Butterfly No. 4D 500/600CP mantles

Definitely dangling - but nowhere near so decorative...

 

Seriously though, without any indication I can only assume they are radioactive just in case.

 

Biscuits?

 

An envelope with 30 Butterfly 4D 500/600 arrived today from China.
No indication wether radioactive or not.
Can't measure it. These U shaped 4D are much larger than the bulb shaped 41.

 

To be honest, they are huge, but they work very well on lanterns that take large mantles, like my P'Max clones and the Coleman models, 295, 220, 635, 639 and 201. The size was a little variable but that was useful, particularly as the 201 needed one of the slightly smaller ones. All in all though, I found the performance extremely good and in fact the Anchor 950, 909 and Light Brand 350cp lanterns are now so bright it's painful to look at them!

@bp4willi have you fitted them to any of your lanterns yet? If you have, which ones and how did they perform?

 

... as for radioactivity, I don't think they are but it would be nice if someone with a Geiger counter could confirm this.

 

I've tested these Butterfly 4D mantles(500-600cp). Here's mine:-

 

Errrrrr, can you explain what the result means... and thank you as well of course!

 

Don't bother the measured values. It means they ARE radioactive. Non-radioactive ones measure zero on this.(background radiation already taken into consideration).

 

Oh! That's unexpected, but am I right in thinking that they will glow brighter with (probably) Thorium?

 

Its most likely due to the Thorium content. Of course Thorium's not the only thing that could be radioactive. I've read an early patent by Carl Welsbach whìch stated some Uranium oxide has been included as well.
Well, they may produce a whiter light but I can't exactly tell if they are really brighter without a Luxmeter. So, your eyes would judge best.

 

I guess not.
Buy a lux meter at Aliexpress and build you a lightmeter.

 

I did some side by side testing last week comparing Egret brand Round and U-shaped 300/400cp mantles with each other, and with Coleman #21s in a Coleman 220E dual mantle lantern. The results were interesting. Below is a quote from the Coleman Collectors Forum Mantle Shape "Last night was quite illuminating" Post #46


I did a light fettle on my recent Craigslist find, a 1963 220E (transitional) to use for the testing.

After oiling the pump leather, removing a couple of instaclip mantles, changing the fuel cap (i need new gasket for the original), and adding some CF, I installed two brand new #21s, burnt them in, and lit her up for the first time since I got her last week.






Both mantles burned very well, and kept a good shape.



I then shut off and let cool so that I could do a mantle swap. I removed the left mantle, and replaced with one of the Egret 300/400cp U-shaped mantles. It was quite a bit larger than a #21



After burning the new mantle it in, It was still a bit longer than the #21/



I lit the lantern again, and waited for it to settle in.. The Egret Mantle shrank quite a bit, but remained larger than the #21. However the light output seemed about the same, and the color was almost identical.



I took a closer look, and I don't feel the 220 was taking full advantage of the size of this mantle. Parts of it looked dimmer and the light level fluctuated like it wasn't being filled correctly.



I then turned the lantern off again and let it cool to add the round 300/400cp mantle.





After Burning off, It remained slightly larger than the U-Shaped



Once lit however I was amazed that both Round and U-shaped took on almost exactly the same shape and size. Both seem to be equally bright to each other, and therefore about the same as a #21. I am wondering how these would do on a 200A or other single mantle lantern. I may have to try one next time I get out to my storage trailer.




This is how the 220E looks from a distance with both a Round and a U-shaped 300/400cp Egret mantle. It came in a home made box, and has a broken valve wheel and the Coleman decal is almost completely gone. I can just see parts of the outline. Greg (Gand28) is sending me a replacement Valve Wheel THANKS DUDE!



The Peerless 2c-hg will be here next week, and I will do another comparison then.

 

Or tight-fitting pants, just like a cheap hotel, no b...room...

 

I can confirm,
the Butterfly 4D are as bright as the blue Peerless no.3
Both 500cp mantles.
See, on left Peerless, on right Butterfly 4D. Both Petromax 500, kero.



Regards
Willi

Ps. Search for Tilley AL21

 

Hey guys I am looking for the butterfly 500/600cp mantles to use on northstar propane lanterns and can't find them anywhere.

I was thinking of going with the peerless 24A mantles but I think the butterflys are just a tad larger which might work better with the northstar lantern.

I purchased american mantle specific northstar mantles and even though they are better than the coleman mantles as they burn in better and straighter they are still fussy to say the least.

Any help would be appreciated.

Thanks

Rod