Hi all! This is my first post on the Miller forum.
I use my Econotig for general hobby welding, and I occasionally use it for my X-ray repair business. One problem that I recently encountered is I was trying to repair a broken metal bracket that holds a rear cover onto a Dental X-ray tube head. From the look and feel of the metal, I was certain that it was cast Aluminum, but I had a heck of a time trying to Tig weld it. The broken section of the bracket is only about 0.25 in wide by 0.125 in think, and about 3 inches long. The metal seems to be very brittle, as it breaks very easily when flexed even a small amount. When trying to Tig weld it, the metal just melts into a very rough looking blob, and will not accept Aluminum filler rod. After many frustrating attempts, I began to wonder if maybe the metal isn't Aluminum, and is rather Magnesium. So, could anyone please tell me how I could test the metal to determine if in fact it is Magnesium instead of Aluminum? BTW - I'm using pure Argon, with 1/16 inch Thoriated Tungsten.
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Thread: Aluminum or Magnesium?
01-13-2008, 06:30 PM #1
Aluminum or Magnesium?Some people are like a Slinky... They aren't much good for anything, but they bring a smile to your face when you shove them down a flight of stairs.
01-13-2008, 07:23 PM #2
Unless you are welding in a vacum chamber that has been purged, welding magnesium would cause it to burn, and boy does it ever burn. (I guess grade 9 science was good for something after all. )Dynasty 200DX, first generationMakita 5" grinder
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01-13-2008, 08:03 PM #3Ken
What else is there besides welding and riding. Besides that
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01-13-2008, 08:34 PM #4Some people are like a Slinky... They aren't much good for anything, but they bring a smile to your face when you shove them down a flight of stairs.
01-13-2008, 08:07 PM #5Some people are like a Slinky... They aren't much good for anything, but they bring a smile to your face when you shove them down a flight of stairs.
01-13-2008, 08:17 PM #6
09-30-2008, 09:28 AM #7Junior Member
- Join Date
- Feb 2006
The filler rod is expensive (last purchase $92/Lb.) but a pound goes a long way! Trick is to find a supplier willing to sell less than 10 Lbs!
I saved all the shavings from turning a repair (lathe swarf) in a paper bag and threw it on a bonfire. VERY bright white, but quickly burnt itself out. Don't try that in your shop! So yes, keep the area clean from shavings and grinding dust.
Magnesium oxidizes very quickly, so any repairs need to be cleaned back to bare metal. I usually use a carbide "tree" in a die-grinder for this. It helps to direct the chips away from your clothing.Randy Forbes
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09-30-2008, 10:36 AM #8
I appreciate everyone's comments, but I'm still waiting for an answer to my question of how to dertermine what type of metal I have. I suppose I could shave off a few splinters of metal with a knife, and then try to burn it with a propane torch. If it glows very brightly while burning, then it probably is magnesium. Does anyone know of another way to test metals in order to determine what they are? I know with various grades of steel you could determine a lot about their makeup with a spark test by grinding them and seeing the color, brightness, and types of sparks that fly off. That basically shows how much carbon is in the steel. But what about testing Aluminum? Is there a simple test that can help you determine the type of Aluminum that you are about to weld?
09-30-2008, 08:49 PM #9Senior Member
- Join Date
- Dec 2007
Magnesium vs aluminum
You have picked a good quick method to test for magnesium with the shavings test. The camping stores have magnesium fire starters for just this use.
This should separate magnesium from alum.
I don't know of a valid method of determining the exact alloy type except thru the use of a Niton xray gun. This is very expensive equipment and I have nobody near me who has one.
I can offer this: if you determine your alloy is magnesium, I have a 3/8" thick plate of mg AZ31B. I will slice a piece off for you to try to tig weld if this helps.
If your piece is alum, it may be easier to find the proper tig alloy.
I defer to others on this forum for their expertise.
good luckThermal Arc GTSW400, Airco Heliwelder II, Miller Dynasty 350, Hypertherm 1000, oxy-fuel setup, metal cutting bandsaw, air compressor, drill press, etc.:
Call me the "Clouseau" of welding !
01-13-2008, 07:24 PM #10Senior Member
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- Oct 2007
- gate city virgina
I believe you may want to consider some other kind of tungsten since i have heard this type is very harmful to your health without proper ventalation.