Mad Madam MIM

Daymaker

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Remember her???:D
I tried a search but came up wanting. Just what does "MIM" mean? I'm currently waiting to pick up a Model 629-5, 61/2" bbl., Classic. I saw the sticky re: whining, etc., and found there are MIM haters. Why? Is the quality of a MIM part less than whatever was the "normal"? Is MIM cosmetic? Is it "fragile"? Does it affect accuracy? Does it reduce reliability? If so, can it be swapped out for an "original" part?
 
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Metal Injection Molding (MIM) is a modern manufacturing technique for producing metal parts that are more uniform in shape and finish than cast or forged, and generally require less machining.
They are used as original parts on many products, ranging from NASA machines to S&W revolvers.
 
I have a -5 629, and honestly, I cannot tell ANY difference in quality, trigger pull, etc from my -4 625 or my 610.
Yes in doesn't have the "Forged by Thor" parts but for I doubt that if you blindfolded all the MIM haters and gave them the gun, 99.9% couldn't tell the difference.
Your target isn't going to know the difference between MIM and Forged.
I will edit this with one caveat to the forged part group. I will give them the fact that there most likely is a difference in the pre war guns that where essentially almost hand fitted custom guns.
 
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Howdy and welcome to the forum.

MIM is fine, just not preferred by many. Same goes with internal locks.

I have had to send two new S&W's back to customer service this year, one of them twice, and it had nothing to do with MIM. Your more likely to have an issue with final assembly carelessness, than parts durability or fit.
 
Even the honest MIM lovers will admit that forged parts are strength wise stronger than MIMs, but we admit that MIMs parts are easier for the less skilled assemblers to fit. You pays your money and makes your choice.
 
Okay. So what's to hate???
Nothing to hate, unless you just want to. It's just what is made now. If you want new, it's what you get. If something breaks, they fix it free. If you want the other, it's not new. If you don't already have a preference, you will not give it a second thought. If they were awful, there would be a thriving third-party market of forged replacements. There isn't.

Kind of like me desiring my favorite car, the 1965 Buick Riviera GS. I could find one, but my skills would not make me comfortable buying one. If they made a new one, I'd get it, but they don't, so there is some other new car in the driveway.
 
Well, I don't see the difference. Looking around on other sites I read that my 915, bought new in 1992, is chock full of MIM. But boy does it shoot nice and straight. You can plink at things 100yds. away and hit within a 12" circle. MIM or no MIM, I'm sure I'll have a blast with my new (to me) 629. Thanks gentlemen.
 
I lube the MIM parts with moly and forget about it.
The steel frames are still forged.
Ruger was a leader in doing this.

But my new M58 & M57 both bought days apart had two different feeling triggers. Moly fixed that.
 
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Even the honest MIM lovers will admit that forged parts are strength wise stronger than MIMs

The real question is: is that of any practical significance? The answer is no unless you're OCD and AR about such things. The difference in strength is only about 2% or so I've read. MIM parts can be made from an almost endless array of carbon and stainless steel alloys and are easily heat treated thru and thru-not just case hardened. My only beef with them is that they sometimes look like hell comparatively so it does sometimes make a difference on external parts. There is no problem with their utility however.

Bruce
 
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MIM is the cheapest and lowest quality way to create parts. Read Jerry Kuhnhausen's "The Smith and Wesson Revolvers - A Shop Manual", and he lays it all out. It is MUCH lower quality than the investment castings that Ruger and others use. Sorry, but if it walks like a duck, and quacks like a duck, it's a duck.

Don
 
MIM is the cheapest and lowest quality way to create parts. Read Jerry Kuhnhausen's "The Smith and Wesson Revolvers - A Shop Manual", and he lays it all out. It is MUCH lower quality than the investment castings that Ruger and others use. Sorry, but if it walks like a duck, and quacks like a duck, it's a duck.

Don
This is factually incorrect. MIM is more expensive to stand up; the savings is long run in volume and uniformity. The quality is evident by the industries -- like aerospace -- that use it in critical functions.

MIM, forged or cast compete evenly in most applications, provided they're made correctly; any is the lesser if the process isn't properly performed.
 
S&W could, no doubt, on a very limited basis, build guns the same way they were build in the "good old days". I say limited because they couldn't find enough employees with the necessary skills to build very many. The whiners would then be happy. Well, not real happy, because the guns would cost several thousand dollars each, and most of the whiners could then not afford the hand assembled, carefully fitted revolver of their dreams.
 
All I can say to MIM-apologists is: Take it up with the guy who wrote the book that everybody uses to work on Smith and Wessons with. That MIM parts are the lowest on the quality totem pole is a fact.

Don
There's no need to apologize for technology and hardware that is proven. I'll "take it up" with Mr. Kuhnhausen soonest. ;)
 
I agree that MIM parts suffice. But as with many other "upgrades," they all lead me to prefer to purchase older S&Ws without such improvements.
 
Everyone can argue the pros and cons on MIM parts and usually it's on a personal level that he or she's gun did or did not fail but statically this means very little. The truth is that manufacturers use MIM parts for one primary reason, to save money. Forget that marketing will spin it as 'New and Improved'. It's a rather unfortunate truth that most of today's manufacturers like automotive, appliances or guns are being run at the ground level by accounting. That this business model finds that the fastest and easiest way to increase profits is not by engineering and designing a better product or device but to cut the cost of the parts. Cost cutting of this type is a slippery slope and since it involves labor and QC it can easily erode the workforce's pride in workmanship and morale not to mention their numbers. You need not think too hard on this but it's not likely that a company will roll these cost savings into better wages, more QC or training.

My wife is a materials science engineer and we socialize with a number of metullurgists all from the aerospace world. The condensed argument, as I recall, for or against MIM parts really follows something like this. The process is not flawed and when done properly is very sound. That years ago a similar process was called Powder Metal and was used heavily in less demanding applications such as budget driven home owner and automotive parts. The powder metal parts had a bad reputation for failure for a bunch of reason I'm not sure of. That MIM parts are higher quality but for critical applications absolutely require a careful inspection or QC program that assures proper alloying, porosity/void detection, and heat treating. MIM designs must factor in the differences in density and strength and often this can alter dimensions. So I guess my question is do companies like S&W take their part savings and labor reduction and put it back into QC or pocket it ?
 
That MIM parts are higher quality but for critical applications absolutely require a careful inspection or QC program that assures proper alloying, porosity/void detection, and heat treating. MIM designs must factor in the differences in density and strength and often this can alter dimensions

My understanding of this statement is that MIM parts are not inferior but require high degrees of QC to make them suitable in critical applications. As far as re-engineering parts based on new material density and strength, that's sort of a restatement of the obvious. This also explains why many parts do not interchange between MIM and pre-MIM guns of the same frame size.

So I guess my question is do companies like S&W take their part savings and labor reduction and put it back into QC or pocket it ?

My feeling is that little goes back into quality control post assembly but rather into parts inspection & process development. As far as pocketing it, I believe it's more about maintaining a competitive price point for their product as much as anything else. Personally, I do believe that Smith & Wesson needs to pump a little more money into final inspection and QC plus tightening up the specifications for final product but that's a discussion for a different thread.

Bruce
 
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