Need some Bulb advice (melted ROP)

[mrmike]

I built an ROP with 6 Sub-C batteries (Elite 4500s in a stick).

It's in a 4D Mag with a 5Mega MOP reflector and a glass lens. I used the light all of ten minutes total (over several times testing it out), saw the reflector fogging up, took the head apart, and discovered this:

I took the bulb out and saw some of the plastic Mag post had melted:

I'm guessing the white stuff is some sort of thermal compound that surrounds the bulb in it's base:

I got a KIU BiPin socket, as I don't want to deal with this happening again.

I was wondering if someone could suggest a bulb that would give me the same output as an ROP. I know with the socket I can use other battery options with higher voltage bulbs... but the 6 Elite 4500 cells in a stick cost a good $60 with shipping, and I hate to waste a battery that has at most ten minutes of use on it. I don't really care if I can't get Mag85 brightness at 7.2 volts, I just want to salvage this light (and be rid of the melting plastic problem).

Any suggestions will be much appreciated... :thinking:

 

[Aircraft800]

Use the Welch Allyn Part Number: 01111-U or simply WA1111, you should have the same Lumen output, and a nice white beam. You can also try the Phillips 5761, a little higher watage.

Both are Bi-Pin, but you'll need a little larger ream on your reflector for the 5761

 

[bfg9000]

If you like the ROP bulb otherwise, there is an aluminum replacement post available now.

The 5761 uses 5.5A (40w) instead of the 4.3A of the ROP High (31w) so runtime may be short, but it's brighter than a Mag85 (36w).

 

[robm]

If you like the ROP bulb otherwise, there is an aluminum replacement post available now.

The 5761 uses 5.5A (40w) instead of the 4.3A of the ROP High (31w) so runtime may be short, but it's brighter than a Mag85 (36w).

NOTE - the aluminum replacement post is for Mag C host. No D version available as yet.

 

[FILIPPO]

I'd suggest to buy both bulbs (WA1111 and 5761) and use them as LOW and HOGH bulb...
when you need a lot of power use the 5761
and when you need runtime use the WA1111


I think that your elites 4500 will not have any problem with 5,5Ah of the 5761 becouse they are high drain batteries and have a good capacity too, so the runtime with both bulbs will be good (just IMO)

:thumbsup:

 

[mrmike]

Thanks for the tips... I just ordered some WA-01111 from Litho, will have to look for a source for the 5761.

:candle:

 

[mudman cj]

Here is a good place to get them.

 

[bfg9000]

NOTE - the aluminum replacement post is for Mag C host. No D version available as yet.

Ah, didn't notice because my Mag Ds are old enough to take C towers. Have C Kiu kits in them right now.

 

[Icebreak]

mrmike -

I'm thinking the lamp will still light up. Is that true?

Would you mind if I captured one of your photos and posted it in the "Race to Failure" thread? It would fit right in as some of us are becoming suspicious of the consistancy of the potting for the ROP lamps.

Let us know how that 5761 works out for you. I've got a 5C ROP with the same batteries and need to upgrade to the 5761.

- Jeff

 

[mrmike]

Icebreak,

Yes, even though the potting compound was all over the inside of the head, the bulb still lit up.

Feel free to post any of the photos on the RTF thread. I need to take some time and read it closely (it looks interesting from a quick skimming).

Note... that white ring around the positive post (the little cap on the end of the spring which you can see with the bulb removed) is teflon tape and not potting compound. I saw someone's previous suggestion that it might help with ROPs in case the plastic does melt in such a way that a short becomes possible.

Mike

 

[Icebreak]

Thanks, mrmike.

It's been posted and makes a good contribution to the discussion. The timing of it in the thread is great.

BTW that WA1111 is about 26 watts over driven while the ROP is over 30 watts. However the 1111 has a very nice color and better beam shape...one of my favorites.
- Jeff

 

[mrmike]

Thanks Mudman for the 5761 connection (I have a few of those on the way too).

Icebreak... I still have the bulb if for some reason someone would want it (it's been laying next to my monitor forgotten in a sea of flashlight clutter). :laughing:

 

[mrmike]

Wow, the Kiu bi-pin socket is really difficult to install!

I just got the WA-01111 and Philips 5761 bulbs; I cut the post off the maglite switch, and was able to successfully solder the negative connection, but how anyone solders a wire to that tiny positive tab on top of the magswitch has my respect. I wound up melting some of the switch plastic before the tab was even hot enough to solder the wire to it... and there's just no room to work with the wires being so short (and having to work with them already fed through the aluminum plate of the socket).

I'm wondering if the metal is different as I cannot get solder to stick to the positive tab (I tore the switch apart once it was damaged, and was trying to come up with some way to solder the positive tab without damaging any plastic). Odd, it has to be something I'm doing wrong.

 

[jimjones3630]

it is tuff, liquid flux usually works fairly well.

jim

; I cut the post off the maglite switch, and was able to successfully solder the negative connection, but how anyone solders a wire to that tiny positive tab on top of the magswitch has my respect. I wound up melting some of the switch plastic before the tab was even hot enough to solder the wire to it... and there's just no room to work with the wires being so short (and having to work with them already fed through the aluminum plate of the socket).

I'm wondering if the metal is different as I cannot get solder to stick to the positive tab (I tore the switch apart once it was damaged, and was trying to come up with some way to solder the positive tab without damaging any plastic). Odd, it has to be something I'm doing wrong.

 

[mrmike]

Thanks Jim... flux did the trick (doh, that should have been obvious, but I was so frustrated with the thing I wasn't using my nugget). :shakehead

I'll have to hit up a Wally World for a clearance Mag C/D so I can strip it for the switch part I busted, but it looks like I'm back in business.

That switch is a "biotch" to build, hopefully next time it should go a lot smoother now that I saw what I did right (and wrong).

 

[DonShock]

....I'll have to hit up a Wally World for a clearance Mag C/D so I can strip it for the switch part I busted, but it looks like I'm back in business.

That switch is a "biotch" to build, hopefully next time it should go a lot smoother now that I saw what I did right (and wrong).

What switch part did you bust? Odds are pretty good I have a spare. It bites having to buy a whole Mag just for a spare part. PM me what you need and your address and I can probably hook you up for free if it's just something small. BTW, if you need individual parts for Mags, here's where I usually get them. But shipping is always a killer for just a single part.

Also, if it's just the positive contact that's hosed, in an emergency you can use the length of ground strap that used to extend up into the bulb post to make a new one. You have to cut that strap down to length anyway to install the Kiu kit. If you use the identical positive contact on the other side of the switch as a template, you can carefully bend the cut off ground strap to match it. It's a hair narrower, but works fine.

Yes, there can be a little bit of a learning curve wiht installing the Kiu kits. One thing I've found that can make it a lot easier is to remove the center portion of the switch and the ground strap. Then I use a chisel to break out the little piece of plastic that divides the two openings in the top of the switch. This way, you can solder the positive contact and the ground nut to the wires while everything is outside the switch. Much easier to do the soldering that way. The larger hole allows the ground screw to be reinserted after soldering.

 

[mrmike]

DonShock
What switch part did you bust?

Looking at Kiu's guide, it looks like you have to solder a wire to the
+ post, through the hole in the top of (what's left of) the mag-tower. I didn't think it would work with all that plastic, but gave it a try and of course it's obvious what happened (cue distinctive smell of molten plastic). :sigh:

So first I was looking for something "more" to solder the positive lead onto; took a needlenose and bent the tab straight (it's sort of folded over). I thought that was a lot better, but I realised I would have to solder the + connection away from all the plastic (and still be able to put the switch back together).

I was pulling my hair out for hours fighting with the switch, until I finally figured out that little red circle in Kiu's guide is a hole cut between the two openings (it looks like some sort of metallic tab in the jpeg, it's really not obvious at all, and I was trying to figure out what I was doing wrong).

So cutting out that plastic bit gave me more maneuvering room. I wanted to take the push button switch apart to get the + metal tab out of it to solder it outside the mag-tower (like you suggested); I assumed there were some sort of locking tabs holding the black/blue parts of the switch together; took a screwdriver and pried up on one of the black "arms" that helps hold down the metallic contacts in place, and of course it snapped off and then I could see the switch is simply held together by pressure. Well that was a $20 lesson (I have a new 4D body with no switch to do something with).

So I did get the switch together finally. 15-35 minutes to assemble? I think I spent 12-hours working on it over the course of the day.

I put the battery pack on the charger... got impatient (after weeks of tinkering, waiting for parts, and probably around $300 I spent on this tube of aluminum, I had to know if it would at least attempt to light), put in a WA-01111, inserted the battery stick (I had only charged it for an hour or so), hit the button, and there was a glorious moment as if the flashlight gods themselves smiled down upon my humble torch... and a half second later the joy was gone.

At least the switch/socket setup is good. Back to charging the stick properly, get some sleep, and I'll play tomorrow (after giving the batteries a bit of a rest).

 

[mrmike]

The Elite 4500s are too much for the WA-1111.

I instaflashed a second bulb after letting the batteries sit overnight.

I instaflashed a third bulb after letting the batteries sit for 2-days. Note this is the same charge from when I completed assembling the light.

I better meter the battery pack... I'm getting 8.14 Volts. The pack in series is supposed to be 7.2 volts.

I'd try the 5761s but I didn't get to reaming out the FiveMega reflector yet...

Well it's no wonder I cooked the ROP (when I had the light in that configuration) if the pack is putting out ~ 1-volt more than it's supposed to.

 

[FILIPPO]

The Elite 4500s are too much for the WA-1111.

I instaflashed a second bulb after letting the batteries sit overnight.

I instaflashed a third bulb after letting the batteries sit for 2-days. Note this is the same charge from when I completed assembling the light.

I better meter the battery pack... I'm getting 8.14 Volts. The pack in series is supposed to be 7.2 volts.

I'd try the 5761s but I didn't get to reaming out the FiveMega reflector yet...

Well it's no wonder I cooked the ROP (when I had the light in that configuration) if the pack is putting out ~ 1-volt more than it's supposed to.

have you done spring resistance fix?:thinking:
KIU socket has a really LOW resistance and you need to add resistance...
you can also try to discharge the battery pack with durable lamps (like 12V 50W 4000Hr). that may help you to put down battery pack voltage

 

[Icebreak]

The Elite 4500s are too much for the WA-1111.

I instaflashed a second bulb after letting the batteries sit overnight.

I instaflashed a third bulb after letting the batteries sit for 2-days. Note this is the same charge from when I completed assembling the light.

I better meter the battery pack... I'm getting 8.14 Volts. The pack in series is supposed to be 7.2 volts.

I'd try the 5761s but I didn't get to reaming out the FiveMega reflector yet...

Well it's no wonder I cooked the ROP (when I had the light in that configuration) if the pack is putting out ~ 1-volt more than it's supposed to.

Dang. That's not good. I would NOT try the 5761 in it then. I'm wondering if that since the batteries are in a pack design it has less resistance than my 5C with 6 series loose 4500s. Also, because I'm using a ROP lamp I'm not using a KIU switch so mine has more resistance.

Even after a rest the pack could show 8.4 volts. At start-up and measured at the lamp it should drop rapidly to about 7.8 volts. Within a few minutes it should drop down to about to about 7.3 then 7.2 and change. I still think there is a possibility that the original ROP failed due to inconsistant potting in a flawed lamp.

Here's a thread where a WA1111 was successful with sub Cs and a 5761 was not.