S4 intake and cam cover materials
03-10-2008, 09:16 PM
#32
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I recently spent several hours stripping off the factory coating on an '88 S4 manifold. Both the intake and side plates were magnesium.
I'd like to see what a prototype intake looks like underneath . . . The production cast magnesium intake looks like an aorta from an alien species. I'm curious what compromises had to be made for production.
I'd like to see what a prototype intake looks like underneath . . . The production cast magnesium intake looks like an aorta from an alien species. I'm curious what compromises had to be made for production.
03-11-2008, 01:42 AM
#33
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FWIW, yes you can weld magnesium.
I have a welder bud that fixes vintage dirt bike engine cases all the time. He comes over to my shop as my TIG welder has a real pulser feature... a good 'ol tried and true Syncrowave !
A few weeks back he repaired a set of S4-GT valve covers for me where two of the corners had cracked off. Watching him work the mag was something. His efforts were both art and science. He tacked them on in a fashion that looked crooked. As he completed the welds, everything came into alignment and took just a little finishing of the welds. Once these get powder coated, no one would know.
The biggest pain, as Dennis mentioned, was stripping the factory paint / primer out of all the nooks and cranny's. Thomas' English Muffins have less... ;^)
I have a welder bud that fixes vintage dirt bike engine cases all the time. He comes over to my shop as my TIG welder has a real pulser feature... a good 'ol tried and true Syncrowave !
A few weeks back he repaired a set of S4-GT valve covers for me where two of the corners had cracked off. Watching him work the mag was something. His efforts were both art and science. He tacked them on in a fashion that looked crooked. As he completed the welds, everything came into alignment and took just a little finishing of the welds. Once these get powder coated, no one would know.
The biggest pain, as Dennis mentioned, was stripping the factory paint / primer out of all the nooks and cranny's. Thomas' English Muffins have less... ;^)
03-11-2008, 03:34 AM
#34
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How did you determine that? Didnt someone say that the side plates are aluminum?
also, how do you weld magnesium, if it can ignite and burn out of control?
can i scrap some of my intake with a file and ignite the filings with a butane torch?
Does mine look like aluminum both cover and intake? sure looks like the same material to me, as it looks and files like the earlier runner type cars. Or, are those magnesium too?
mk
also, how do you weld magnesium, if it can ignite and burn out of control?
can i scrap some of my intake with a file and ignite the filings with a butane torch?
Does mine look like aluminum both cover and intake? sure looks like the same material to me, as it looks and files like the earlier runner type cars. Or, are those magnesium too?
mk
I recently spent several hours stripping off the factory coating on an '88 S4 manifold. Both the intake and side plates were magnesium.
I'd like to see what a prototype intake looks like underneath . . . The production cast magnesium intake looks like an aorta from an alien species. I'm curious what compromises had to be made for production.
I'd like to see what a prototype intake looks like underneath . . . The production cast magnesium intake looks like an aorta from an alien species. I'm curious what compromises had to be made for production.
03-11-2008, 11:09 AM
#35
Nordschleife Master
Mark, if you take a file or a razor and try to light the shavings that will tell you if it is aluminum or mag.
You can weld mag even though it is flammible as the gas is inert and expels all air from the area, giving it nothing to be able to burn with. At least that is how I understand how you are able to weld it.
You can weld mag even though it is flammible as the gas is inert and expels all air from the area, giving it nothing to be able to burn with. At least that is how I understand how you are able to weld it.
03-11-2008, 01:14 PM
#36
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Mark:
Magnesium is welded using an inert gas process. For the work my friend did, he used my TIG (Tungsten Inert Gas) and does alter the gas flow parameters for the Mag. For the case and valve cover work, we used pure Argon as the gas.
Ignition of the Mag during welding is not a dangerous as folk lore suggests. Frankly, the mag dust from sanding on the welds to pretty things up is more dangerous.
What's interesting to watch is the oxydation of the mag after welding if the inert gas is taken away too early as the mag cools down. Basically, it turns black.
As far a telling a mag piece from aluminum, the simplest way is to weigh it and compared the weight to another one known to be mag. The Aluminum piece will be heavier. Other than this, there are some acid wipe tests where Aluminum will brighten and the mag will turn dark. I cannot recall of the top of my head which acid to use, but maybe someone else can recall this.
$0.02
Magnesium is welded using an inert gas process. For the work my friend did, he used my TIG (Tungsten Inert Gas) and does alter the gas flow parameters for the Mag. For the case and valve cover work, we used pure Argon as the gas.
Ignition of the Mag during welding is not a dangerous as folk lore suggests. Frankly, the mag dust from sanding on the welds to pretty things up is more dangerous.
What's interesting to watch is the oxydation of the mag after welding if the inert gas is taken away too early as the mag cools down. Basically, it turns black.
As far a telling a mag piece from aluminum, the simplest way is to weigh it and compared the weight to another one known to be mag. The Aluminum piece will be heavier. Other than this, there are some acid wipe tests where Aluminum will brighten and the mag will turn dark. I cannot recall of the top of my head which acid to use, but maybe someone else can recall this.
$0.02
03-11-2008, 08:03 PM
#38
Administrator - "Tyson"
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Take a picture with the side plates off
Some of the casting marks (if that's what they are) that other S4 intakes have are missing. So either this is different or they were ground off.
Some of the casting marks (if that's what they are) that other S4 intakes have are missing. So either this is different or they were ground off.
