2 * 4 alkaline AA's driving a W/A 4.8 V 1.1 a 01307 bulb at approximately 5.2 V and 135 Lumens.

Serial parallel with 2* (3 @ AA Alkalines + 1 CR123 Lithium + 1 17 mm dummy), and a W/A 01315 6.28V 1.42 A bulb.

Serial with 7 A NiMH's, a 50 mm dummy, Aragon modded pluggable P91 with plug doubling as a charging port.

Serial with 7 A NiMH's, a 50 mm dummy, external charging port and a a W/A 01315 6.28V 1.42 A bulb.

Stock Serial Parallel with 2 * (3 @ CR123 + 1 Alkaline AA) and a W/A 01278 9.0 V 1.10 A bulb.

If I use a W/A 01148 bulb 6.30 V 1.95 A I may decide to try 7 or 8 cells depending upon observed voltage drop.

The lights with recharging sockets have replacement switch assemblies, although I'm still using the OEM bulb socket portion of the socket / switch assembly. I have been unable to get consistently reliable switching contact with the OEM DBXAA switch on many of the DB's that I've converted to serial. The lights w/o recharging sockets are the ones with switch assemblies I've had better luck in not tweaking the switch alignment.

How heavy are these reflectors, especially the 2" and 3" ones?
Is there any way to figure out at what angle the reflector has? Is there a chance that we might see some photos of the reflector and or beampictures?
What kind of reflector did you buy, the standard ones or that set-screw refletor type?
One last question: what is difference between the parabolic and elliptical ones except for shape?

Thanks in advance,

Klaus.

KT:

I'll weigh them tonight. I am still digital photography challenged, but will try to post pictures at some time.

I've been too busy to set up permanent mountings. I bought the set screw versions so that I can more easily epoxy my bulbs into the retainer sleeves with more precise centering. Also, when a bulb burns out, the set screw versions permit easy bulb replacement.

The set screw versions also allow focusing by sliding the sleeve in and out of the ream hole.

The elliptical reflectors are described as "refocusing"

The parabolic reflectors are described as "collimating".

I guessed that the parabolic might have a cleaner and tighter single hot spot and that the elliptical provided more satisfactory focusing alternatives.

I chose the parabolic "collimating" set screw option. I can tell you that focus was very sensitive to slight position shifts of a bulb placed in a W/A ceramic socket that was loosely finger held and inserted into the reflector ream hole. That experience makes me contemplate about what centering fixturing I might improvise when using epoxy putty to mount the bulbs in the sleeves.

Thanks for that additional info. May I ask what the meaning of "collimating" is? What is the difference beween "refocusing" and "collimating"? I am not very knowledged at things like that.

Thanks, Klaus.

K-T:

I understand that "collimating" implies a single optimal focus. That is why the acrylic lenses provided with LS are called collimators. When not perfectly centered in the proper point on the reflector axis the beam appears relatively imprecise, irregular, and unfocused without a hot spot.

I understand "refocusing" to mean that the shape provides more freedom to move the bulb up and down the the axisx of the reflector to stretch the hot spot from a tight spot to a wide flood.

lemlux,

Have you tried any mods with the Surge? There's plenty of power to work with on 8AA NiMH, and I figure a 2" reflector could be sanded down to the 1-1/2" that the Surge takes.

I've previously measured 2:55 min. runtime on 8 Powerex 1800maH NiMHs with stock bulb, so it would not bother me a bit to double or even triple the power output in order to get a screaming long throw light. I've also managed to singe the plastic reflector a bit doing these runtime tests, so aluminum is a must.

K-T:

The 2" reflectors weigh 1.4 oz.
The 3" reflector weighs 5.9 oz.

Lux:

The ID of the 2" reflector is 1 13/16 -- the outer shell at the edge is only 3/32" thick.

The 1 3/8" reflector is machined from cylincrical bar stock and won't fit inside the Surge battery holder clips.

The 1" reflector ream hole is too deep to give a focus for the OEM bulb.

I also have had reflector center melting problems with the stock reflector caused by alignment shifting of the loose reflector.

I still don't know what other bulbs with longer pins would fit into the pin holes. If I did, I could try the 1" reflector mounted onto a ceramic or fibreglass washer to temperature-insulate the socket PC board.

You might try the PT40 with the Carley 50-hour 3.5V 2.30 A halogen T- 1 1/2 bulb ceramically potted into a PR base. This custom bulb cost me $8.02 including $1.65 potting charge with a 5-potted bulb of mixed types minimum. This runs considerably brighter than the Surge at around 3.9V to 4.0 V with freshly charged 1800 mAh NiMHs.