Wildalaska
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Keep in mind that the MIM parts Kimber uses probably costs them, after mold amortization, about .05 each...
WildsohowcometheyaresoexpensiveAlaska
WildsohowcometheyaresoexpensiveAlaska
My E-mail to Kimber and their reply Regarding the MIM parts in my TLE II
- Thread starter Master Blaster
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Master Blaster
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Alot of pseudo science gets tossed around when ever there is a mention of MIM parts.
For example the issue of density is irrelevant as presented.
Here is why: Density = mass / volume
Lead has a higher density Grams per CM3 than steel, but no one will argue I hope, that the higher density of lead makes it an appropriate material for a slide stop.
So the statement that a MIM part is 98% as dense as a forged part is basically meaningless, unless the chemical formulation of the steel is identical, the ductility and the hardness are also identical, and the thickness, and width of the part is identical.
A cast lead part has 200% of the density of a forged steel part but is obviously not as strong by any stretch of the imagination.
I have a 1999 Kimber that I have put 7,000 + rounds through with no part failures. My newer TLE II has about 1500+ - rounds through it as well.
It does seem that the newer guns have more failures, which is a quality control issue, the magnitude of which I am attempting to gauge.
As far as the MIM proccess goes I thought that baking the part in a vacum furnace removed the binder and took care of any voids.?????
The broken slide stop which I saw on line broke at the thinnest area. Remington has a excellent information area on MIM which is used in all of their rifles for various parts. They mention that there is an acceptable ratio of thickness to length and stress, after which MIM will fail. The slide stop seems to be pushing that ratio as far as I can tell.
For example the issue of density is irrelevant as presented.
Here is why: Density = mass / volume
Lead has a higher density Grams per CM3 than steel, but no one will argue I hope, that the higher density of lead makes it an appropriate material for a slide stop.
So the statement that a MIM part is 98% as dense as a forged part is basically meaningless, unless the chemical formulation of the steel is identical, the ductility and the hardness are also identical, and the thickness, and width of the part is identical.
A cast lead part has 200% of the density of a forged steel part but is obviously not as strong by any stretch of the imagination.
I have a 1999 Kimber that I have put 7,000 + rounds through with no part failures. My newer TLE II has about 1500+ - rounds through it as well.
It does seem that the newer guns have more failures, which is a quality control issue, the magnitude of which I am attempting to gauge.
As far as the MIM proccess goes I thought that baking the part in a vacum furnace removed the binder and took care of any voids.?????
The broken slide stop which I saw on line broke at the thinnest area. Remington has a excellent information area on MIM which is used in all of their rifles for various parts. They mention that there is an acceptable ratio of thickness to length and stress, after which MIM will fail. The slide stop seems to be pushing that ratio as far as I can tell.
Zircon, I'm glad to see another metallurgist here ! ....MIM is a newer development to Powder Metal parts .PM has been used for years in the gun business Remington has made it for at least 40 years for the gun industry and others . They specialized in high density parts , approaching 100% density. The comment about 60-80% density may be referring to PM where low density parts are made for filters and pre-lubricated bushings etc. Dan Wesson was ,I think , the first gun company to use PM extensively...... MIM is just another fabricating method . Proper design, proper choice of material ,proper heat treating and proper quality control are all necessary regardless of the fabricating method. QC is not an easy job , it is a job for everyone and it's a constant job to ensure that good quality is maintained . While some blame companies for wanting higher profits , how many shooters are willing to buy an expensive gun ? People have told me I'm stupid , crazy, a fool etc for buying an expensive HK P7, but it still works after many years and lots of use .
Sean Smith
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MIM
sear
mag catch
disconector
plunger tube
CAST
safety lock
grip safety
FORGED
slide
receiver
barrel
slide stop
MACHINED from bar stock
hammer
all pins
bbl link
bbl bushing
trigger fingure piece
ejector
firing pin
firing pin stop
extractor
http://www.1911forum.com/forums/showthread.php?t=62993
You want a pistol that has no MIM, get a Wilson Combat. Of course it's more expensive...
The going price for a Springfield Loaded seems to be around $650.
The going price for a Kimber Custom II seems to be around $600.
Seems like about the same price to me...
TLEs go for around $660 on Gunbroker. Once you pay shipping and FFL, it's about $700.
So much more expensive than what?
The going price for a Springfield Loaded seems to be around $650.
The going price for a Kimber Custom II seems to be around $600.
Seems like about the same price to me...
TLEs go for around $660 on Gunbroker. Once you pay shipping and FFL, it's about $700.
Actually, I had Springfield in mind. Colts go for $200+ more than a comparably-equipped Springer here in California, but maybe that's just HERE. I never considered Kimber because, well, the name sounds sorta pansy to me.
But that's just me.
Daniel T
Member
Well, the NRM 1991s are going for around $600, so I guess you're not paying that much more for them.
...
Thanks Sean.
spacemanspiff
Senior Member
replacing the MIM parts is no biggie...if you spread it out over time the cost is minimal. spend $50-75 a month on them and have your favorite smith make sure they are installed correctly. so far i've replaced the slide stop, firing pin stop, bushing, and recoil spring. next up is going to be the MSH, the mainspring, sear and hammer. after that its the grip safety, and i'm thinking about a new barrel.
after that, i'm still pondering whether i want to get another kimber, or just get a sig 1911 that has no mim part. the cost would be comparative after replacing all MIM on the kimber.
after that, i'm still pondering whether i want to get another kimber, or just get a sig 1911 that has no mim part. the cost would be comparative after replacing all MIM on the kimber.
What I don't read about is MIM parts breaking in Springfields and Colts.
I also don't read about MIM hammer and sears breaking either...in any brand. Or I just missed it and there is some breakage.
Is that because most people never shoot enough rounds through one gun to "test" the durability of MIM parts or the people that do shoot a lot of rounds "pitch" the MIM parts for better parts soon after they buy the gun?
Don't know.
I also don't read about MIM hammer and sears breaking either...in any brand. Or I just missed it and there is some breakage.
Is that because most people never shoot enough rounds through one gun to "test" the durability of MIM parts or the people that do shoot a lot of rounds "pitch" the MIM parts for better parts soon after they buy the gun?
Don't know.
The Sig has no MIM parts, but makes up for it in cast parts. They also haven't been receiving stellar reviews either. They seem to function, but some people have been nitpicking them to death. For the price they should be better, but almost any new 1911 on the market will sell.
cerberus
member
Name sounds "Pansy"
QUOTE= by RileyMc
"I never considered Kimber because, well, the name sounds sorta pansy to me.
But that's just me."
Thanks for the laugh.
QUOTE= by RileyMc
"I never considered Kimber because, well, the name sounds sorta pansy to me.
But that's just me."
Thanks for the laugh.
Master Blaster, I think maybe you're taking the density term out of context. Density is in fact a critical attribute for MIM and cast parts. It's true you can't compare a part made of lead (with high density) with a part made from titanium (relatively low density) and assume that the lead part is stronger because it has a higher density. 'Taint ever gonna happen.
However, if a steel part is supposed to have a theoretical density of 7.9 grams/cc and it only has a density of 7.8 grams/cc, or 98.7% of theoretical, what do you suppose happened to the other 0.1 gram/cc? It's likely taken up by void volume within the part. So, when we speak of density in terms of a percentage of theoretical, it is a very important number. Fully dense parts do not contain voids. Voids help nucleate cracks under repeated loading. This is a well known fact, and there are literally tens of thousands of pages referring to this phenomenon in the metallurgical/scientific literature.
The high temperature sintering does not always eliminate the voids, and in fact there is almost always some small void fraction in parts consolidated from powders at high temperatures. Densification occurs because the the voids contain surface area. This surface area within an otherwise solid mass creates additional "energy" (in a thermodynamic sense) within the part. The part wants to get to a state of lowest energy and it does this by eliminating the surface area. However as the surface area is eliminated, so is the driving force to eliminate it, and eventually there is a point of diminishing return.
In order to achieve 100% density one fix is to hot isostatically press the part. This imparts additional work or "energy" on the part to supplement the pore surface area reduction process. HIPing utilizes high temperatures, 1600 - 1700F, and very high pressures of gas external to the part, 30,000 psi or so, to literally collapse the porosity and squeeze it out of the part. Because this is a batch process that takes a day or so to complete, it is necessarily expensive.
Where MIM seems to fail in using it on a 1911, is that the part geometry, shape and size is already set in concrete. There is little allowance for porosity within some of the more highly loaded 1911 parts. If a pistol was being designed from scratch, the MIM part could be increased in size by 3 or 4% and it would function just fine - even with small amounts of porosity because the mechanical loads transmitted to the part would be supported by a larger crossectional area, and internal stresses in the part would be low enough to preclude crack initiation and growth.
I hope this helps you understand a fairly complex process.
Zirc
However, if a steel part is supposed to have a theoretical density of 7.9 grams/cc and it only has a density of 7.8 grams/cc, or 98.7% of theoretical, what do you suppose happened to the other 0.1 gram/cc? It's likely taken up by void volume within the part. So, when we speak of density in terms of a percentage of theoretical, it is a very important number. Fully dense parts do not contain voids. Voids help nucleate cracks under repeated loading. This is a well known fact, and there are literally tens of thousands of pages referring to this phenomenon in the metallurgical/scientific literature.
The high temperature sintering does not always eliminate the voids, and in fact there is almost always some small void fraction in parts consolidated from powders at high temperatures. Densification occurs because the the voids contain surface area. This surface area within an otherwise solid mass creates additional "energy" (in a thermodynamic sense) within the part. The part wants to get to a state of lowest energy and it does this by eliminating the surface area. However as the surface area is eliminated, so is the driving force to eliminate it, and eventually there is a point of diminishing return.
In order to achieve 100% density one fix is to hot isostatically press the part. This imparts additional work or "energy" on the part to supplement the pore surface area reduction process. HIPing utilizes high temperatures, 1600 - 1700F, and very high pressures of gas external to the part, 30,000 psi or so, to literally collapse the porosity and squeeze it out of the part. Because this is a batch process that takes a day or so to complete, it is necessarily expensive.
Where MIM seems to fail in using it on a 1911, is that the part geometry, shape and size is already set in concrete. There is little allowance for porosity within some of the more highly loaded 1911 parts. If a pistol was being designed from scratch, the MIM part could be increased in size by 3 or 4% and it would function just fine - even with small amounts of porosity because the mechanical loads transmitted to the part would be supported by a larger crossectional area, and internal stresses in the part would be low enough to preclude crack initiation and growth.
I hope this helps you understand a fairly complex process.
Zirc
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Master Blaster
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Thanks Zircon, How does the formulation of the alloy affect the strength of the MIM "steel" part? is there a standard formulation for stainless and for carbon steel that is used in MIM??????
I know in knife making different alloys and small percentages of trace elements affect the ductility and the hardness, wear resistance, and other properties.
Does the same hold true for mim?
What about the heat treating??? Since Harder is not always a good thing for a part since if it is too hard it becomes brittle.
It would be interesting to test Kimbers mim against Colt and Smith and Wesson's
Lastly at one time I heard that Chip McCormick made the small parts for Kimber and many of the other 1911 manufacturers including some of the customs anyone have any idea if this is still true???
Thanks
I know in knife making different alloys and small percentages of trace elements affect the ductility and the hardness, wear resistance, and other properties.
Does the same hold true for mim?
What about the heat treating??? Since Harder is not always a good thing for a part since if it is too hard it becomes brittle.
It would be interesting to test Kimbers mim against Colt and Smith and Wesson's
Lastly at one time I heard that Chip McCormick made the small parts for Kimber and many of the other 1911 manufacturers including some of the customs anyone have any idea if this is still true???
Thanks
Yes, all the usual suspects apply for finished attributes of the steel. Chemical composition is very important for hardness, strength, and toughness, as is the heat treating recipe. I honestly have no idea what composition Kimber or others specify for their metal powders. At one time on the 1911 forum I offered to do a failure analysis on a broken part, but no one took me up on it. The failure analysis can identify composition, hardness (and from that infer the mechanical strength), and the failure mode (i.e., did the part fail from gross overload, from fatigue, or from any number of other mechanisms.)
Zirc
Zirc
JohnBT
Member
"When Jack Warne was a baby, his family moved to the town of Kimba [Australia], which is pronounced "Kimber." It is an aboriginal word meaning "brush fire""
Copied from an article in Field & Stream
_______________
Aren't most of the Springfield slides and frames still made in Brazil? That should save them a few $$ compared to the homegrown Colts and Kimbers.
JT
Copied from an article in Field & Stream
_______________
Aren't most of the Springfield slides and frames still made in Brazil? That should save them a few $$ compared to the homegrown Colts and Kimbers.
JT
I believe that list from Kimber is a partial list of the MIM parts in their guns. I'd poke around on the 1911 forum for the complete list. I have seen more part breakage from Kimber MIM parts than others - it could be that they're selling a lot more pistols than any of the other makers and that statiscally the parts breaking is the same across the industry.
My Kimber GM is about 6 years old and nothing has broken on it.
Someone suggested a Wilson to avoid MIM parts - Wilson stopped using MIM parts in their pistols about a year ago.
From: Nicholas Moraitis [mailto:[email protected]]
Sent: Thursday, June 24, 2004 9:27 AM
To: 'Wilson Combat Info'
Subject: RE: Product Question
Over a year ago we started using Bullet Proof parts on all our pistols, even the CQB and KZ.
Thank you
Baer does not use any MIM parts in their guns. Rock River might not use MIM (it's hard to know what they're using) unless it's a customer supplied part.
Wildalaska
member
My understanding is the Kimber mim is done in Israel.
Wildandiwasntkiddingabout.05eachAlaska
Wildandiwasntkiddingabout.05eachAlaska
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Master Blaster
Member
Here is BUL's site, I read that they are now Kimber's part supplier for the MIM parts as welll as the frames for the polymer 1911.
The guide rod looks just like the one in a Kimber but that does not mean anything since mine appears to be machined.
http://www.bultransmark.com/index2.htm
The thing that makes me wonder if this is true is the fact that when I went to BUL's site, there is no link to or mention of Kimber at all.
They do mention that they are making polymer frame s for Springfield!!
The guide rod looks just like the one in a Kimber but that does not mean anything since mine appears to be machined.
http://www.bultransmark.com/index2.htm
The thing that makes me wonder if this is true is the fact that when I went to BUL's site, there is no link to or mention of Kimber at all.
They do mention that they are making polymer frame s for Springfield!!
bountyhunter
member
It is technically correct but misleading. It means basically that the final part is about 98% as dense as a forged part. It does not mean the failure rate is the same.
Any part put in a mold (cast or MIM) has the potential for a casting viod (air gap) in the mix which results ina weak spot. The thinner the piece, the more likely the part is to fail if such a defect is present.
MIM parts are subject to a second defect when the metal powder particles are not uniform in size or the slurry (polymer/powder mix) is not completely mixed. It will make "lumps" in the metal which are different density and can fail there.
A MIM part properly made is an excellent part. Unfortunately, I have seen many which looked awful and not just Kimbers. The SW hammers and triggers are very inconsistent in finish. Another upside to a forged/machined part is that if it has an internal defect, the stress of grinding on it will probably break it before it gets used. An MIM part goes straight from the oven to the gun. X-ray would show the defects, but obviously that would be too expensve. IMO, long thin pieces are not good candidates for MIM production parts because the quality control is not there.
Am I the only one who noticed that the person from Kimber who wrote the email response was an "MBA" (Masters in Business Administration = bean counter) not an engineer? Doesn't mean the info is wrong, but the source is likely not an expert in anything but cost control.
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