Sam Thompson Posted June 27, 2009 Share Posted June 27, 2009 I'm just about to throw away about a dozen old cinema arc- lamps. They have a tungsten anode, a cylinder 1''h X 5/8''w. Does anyone have any idea if this stuff is workable and how? I'm hoping that I can weld a handle on and forge it. Quote Link to comment Share on other sites More sharing options...
Thomas Dean Posted June 27, 2009 Share Posted June 27, 2009 (edited) I don't believe you can weld tungsten, it is used in the welding field as the electrode in GTAW/TIG welding process==Gas Tungsten Arc Welding/Tungsten Inert Gas. BUT don't throw it away...IIRC, Hofi has used the stuff for drifts. Albert Habermann, as the MasterSmith, and Hofi along with some of Hofi's folks, slit and drifted 4" solid and passed 4" solid through the hole several years ago. They used tungsten as the drifts and maybe as the slitter also, not sure about that, but tungsten was used on this project. I saw a video of this when I took my class at Tom Clark's several years back. I believe the tungsten was from spent mortar rounds that Hofi got in Isreal. I think it would shatter if you tried to forge it, especially it being that small. Tungsten will break, does not bend. Edited June 27, 2009 by Thomas Dean Quote Link to comment Share on other sites More sharing options...
ichudov Posted June 27, 2009 Share Posted June 27, 2009 I don't believe you can weld tungsten, it is used in the welding field as the electrode in GTAW/TIG welding process==Gas Tungsten Arc Welding/Tungsten Inert Gas. Tungsten is hard to weld, but it is weldable. I have in my garage several tungsten filler rods that can be used to weld tungsten with TIG. And yes, you would also use tungsten electrodes to make the arc. The filler rod is not the same as the electrode. The difficulties of welding tungsten are twofold: first, it has a very high melting point, and second, it quickly oxidizes in open air, so it needs a inert atmosphere to prevent oxidation. Quote Link to comment Share on other sites More sharing options...
Thomas Dean Posted June 27, 2009 Share Posted June 27, 2009 It would seem that the tungsten electrode would melt when you got the tungsten you are welding hot enough to weld. I have said it before and will continue to say it..."I woke up this morning at the perfect age to learn something new." I would love to see it done! Do you have some pics of tungsten that has been welded? I will have to check into this... Quote Link to comment Share on other sites More sharing options...
Hofi Posted June 27, 2009 Share Posted June 27, 2009 Sam you can not weld tungsten you can braze the tungsten with silver rod. and you can not forge it .The tungsten will shutter !!! be carfull !!!!!!!!! All my tools are ''HOT FIT'' AND IF YOU DO IT YOU MUST TAKE UNDER CONSIDERATION THAT THE EXPANTION/SHRINK FACTOR IS DIFFERENT THEN THE MANDREL YOU PUT ON!! The whole system is explained on -hofi 1013 BP- I attuch more tooling that I made the last half a year. Before you start you must check if the tungsten you have is hard or soft with a file if it is the hard one you can do nothing only the soft one you can file or grind or cut on the lathe. Thomas Dean the name is ALFRED and not ALBERT. The attuched 4'' round in 4''round is the one I made in my smithy and I still have it with me while Habermman was in my smithy and I showed him the slitting possibility with the tungsten whice he never new about it before HOFI Quote Link to comment Share on other sites More sharing options...
John Larson Posted June 27, 2009 Share Posted June 27, 2009 Hofi told us at a hammer in that he didn't forge his tungsten drifts, but rather abrasively machined them to shape. He said the armor piercing shells can be found on the desert floor. Quote Link to comment Share on other sites More sharing options...
Hofi Posted June 27, 2009 Share Posted June 27, 2009 Forgot to send tis foto's Hofi Quote Link to comment Share on other sites More sharing options...
Thomas Dean Posted June 28, 2009 Share Posted June 28, 2009 .... Thomas Dean the name is ALFRED and not ALBERT. .... Yes, my bad, my fingers got away with me! Also, I think the tungsten ichudov may be referring to is Tungsten Carbide, that you can TIG, as applying it to saw blade teeth for an example. Not quite the same stuff as what is coming out of the lamps that Sam has. Quote Link to comment Share on other sites More sharing options...
Thomas Dean Posted June 28, 2009 Share Posted June 28, 2009 That slit and drift job is Beautiful work Hofi, and MOST impressive! Thanks for the pics. Quote Link to comment Share on other sites More sharing options...
mcostello Posted June 28, 2009 Share Posted June 28, 2009 Scrap price will probably scare you, if you are going to throw them away, toss here, we will work out the details later. Quote Link to comment Share on other sites More sharing options...
JeremyP Posted June 28, 2009 Share Posted June 28, 2009 Yes, my bad, my fingers got away with me! Also, I think the tungsten ichudov may be referring to is Tungsten Carbide, that you can TIG, as applying it to saw blade teeth for an example. Not quite the same stuff as what is coming out of the lamps that Sam has. I dont believe so. I've only seen tungsten carbide being brazed on to the tool base. Quote Link to comment Share on other sites More sharing options...
Hofi Posted June 28, 2009 Share Posted June 28, 2009 I dont believe so. I've only seen tungsten carbide being brazed on to the tool base. __________________ Freelance Fabber is right as I said on the thread befor the TUNGSTEN CARBIDE can be brazed only !! brazing= glue . Hofi Quote Link to comment Share on other sites More sharing options...
sloscheider Posted June 29, 2009 Share Posted June 29, 2009 You may already know this but if the bulbs are still intact BE VERY CAREFUL WITH THEM - they are high pressure bulbs (I believe it's filled with Xenon) and the glass is optically pure so it won't show up on an x-ray meaning they'll have to find the glass by you telling them where it hurts.... I was next to a lamp house when the bulb exploded upon startup - this was a 5,000 watt bulb and sounded like a shotgun! It completely shattered the large mirror behind it. When we changed the bulbs we wore a full face shield and a chest protector. Quote Link to comment Share on other sites More sharing options...
Sam Thompson Posted June 29, 2009 Author Share Posted June 29, 2009 Yes thanks... I did know that. The way to do it is encase them in their shields and boxes and tap the end of one of the electrodes, it breaks the seal and the glass can be safely broken. I gather that the tungsten is also slightly radioactive. Quote Link to comment Share on other sites More sharing options...
CBrann Posted June 29, 2009 Share Posted June 29, 2009 Sam, Are the arc lamos in question 5 year sold 10 year sold? older..? It might just be better to dispose of them properly. Some older lamps may have mercury vapor in them, or other stuff, If you don't know, then proper disposal might be the order of the day. I am not sure what kind of lamps you have, are they single or dual envelope? As far as I know tungsten is not radioactive, but thorium gets added to TIG rods to make them strike better. Those rods are only slightly radioactive (ie not harmful, but detectable levels) To my understanding from a long conversation here recently. Quote Link to comment Share on other sites More sharing options...
Sam Thompson Posted June 30, 2009 Author Share Posted June 30, 2009 I'm told that the radioactivity is induced by thousands of hours of arcs. Proper disposal involves breaking the seals so I assume that whatever is inside is harmless. Quote Link to comment Share on other sites More sharing options...
CBrann Posted June 30, 2009 Share Posted June 30, 2009 Sam, there are so many different varieties of lamps, and disposal procedures, I just tend to be wary. If disposal procedure says to break the envelope, go with it. I have seen high temp high pressure sodium vapor lamps hand grenade (kaboom! ugly ugly stuff) and I know that mercury vapor is the best way to get mercury poisoning. Also there tends to be lots of "rare earth" elements in some types. Once in a while I look at stuff and say that cool whatever it is, only to say that "what is it? " If i don't know then it stays wherever it is. I heard a story of a guy that worked at Pratt and Whitney, that used a jet engine part to stir his coffee. Turns out it was an exotic radioactive alloy, that basically poisoned him. And he never knew. The building as doing a "WMD" excercise and he registered high with a geiger counter. Left in an ambulance. Quote Link to comment Share on other sites More sharing options...
Sam Thompson Posted July 1, 2009 Author Share Posted July 1, 2009 I was thinking of an air rifle from a distance... fun and educational! So, what it boils down to is: It can be ground but not forged, brazed but not welded and has a high scrap value. Quote Link to comment Share on other sites More sharing options...
David E. Posted July 2, 2009 Share Posted July 2, 2009 I was thinking of an air rifle from a distance... fun and educational! So, what it boils down to is: It can be ground but not forged, brazed but not welded and has a high scrap value. Sam, I get TC nozzles made for the grit blasters I make, they are workable until they get sintered, then it is as everyone has said above, They can be broken down and recycled into a lower grade. I can ask my supplier for you if you want. The nozzles I have shatter very easily but last ages. David. Quote Link to comment Share on other sites More sharing options...
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