LED Lightbulbs and antique lamps

[Holly_Hobby]

Hi,

I own 3 very old lamps with slag glass shades. I bought a new LED bulb to try out because I don't have any more of the incandescent bulbs left, and wanted to see what kind of light they throw before I needed one.

The LED is way too tall. I can't replace the harp with a taller one (the thingy that holds the lampshade on) because it would expose the socket.

Any ideas? These lamps are worth a small fortune and have been in my family for over 100 years, and I use them every day. I sure don't want to have to replace them just because of bulbs. Thanks.

[NYC_SKP]

1. I have a wide range of LEDs that I've collected over 8 years or longer.

More and more become available every month- Your problem was also seen with CFLs until they offered more sizes and form factors.

If you shop around between the different home improvement stores you might find the right fit-- Feit, Phillips, EcoSmart and others are sold, but at different stores (not all that Home Depot carry are also at Lowe's, for example).

If you can't find what will fit in a medium Edison base (the typical screw type), you might find something smaller with an intermediate base, and then use an adapter.

Not sure what lighting equivalent you're looking for (40W, 60W, 75W or 100W), but Feit has a range that look smaller than typical incandescents:

[Holly_Hobby]

5. Thanks, n/t

[krispos42]

2. I've spent several hundred dollars at...

www.SuperBrightLEDs.com there past couple of years, mostly on lights for my car, but I've yet to have a problem with then.

they give pretty exhaustive information, including dimensions, of their stuff so your can see if it fits or not.

you can search by base size as well. if yours has a "regular" base, which is the 26mm Edison, you can screw in an adapter to convert it to "intermediate" (17mm) or "candelabra" (12mm) size.

[X_Digger]

3. +1 for superbrightleds.com

There are a couple other specialty lighting sites that I've used, but none as detailed.

[Holly_Hobby]

6. Thank you for your reply n/t

[TreasonousBastard]

4. I'd suggest you look for a CFL that fits...

I know all the talk is about LEDs, but a direct comparison between LEDs and compact fluorescents show very little difference in "wattage per lumen" so there's no effect on your electric bill whichever you choose.

LEDs also have really lousy color. There's something called the "color rendering index", or CRI, used by lighting engineers and designers where 100 is perfect and anything below about 85 is crap. Fluorescents can be found in the 90s, while LEDs are up there are extremely rare and tend to cluster around 70. Incandescents and quartz/halogen are about 100.

And the the price-- 10-25 bucks for a dim bulb with lousy color?

There's no reason why LEDs won't become cost effective and have better light in the future, and some say they should be there now, but for now there's little reason to go there. The one big problem with CFLs in your case is that the more light you want, usually the bigger the bulb, so you are limited in wattage if you want to fit under that harp.


And, incandescent bulbs haven't completely disappeared, just some shapes and wattages. Quartz halogen, which are slightly more efficient than incandescent, might be around forever.

[Holly_Hobby]

7. That's helpful too, thanks n/t

[NYC_SKP]

8. CRI improving more and more, now >90, and LEDs more than pay for selves in life span alone.

New CREE chips:

http://online.wsj.com/article/PR-CO-20140129-910210.html

Cost comparison from 2010:

Students use a table to compare the cost of bulbs and cost of electricity to operate each bulb type for 30,000 hours.

Bulb Type Bulbs needed for 30,000 hours
Total Bulb Cost plus Electricity Used @ 15¢/kWh

Bulbs + Electricity

Incandescent
38 watts 30 $30.00 38 W x 30,000 hr
= 1,140,000 Wh 1,140 kWh $171.00 Total for lamps plus power= $201.00

CFL
9 watts 4.28 $29.66 9 W x 30,000 hr
= 270,000 Wh 270 kWh $40.50 Total for lamps plus power= $69.66

Feit LED
6.5 watts 1 $20.00 6.5 W x 30,000 hr
= 195,000 Wh 195 kWh $29.25 Total for lamps plus power= $49.45

And they're cheaper now.

[TreasonousBastard]

9. The Cree chips are neat, although...

not unique. But, with the drivers and fixtures needed, not exactly what a homeowner needs for a couple of antique lamps. I've seen extraordinary lumen output in the lab, too, but first there are those industrial new builds, then refits and later come the homes.

As far as the calculations for 30,000 hours go-- you do realize that's about 7 years at a 50% duty cycle. And to compare 9W with 6.5W without a lumen count is deceptive, but even if they are the same output, 20 bucks over 7 years approaches meaningless. I probably should ask what "4.28 $29.66" means, but doubt it will change anything.

[NYC_SKP]

10. The copy paste action lost context. 4.28 was the multiplier to reach 30,000 hours.

CFLs are adorable; they're long fluorescent tubes twisted into tighter shapes.

I would prefer we just move on to the obvious solid state lighting model now, thank you.