Need some help, what's wrong with my poor-mans ROP?

I've been scrambling the cheapest parts available for a ROP here and there for the best part of a year now(yeah, I know that's not the best way of getting a working ROP, but funds are meager as a student). So I finally got some cheap 3AA-to-D-adapters from Kaidomain yesterday and eagerly(remember, I've had this brewing for almost a year now...) set the whole thing up. I guess you allready have anticipated my dissapointment after I turned the light on. Nothing, nada, zit, rien happened.

So could anybody help me out what's wrong now?

The relevant parts (I guess) are:

1. One very old maglite 2D. It's been sitting around for a long time, but works fine on 2Ds on the regular bulb and a LED-dropin I tried.

2. 6 Fujicell 2700 mAh NiMH AAs from lighthound. I heard that they are not the best, but that's what I've got to work with. And they have been fine in other applications.

3. 2 3AA-to-D adapters from Kaidomain. I'm guessing these are no way close to Fivemegas adapters (just saw the thread with the comparision) but I thought that they would at least squeeze out a couple of lumens out the front. When I tested the voltage in series with the adapter, I got 8,14V. Could someone tell me what the ROP-bulbs are rated at? Or is it something else I should look for. I have a very cheap voltmeter we got on our basic electronics course(which I barely passed), but not sure how to use it to look up other stuff.

4. And last but not the least, the bulbs. I've had a package of ROP-bulbs sitting in a drawer for ages. They seem to be fine, filament is intact and so. Is there some way to check if it's something wrong with the bulbs. I don't think I have fried them, cause I didn't hear or smell anything when I turned them on, but I might be wrong.

Which one of the above is it that is the fault? Or am I barking up the wrong tree entirely?
Thankfull for any kind of help here.

Lobo, I had similar trouble when I set up my ROP, if you put the Pelican light in and try two alkaline D batts, the bulb will glow slightly if it is a good bulb. Check and see if the wrap on any of your AA batts. is ripped, that is what was wrong with mine, mine ripped because they were very tight inside the barrel of the light. Hope this helps, if not someone here has the answer and will help you out.

I'll bet I know. The DX 3AA-1D battery adapters don't have a very elongated ( + ) nipple . Depending on the spring of the switch, they might not be making contact. I built a baby ROP for my Dad with a 5 cell Magnum star bulb, 2 of these DX 3AA-1D batt adapters and 6 energizers, and had to put a magnet on the nipple of the first adapter that went in the batt tube so it would make contact.

Bob

Those KD battery holders have a very flat battery contact on the front. And the positive contact spring in the Mag sits in a little recess in the bottom of the switch. Since there is no protruding nipple on the KD holders, it won't make contact with the spring. But there is a simple solution. All you have to do is remove the switch from the body and stretch the spring slightly so that it protrudes from the recess enough to make contact.

BTW, although the build quality on the KD holders is orders of magnitude poorer than the Fivemega ones, they work fine. I have used them for ROP and Mag85 builds and to my eye the brightness is about the same as the same lights built with FM packs. When shining side-by-side, you can see the difference, but when shining alone it's tough to decide which pack a light has.

I agree with Pokerstud, it's the adapters not making contact with each-other and possibly not making contact with the contacts in the flashlight.

1. Install the 2x 3AA-to-D adapters with battery,
2. Take out the bulb,
3. Power ON, Check the voltage from bulb holder by voltmeter.

If your setting is correct, it should show you the ~8V, right?
Mostly is the adapter problem, take a closer look.

Thanks for all the advices, guys!

I checked the voltage in the bulb socket and it's most definitely the nipple.

So now to question nr 2, how do I remove the switch from the body?
Or is there an even easier way with household appliances. Can I put some tinfoil etc on top? Will that hurt the performance?

Use a copper wire make a small donut, solder it to the top of you adaptor, that is.

Lobo said:

....So now to question nr 2, how do I remove the switch from the body?........

Click to expand...

Remove the rubber cover from the switch button. It is just held in by the edges fitting into a little groove. Then use a 2mm (or 5/64") hex wrench to loosen the ground screw holding the switch in place. Put the wrench in the hole in the middle of the switch to loosen the screw. Use the long end of the wrench, the screw is all the way at the bottom of the hole on the opposite side of the body. Just loosen the screw until it is free spinning and you can remove the switch out the bottom of the light. If the switch sticks in place, leave the wrench in the hole and use it as a lever to rock the switch side-to-side to break it loose.

I'm afraid that I have neither a 2mm hex wrench(the smallest I have is still too big) or a solder at my current location. I'm going to try some tinfoil or a paperclip. But thanks for the help, I'm gonna try both over christmas when I'm at my parents place.

the not-making-contact answer is absolutely correct, I had the same problem and fixed by putting in magnets (also sold by DX and Kai) at the positive end of the adapter.

Actually I have the same set up like yours. The first time I turned it on, no lights. Then I noticed that the spring from the mag are not making contact with the battery holder. So, I got a long nose pliers then I kinda bent the top of the tail spring inwards, it worked.