ROP mod inexpensive, and really bright

allburger

Enlightened
Joined
Jan 7, 2008
Messages
565
Location
Mid Michigan
Well, I built an ROP about 3 weeks ago and I used a 2D maglite, KAI 3aa/1D adapters, Kai MOP reflector, Kai glass, Pelican bulbs, and Rayovan 2500mah nimh's.

The light was fairly bright, but i still wasn't satisfied. I knew that since I was on a budget and forced to use the Kai battery adapters, it was eating up quite a bit of power due to the resistance in the springs.


I also picked up some thin copper sheeting commonly used for crafts at Michaels.

I used my multimeter and found that the problem wasn't in the tin, but rather between the tin and the springs.

So what i did was take the copper and use it to help connect all the springs to the metal on these things. Probably tin.

This is the battery pack with eneloops and the copper resistance fix
0331081702bmr2.th.jpg


0331081704ato2.th.jpg

Rop High Bulb
0331081706ayh1.th.jpg

Rop Low Bulb
0331081708aam3.th.jpg



The advantage to the eneloops with the copper fix is a much brighter light. I put the old batteries back in there with the copper fix and much to my surprise it was also very bright. I gave the eneloops a lot of credit for making it brighter but I believe that it was the copper that helped the most.


I hope I helped someone here who is currently running the Kai adapters.
 
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can I get a more detailed shot of the 1st picture? the one where the actual mod is shown? I'm interested but would like a more thorough process/photo to guide me along.

thanks
 
Alright, by request I am uploading more pictures of the actual mod.

I must apologize for the pictures being low quality. I am using my camera phone because thats all I have right now.



What we have here is the copper going from the negative spring and crossing all the way across the bottom of the adapter. I used electrical tape to tape it to the other side. (The copper is folded and placed between the spring rings. Once the battery is in there, it does not fall out, and i havent had a problem yet.)
0331082124aeq3.jpg



This is a different angle of the last shot. (same spring). This is showing that the copper is just compressed in there. Not soldered. Although that would be the best idea if you can do it.
0331082124blu3.jpg



This final image shows what the other two springs look like. As you can see, the spring is set inside the spring, but on this one, i took a knife and raised the tin just enough to slip the copper underneath it.
0331082124cfm2.jpg




I hope these pictures are clear enough for you to get the idea of what i did.

If you have any other questions/suggestions/comments, please post
 
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I post some more pictures after dinner.


I used the 8.4mm reflector. From what ive read, i would recommend the bigger one because the 8.4mm is kinda ringy

Ok, I want to make sure the ROP bulbs will fit through the 8.4mm opening, correct?
 
Ok, I want to make sure the ROP bulbs will fit through the 8.4mm opening, correct?

Yes, the ROP bulb does fit inside the 8.4mm opening.

Like ive mentioned earlier, the flat spot in the reflector causes rings.

Here is a picture of beam(adjusted camera for brightness to show beam better)

0331082144ayw9.jpg
 
WOOHOO!

It worked!

I built my first ROP - the Shack-Up - using six Energizer Ni-MH cells, a Radio Shack 8AA battery holder, a $2 Rayovac 2D flashlight host*, about six inches of soldering wick, a piece of scrap spring steel for a negative terminal, and a picture hanger for a positive terminal - I got *really* sick of waiting for Kai to ship my ROP parts.

Also - ringy beam? so bleeping what. Those are photons that would otherwise have been converted to heat in your Mag head.

Seems fine with the ROP-low bulb, but the ROP-high caused a little curlicue or two of silver plastic to peel off the reflector within seconds. It is a *spectacular* floodlight, and it throws better than anything else I own save a 8" 12v plug-in spotlight. I am incredibly glad your upgraded cheap ROP works so well, but I think mine is more ghetto :)

* - the 8AA Rat Shack adapter wouldn't fit inside a D Mag due to tight tolerances.
 
WOOHOO!

It worked!

I built my first ROP - the Shack-Up - using six Energizer Ni-MH cells, a Radio Shack 8AA battery holder, a $2 Rayovac 2D flashlight host*, about six inches of soldering wick, a piece of scrap spring steel for a negative terminal, and a picture hanger for a positive terminal - I got *really* sick of waiting for Kai to ship my ROP parts.


Your first ROP!! I like the sound of that. What other variations do you have??

Oh and quick question, do you know of any really nice mods for a 4d mag. I picked up 2 of them at target when they had their sale and im still trying to figure out what to do.

Ill tell ya what i have to work with, i have a mr16 socket with 2 wire leads. The type you see in a track light. I was thinking about doing a stack of washers glued together to form a tower with the mr16 socket on top and the wires running down the holes of the washer. I also have a mag switch assembly that doesnt have a tower because it cracked.

have you or anyone seen anything like this or think this is do-able.

I like to keep this stuff cheap, im in my semester of college right now so disposable income is minimal.
 
No other variations, I'm waiting on Kai to get my stuff here so I can start making things. I'll probably use your copper-bus upgrade on the D adapters and maybe swap out the kludge of a battery pack I made. For reference, "Shack-Up" is: a) memorable, and b) short for "Rat Shack (Radio Shack) Upgrade"

As to your 4Ds, why not make a Polaris? You'd need a bipin adapter, but wouldn't need a reflector since the MR16 bulbs have an integral one. You'd still need a glass lens, but those are fairly cheap. No idea what kind of power you'd need, since there's so many MR16 bulbs out there... if you're interested, it's time for an archive search.
 
Good to hear that you like the copper mod to the kai packs. I assume your a poor college student like I am. Where do ya go to school?
 
UCF. You?

Edit: hey, waitasec, my parts shipped!
Hot diggity!
... I hope the batteries' protection circuit doesn't barf on the 24 watt bulb.
 
dang, i didnt know KAI had AA adaptors, i got one from fm and only later realised there were cheaper alternatives. its okay though, fm's are patent pending...:whistle:

Crenshaw
 
nicely done, I've started modifying my KD adaptors with desoldering wick, but not finished or had chance to do any testing yet. a note to anyone trying the desoldering wick, the solder will travel down the wick so i used mini pliers at the point where i wanted the solder to stop as they act as a big heatsink and stop the flow going right down the wick. looking at testing and calculations on mag tail and switch springs, adding wick down the centre of your springs may improve things further.
 
The better results might come with the eneloops. They have much lower internal resistance than commun cells. I measured 50mOhm on mine while my Sanyo 2700 have 200-300.
 
for the 4D, there are a lot of options... I'm prototyping a switch assembly specifically designed to be used with MR-16 lamps, (loose socket, the lamp is held in place by the head of the mag)... The advantage would be semi-drop-in solution that can handle serious power without any soldering or fancy stuff.... I should have something ready for sale in the next few weeks I hope :)

I'm having a blast right now using a prototype of this switch assembly coupled to 16AA eneloops powering a 12V 50W spot MR-16. The result of the overdrive is close to 100W of really nice white perfection, it's like a wall of light. More lumens than most spotlights, but more floody, lighting it up in a small room can be painful to the eyes, lol.
 
Oh and quick question, do you know of any really nice mods for a 4d mag. I picked up 2 of them at target when they had their sale and im still trying to figure out what to do.

Get 4x 3AA to D.
Get bi-pin to PR2 adapters.
Get glass lens.
get aluminum reflectors.
Get a 12v 20watt halogen bi-pin.
 
Yes, the ROP bulb does fit inside the 8.4mm opening.
Like ive mentioned earlier, the flat spot in the reflector causes rings.
Also - ringy beam? so bleeping what. Those are photons that would otherwise have been converted to heat in your Mag head.
Just something to note. The FM reflectors, while more expensive, do not have that flatspot. They curve all the way to the base. As a result, they do not produce that ringy beam. I have both.

I have had great service and experiences with both sellers and recommend buying from either unreservedly. That said, the FM reflectors do produce a better beam.
 
for a standard 12V 20W halogen, like the type you buy at the hardware store, it takes 15-16 NIMH cells or more to get them to "wake up" enough to be worth running. For 12 cell operation in the 4D, the trick is to order a 12V halogen from a specialty supplier that will run good and hard on 12 cells... Something rated 12V with around 100-500 rated hours life will often work, the 100 hour bulbs will be more apt to pop, the 500 hour bulbs will last around 50 at that overdrive.
 
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