How to cut glass sealed beam bulb ?

[Sorcerer]

Got this small glass sealed beab bulb that I want to cut the back out of, so I can make it useful with LEDs.
Any ideas or experience in doing this wil be helpful.
Thanks in advance.

 

[Dr. Tankenstein]

Can you post a picture of the back of the bulb?
For the first Auction Bike, I was able to cut the filament off, leaving two holes that I siliconed LEDs into, wired them inline with a switch and a twin AA battery pack.

Hope that helps and makes sense.

Cheers,
Dr. T

 

[CCR]

viewtopic.php?f=67&t=56486&st=0&sk=t&sd=a&start=105#p559446

I used a glass bit to start a hole

and used a dremel with diamond grinders in it to ground out a circle, dipping the bits in water frequently helps.

 

[Sorcerer]

Can you post a picture of the back of the bulb?
For the first Auction Bike, I was able to cut the filament off, leaving two holes that I siliconed LEDs into, wired them inline with a switch and a twin AA battery pack.

Hope that helps and makes sense.

Cheers,
Dr. T

Thanks. I want to take the whole back off and use a new reflector with 16 to 21 LEDs centered for a clean beam of light hitting the lens.
However that may have to change.

 

[Dr. Tankenstein]

If I'm reading you right, you only want to keep the original lenses and house it and a new reflector (w/LEDs) in the shell of the light?

If that's the case, you might try a diamond wheel cutter on a Dremel to cut around the perimeter of the bulb. There may be a lip for you to use as a guide. The glass is probably thicker there too.

All I can advise is to wear leather gloves and go slow. Good luck, take pics so we can see the results!

Cheers,
Dr. T

 

[CCR]

ive seen people dip cotton string in something flamable, wrap it around a bottle and set in on fire, let the glass get hot a bit and then dunk it in water. the heating and cooling cracks the bottle at the hotspot and leaves a pretty clean "cut". but wine bottles are pretty thin. Might take and hour or so but you could cut the lens off using those diamond grinder bits in a dremel too

 

[Sorcerer]

If I'm reading you right, you only want to keep the original lenses and house it and a new reflector (w/LEDs) in the shell of the light?

If that's the case, you might try a diamond wheel cutter on a Dremel to cut around the perimeter of the bulb. There may be a lip for you to use as a guide. The glass is probably thicker there too.

All I can advise is to wear leather gloves and go slow. Good luck, take pics so we can see the results!

Cheers,
Dr. T

Ya that's the idea. Not to sure how stable the lens would be done this way. I'll Need to get a diamond wheel. I tried the string on fire thing , it did not work. The glass is to thick.
I may just do it your way as I don't ride in real dark here in Phoenix. It's bad enough in broad daylight. People try to run over buses here.
Thanks alot for your input.
Arley

 

[Toeslider]

I don't remember exactly how I did it, but I know it can be done. A sealed beam is basically two glass "dishes" that are sealed to each other. I believe I got some sort of diamond hacksaw blade that was used for cutting cermic tile (I think), and handheld it and went around the perimeter of the light, going slowly until I got a groove started, then just kept at it until I had both halfs separated. I remember the procedure, just not exactly what I used, but I think the blade I described is right. This was a light the size of the smaller round quad car headlight, and I remember it wasn't as hard to do as I thought it would be.

 

[NewOrleansFlyer]

I carefully drilled out the filament posts and inserted the leds in the holes...I'm thinking about redoing it though, more lumens may be necessary..

 

[Toeslider]

Here's a couple pictures of the one I did. I believe it got chipped in an unrelated incident:

 

[Supercub]

I used a hacksaw to cut the backside of a bulb out and put an auto spring tab style bulb socket in and it has been good for 7 years now.

 

[LukeTheJoker]

Im not a patient man so I went for something a little faster...

PLEASE NOTE THIS IS NOT A GOOD IDEA FOR THE YOUNGER ONES OF US OUT THERE AND ALWAYS ALWAYS USE A FACE SHEILD AND THICK LEATHER GLOVES! I actually used kevlar lined welding gloves when doing this...

5 inch grinder with a diamond tile blade on it... just cut off the lugs first to vent the vacuum...

DSC00145 by LukeTheJoker, on Flickr
It didnt come out perfectly round, as it broke off before I finished, but it followed the cutline that i was working around and around anyway, so close enough...

DSC00146 by LukeTheJoker, on Flickr
A little hot melt glue...

DSC00147 by LukeTheJoker, on Flickr
Works well!

DSC00148 by LukeTheJoker, on Flickr

Although this worked for me, a dremel type tool would be much safer, and probably do a neater job, but it can be done!

Luke.

 

[kim_dude]

What type of battery source for that Luke?

 

[LukeTheJoker]

What type of battery source for that Luke?

Still have not used it, good chance it will be on this years big build off bike though.
The donor light ran on 3xAAA batteries in series, so requires around 4.5V, thinking about setting it up with a battery pack that runs 4xAA batteries like this hidden in the frame or the big headlight housing:

I have an over-abundance of high quality rechargeable AA batteries since the death of my old camera, the new one takes a moulded battery pack...

Luke.

 

[us56456712]

Score it with a glass cutter, wrap a cotton string around the score, soak the string in lighter fluid and light it off. Should crank and fall apart at the score.