Best Axial Hotwire Bulb?

donn_

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I only have experience with FiveMega's little 11V 22W Axial bulb, which I run in a 3-cell Surefire. It has a gorgeous beam, and I'd like to try an axial in one of my Mag hotwires.

Any suggestions for a good compromise between powerful output, long life and price?

Thanks in advance.
 
A lot of people have done mods with the 64458 and 62138 (USL!). Though if by "long life" you mean "long battery life", neither is going to suit you.
 
Fivemega sells a 6.6V 3.3A bipin axial, a little less bright than an ROP. Not driven hard on 2 big Li cells.

There is the Osram 64275 6v 35W. good for 6AA. Easy to blow on big LIions.

Osram also makes a number of 12V Axial GY6.35 bulbs from 20W on up. Most of these are rated as 4000 hour bulbs so you need a big overdrive to excite them.
 
Bless bulbconnection.com!

I ordered 458s and 5051s on the 22nd and they were delivered today.

I like the beam from the 458, but I have the same problem with it as I have with FM's little axial. When I focus it down to a good hotspot, I also get a single dark line going out from the center. The tighter the hotspot, the more apparent the dark line.

What's up with that?
 
Bless bulbconnection.com!

I ordered 458s and 5051s on the 22nd and they were delivered today.

I like the beam from the 458, but I have the same problem with it as I have with FM's little axial. When I focus it down to a good hotspot, I also get a single dark line going out from the center. The tighter the hotspot, the more apparent the dark line.

What's up with that?
Mine does it too. I believe the line may be caused by the heavy filament supports.
Billy
 
I seem to have solved the dark line problem. I shortened the legs on the KIU socket, and the line disappeared with the lamp at a lower level.

I've also now tried 440s in the light, and they're just as nice a beam as the 458, just not as bright.

I'm running the axials in my latest FM concoction; a 3.5" head on a 5x26500 tube with an AW soft-start. It's a great combination.

Does anyone know of an axial bulb which is hotter than 100W?
 
All my hotwires use KIU sockets, so that's the limit for bipin legs.

22.2V nominal is my biggest so far (6S Emoli 26670) but I'll be putting together a multi-18650 light when Jonathan's exotic coating project is finished, using his 4" head and a Mammoth tube. I could go to a max of 12 cells in that one.
 
Here's my 458:

IMGP3198.jpg


I got the head in a trade, some time ago, and just bought the tube. I'm really pleased with the color match, considering how much time passed between the making of the two parts.
 
First of all, pick a battery pack. This is probably the hardest item to find right now. The Voltage multiplied by the Amp-hour rating will roughly determine how much energy (and thus with the pairing of an appropriate bulb, run-time) you're going to get from the pack.

The best bet right now is to buy one of FiveMega's adapters (3-wide) or (4-wide [REQUIRES BORING OUT THE TUBE]) or to build your own if you are handy with a soldering iron. I'm not sure if the adapters are stackable, so you want want to send him a PM regarding that.

I do not recommend messing with Li-Ion unless you absolutely know what you are doing!

If you're going with high-powered bulbs (over 5-6 amps, I believe you'll want to acquire some high-current cells, do a search for Titanium and Elite AA and see what you find)

Now, pick a bulb given that you know your bulb voltage. Note that NiMH fully charged voltages are (1.4-1.45V) so they MAY instaflash your bulb. Take a look at LuxLuthor's Destructive Incan Bulb Tests. The place where I get my bulbs from is Bulb Connection

Transverse vs Axial doesn't really matter until you go into the higher powered (> 30watt bulbs). The lesser powered bulbs have a smaller filament so it more closely approximates a point source relative to the size of the reflector regardless of which direction the filament is facing.

Next, pick a socket/switch. I'd recommend one of AW's Mag D Incan Driver - Soft Start & Multi-Brightness. The three levels are pretty useful when you're running one of the lower-powered hotwires (with high-powered hotwires, you don't stand to gain that much run-time anyways), and the soft-start helps those severely overdriven bulbs (such as the 9xAA WA1185). Another good one is JimmyM's Programmable Hotwire Regulated Driver drop-in for D-M@g.

Remember that you'll also need Borofloat lenses (I believe Lighthound also stocks AW's driver if you don't want to wait for shipping from Hong Kong) and an Aluminum Reflector (anyone know where to source these, the only place I can find is KaiDoman and I've decided that the 2 month long wait isn't worth it :shakehead)

However, I've notice a huge difference for the quality of the hotspot between a 64458 and a 64633 (both are driven to around ~200W). I'd take beamshots but I'm too busy playing with the FM3H I recieved today :laughing:
 
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Oh wow, I thought lolzertank was the OP.

Oh well, consider it a how to build a Mag hotwire in 15 minutes :crackup:for anyone else stumbling on this thread. (If you consider it off-topic I'll gladly remove it)

I think the 64458 was the highest powered bulb I could find that wouldn't damage the KIU socket (I'm seeing singed edges on the side of sockets), but 5S Li-Ion seems a bit too much for it.
 
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Here's my 458:


I got the head in a trade, some time ago, and just bought the tube. I'm really pleased with the color match, considering how much time passed between the making of the two parts.

Nice 458 :rock:
One day I need to get one of those soft start switches for mine. I tried running the 440 bulb thinking it would be easier on the switch but not much. Ended up putting the 458 back in.
Billy
 
However, I've notice a huge difference for the quality of the hotspot between a 64458 and a 64633 (both are driven to around ~200W). I'd take beamshots but I'm too busy playing with the FM3H I recieved today :laughing:

And that difference is ..... ?

I'm hoping to make a Mag623 soon, but perhaps a 458 or 633 would be in my future as well. This thread has got me thinking about looking for an axial bulb to compare with.
 
Donn, as far as axial bulbs, I believe the 64458 90W is the highest performing voltage range I have seen. The exquisite IRC bulbs are all axial, but only go up to 65W (64447). From memory, all of the >100W bulbs I have seen are transverse filaments. One other "filament fixing" option was that FM 2.5 Deep with OP texture at the bottom, smoothing out to SMO in upper half of reflector.
 
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