Dear Friends,
Very often in these missives, I've read statements referring to MIM (metal injection molded) parts as the metalurgical equivalent of poison ivy. I find it quite curious.
My personal background is a foundry/engineering history. Yeah, I know the difference between mallable iron and grey iron, and the difference between 4140 steel and cheap pot metal. I understand the work hardening achieved through forging as opposed to the lack of it in a casting.
Machine shop time is very expensive. The reason MIM is used is that you get a high quality part, almost perfectly to spec, right out of the mold. The initial set up cost is fairly expensive, but once you're set up, you can produce a large number of parts quite cheaply. The amount of machine shop work required is very minimal.
Is a MIM part as strong as the same part crafted out of fine tool steel? Nope. The strength is about 97%. Geez, this means that instead of having a part thats 300% stronger than it needs to be, you have a part thats only 291% stronger than it needs to be. Who the hell cares? We're dealing with handguns here guys, not Formula One racecar engines. We don't have any parts rotating 14,000 times a minute.
There's nothing wrong with crafting a tool (handgun) out of the absolutely finest material available. There's also nothing wrong with crafting a tool out of material that's adequate for the job. One last example, Caspian cast (not forged, not tool steel) frames---did you ever see one break?
Best Wishes, Mark Shuell.
Very often in these missives, I've read statements referring to MIM (metal injection molded) parts as the metalurgical equivalent of poison ivy. I find it quite curious.
My personal background is a foundry/engineering history. Yeah, I know the difference between mallable iron and grey iron, and the difference between 4140 steel and cheap pot metal. I understand the work hardening achieved through forging as opposed to the lack of it in a casting.
Machine shop time is very expensive. The reason MIM is used is that you get a high quality part, almost perfectly to spec, right out of the mold. The initial set up cost is fairly expensive, but once you're set up, you can produce a large number of parts quite cheaply. The amount of machine shop work required is very minimal.
Is a MIM part as strong as the same part crafted out of fine tool steel? Nope. The strength is about 97%. Geez, this means that instead of having a part thats 300% stronger than it needs to be, you have a part thats only 291% stronger than it needs to be. Who the hell cares? We're dealing with handguns here guys, not Formula One racecar engines. We don't have any parts rotating 14,000 times a minute.
There's nothing wrong with crafting a tool (handgun) out of the absolutely finest material available. There's also nothing wrong with crafting a tool out of material that's adequate for the job. One last example, Caspian cast (not forged, not tool steel) frames---did you ever see one break?
Best Wishes, Mark Shuell.