What is "MIM?"


PDA






Topgun
May 8, 2004, 12:53 PM
Browsing Brownell catalog and see "MIM" is "metal injection molding."

Is that different from "sintered?"

Sez (among other gun parts) that the trigger on S&W is MIM. Mine sure doesn't LOOK sintered. Has machine marks and stuff.

Rifle parts, handgun parts, shotgun parts......all seem to have the MIM designation on the parts list.

Is this the same as "lost wax castings" that Ruger uses on everything?

If you enjoyed reading about "What is "MIM?"" here in TheHighRoad.org archive, you'll LOVE our community. Come join TheHighRoad.org today for the full version!
Selfdfenz
May 8, 2004, 01:40 PM
It's a discriptor for a certain kind of cast metal part and the technique for making them.

Some folks right here on THR have commented numerous times regarding negative experiences they had with various parts made via this method.

Make a pot of coffee, type MIM into the search box and relax reading for the rest of the afternoon. They have posted about all you would ever waht to know about MIM and more:p

TC and have a good one,
S-

RWK
May 8, 2004, 01:56 PM
Powdered metal parts.

otomik
May 8, 2004, 03:17 PM
IMHO
MIM parts are fine if the gun is designed with them in mind such as Rugers and Bersas. They're more brittle and will need a beefier design. They are not a good idea in 1911s and other designs not made with MIM parts in mind.

question: are titanium parts made with MIM processes?

Topgun
May 8, 2004, 03:37 PM
The S&W.....HAMMER is MIM. Jeez!

:eek:

mete
May 8, 2004, 04:58 PM
Powder metal or sintered metal is a process that has been around for many years and has many applications .Powdered metal is into a mold and compressed. The part is then heated to bond the powder particles ,that's called sintering. Density can vary greatly depending whether you want a filter(the least dense) a permanently lubed bushing, or a structural part.Even thirty years ago Remington made parts that through a double process approached properties of wrought material.Many metals can be used,they can be heat treated etc......MIM is a kind of second generation powdered metal. Metal powder is mixed with a polymer, it is injection moulded ,then it is heated which first drives off the polymer, continued heating sinters the powder. This process involves considerable shrinkage......There are many variables with either process .If the design of the part,application, alloy choice,heat treatment ,QC,etc are correct you will have a good part .If not you will have failures.

If you enjoyed reading about "What is "MIM?"" here in TheHighRoad.org archive, you'll LOVE our community. Come join TheHighRoad.org today for the full version!