macfixer01
Well-known member
This is another line of scrap I've gotten involved in recently, tungsten electrodes from xenon arc lamps. The local recycler pays $6.00 per pound for tungsten. This is the second batch I've sold, and probably half of these were from lower wattage (2KW) lamps. The total amount of metal in the two photos was from 79 lamps and weighed 33 pounds. I don't have pictures of it but the first batch I sold was approximately the same number of lamps except they were higher wattage (mostly 3KW-6KW) so that batch was 57 pounds. The stuff is incredibly dense though. To give you an idea of scale that cardboard box is only about 4 inches deep, and the rods are I'm guessing 3/16 inch and 5/16 inch in diameter and mostly around 2 to 4 inches long. The rods seem to be sintered so they're somewhat brittle, which worked out well since a hacksaw really wasn't much use on them. I just broke the rods off where they were encased in the glass since it doesn't come off them very easily.
If anyone is interested - On a new lamp the larger electrodes (Anodes) have a flat blunted end and those little balls and nodules you see growing on them are usually the result of excessive hours of use, hot-striking lamps before they cool down, or excessive AC ripple on the power supply. Those nodules cause the arc to jump around and create flickering and can cause the arc to flame out or be hard to strike in the first place. Similarly the pointed electrodes (Cathodes) come to a very sharp point on a new lamp but you see many here are somewhat blunted. A couple here got the tips broken off while breaking the lamps open, but most were just worn down from use and the metal redeposited onto the anodes and the glass. That wear increases the gap between the electrodes and can also make lamps hard to strike or prone to flaming out.
macfixer01
If anyone is interested - On a new lamp the larger electrodes (Anodes) have a flat blunted end and those little balls and nodules you see growing on them are usually the result of excessive hours of use, hot-striking lamps before they cool down, or excessive AC ripple on the power supply. Those nodules cause the arc to jump around and create flickering and can cause the arc to flame out or be hard to strike in the first place. Similarly the pointed electrodes (Cathodes) come to a very sharp point on a new lamp but you see many here are somewhat blunted. A couple here got the tips broken off while breaking the lamps open, but most were just worn down from use and the metal redeposited onto the anodes and the glass. That wear increases the gap between the electrodes and can also make lamps hard to strike or prone to flaming out.
macfixer01