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This may be a can of worms but I gotta ask.........


Cherokeewind

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In the metal injection molding process, the part is initially a mix of metal particles and plastic binder. When the formed part is sintered, the heat melts out all the plastic binder material and melts the metal particles together to form a solid part. The green part shrinks to 80% of it's original size as the binder burns off. What is left is a solid metal part. In the case of S&W lockworks, the parts are a heat treated metal that can be polished, welded, cut, or ground, the same as any other metal.

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3 hours ago, Toolguy said:

In the metal injection molding process, the part is initially a mix of metal particles and plastic binder. When the formed part is sintered, the heat melts out all the plastic binder material and melts the metal particles together to form a solid part. The green part shrinks to 80% of it's original size as the binder burns off. What is left is a solid metal part. In the case of S&W lockworks, the parts are a heat treated metal that can be polished, welded, cut, or ground, the same as any other metal.

Now that is interesting information.  

Question is the part within spec's once the binder burns off?  Or does it take considerable machining to reach that point?

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20 hours ago, alecmc said:

 

 

I dont know, Can you?

 

The point I was trying to make with my post is that the Performance center stamp doesn't matter, and I dont think that someone should buy a S&W based on that merit. 

 

If the gun happens to have the barrel and cylinder configurations they like and it just happens to be a PC gun... sure , buy it. But dont buy it just because it says PC on it.

 

 

 

Side note: 

I think 80% of my competition guns are pro series, probably cause they are the cheapest. As most as my guns are custom the first thing I'd do would be to rip it apart, replace the barrel, cylinder, and tune up the internals. 

I do agree with you,,, the trim line stamp isnt amounting to much, just the available features.

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15 minutes ago, pskys2 said:

Now that is interesting information.  

Question is the part within spec's once the binder burns off?  Or does it take considerable machining to reach that point?

The computer figures out how much bigger to make the mold so that the end product is exactly net size and shape when finished in most cases. Sometimes there is finish machining required, depending on the geometry of the part and what it is used for. The S&W parts don't require any 2nd operations.

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14 hours ago, Toolguy said:

The computer figures out how much bigger to make the mold so that the end product is exactly net size and shape when finished in most cases. Sometimes there is finish machining required, depending on the geometry of the part and what it is used for. The S&W parts don't require any 2nd operations.

 

And those S&W MIM parts are hard. I had to buy ceramic stones for them. 

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I may be remembering this incorrectly (I'm never wrong, incorrect yes but wrong.........never!!😇)

but someplace I think I read that the base alloy S&W uses for the MIM parts is harder than the core of the old forged case hardened parts.

 

Can any of you guys remember anything like that?

Edited by Cherokeewind
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2 hours ago, Cherokeewind said:

I may be remembering this incorrectly (I'm never wrong, incorrect yes but wrong.........never!!😇)

but someplace I think I read that the base alloy S&W uses for the MIM parts is harder than the core of the old forged case hardened parts.

 

Can any of you guys remember anything like that?

 

I'm trying to recall the exact MIM to forged comparison numbers, but I believe MIM was/is supposed to be around 95% the hardness of forged parts.

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51 minutes ago, Distant Thunder said:

 

I'm trying to recall the exact MIM to forged comparison numbers, but I believe MIM was/is supposed to be around 95% the hardness of forged parts.

95% of the density of traditional parts. Hardness is a function of the heat treatment.

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