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atv223
06-02-2011, 02:59 PM
Hello everyone, I am a brand new owner of a Kahr PM9 and very excited to have been turned onto this site from some members over at PAFOA.com! I have learned a ton already and glad I got here before I took my shiny new PM9 to the range for the first time.

In reading lots and lots of the site here, I see people talking a about spray cleaners and their impact on “polymers”. Since I have some experience in this area, I thought I would jump in here and clear up a couple of things.

First, people seem to be refereeing to polymers as if they are a single material and are all affected the same way by the same chemicals. As an analogy, it would be like referring to “Metal”, and thinking titanium, tin and steel all react the same way to chemicals and the environment.

Polymers are a very broad class of materials with extremely different physical and chemical properties. Everything from latex gloves, to car tires to Kevlar, to Teflon to plastic milk jugs to paint to epoxy resin would be classified in as a “polymer”. Obviously, they all have very different properties.

From what I can tell, virtually all Polymer Guns are made from either Nylon 6 or Nylon 6/6, which are both engineering grades of a thermoplastic polymer (I am assuming Kahrs are made of this but I don’t know for certain). I am guessing, but not 100% certain, that they actually are glass or carbon fiber reinforced versions for added strength, stability and impact resistance. Both neat and fiber reinforced versions of these 2 Nylon’s are used extensively in “under hood” automotive applications due to their strength, relatively high temperature stability and generally good resistance to automotive fuels and oils. They are also used in lots of other industrial applications due to their relatively low costs related to their physical properties. At the moment, in bulk pelleted form, 33% Glass Reinforced Nylon 6/6 sells for about $1.50/pound.

Here are a couple of links to chemical resistance of Nylon 6 and 6/6. http://www.unitika.co.jp/plastics/E/nylon/nylon6/07a.html (http://www.unitika.co.jp/plastics/E/nylon/nylon6/07a.html)
http://www.cable-ties.com/catalog/pdfs/nylon66_chem_resist.pdf (http://www.cable-ties.com/catalog/pdfs/nylon66_chem_resist.pdf)

Interesting to note from the charts is that Acetone appears to have no effect on Nylon, but as many of you know, acetone is very good at striping paint and lacquers.
Another interesting thing I have personally witnessed about Nylon is how it reacts with water. Nylon is hydrophilic, meaning it absorbs water and it will absorb water out of the air (humidity). The water actually acts as a plasticizer for Nylon (making it softer and more flexible). Conversely, in extremely dry environments, Nylon can become brittle. Mind you, much of the practical implications of this property are negated by fiber reinforcements.
Anyway, this is probably more than anyone really wanted to know, but I hope this helps at least clear up some questions in people’s minds. The real take away is that all “polymer” aren’t the same.

jocko
06-02-2011, 03:08 PM
ice report, the general findings have been that this non cholorinated spray cleaners are not harmful to polymer,for sure not harmful to kahrs or glocks or smith M & P, that I have owned and clean with anon cholorinated spray cleaner

ugot a dandy jPM9, shoot it like u stole it, clean it any way u feel u are comfortable with to. that little clean out hole is on the bottom of ur slide up by the breech face. If u have not alreadyvisited the kahr tech section there are two goos sticky's that will help u even more.

#1 Kahr lube chart,

# propper prepping of ur new kahr


nice report and welcome to probablythe most informative forum that I have ever been on

ripley16
06-02-2011, 03:29 PM
My concern with spray cleaners is that they are usually de-greasers. Being a user of several "dry lubes", I also wonder at the effect various cleaners have on these products. IMHO, one can over-clean their guns, going beyond what is actually necessary. Stripping all oils from my guns is just something I can't get warm and fuzzy over.

Polymer use in firearms is entering at least it's fifth decade with little or no reported degradation of useful life. Polymer seems to be an almost perfect product for pistols ...very long lived, strong, tough and offers pleasant tactile feel.

Bawanna
06-02-2011, 03:41 PM
My concern with spray cleaners is that they are usually de-greasers. Being a user of several "dry lubes", I also wonder at the effect various cleaners have on these products. IMHO, one can over-clean their guns, going beyond what is actually necessary. Stripping all oils from my guns is just something I can't get warm and fuzzy over.

Polymer use in firearms is entering at least it's fifth decade with little or no reported degradation of useful life. Polymer seems to be an almost perfect product for pistols ...very long lived, strong, tough and offers pleasant tactile feel.

If only they could make it feel, look, and smell like Coco Bolo I'd be in hog heaven. A fine piece of walnut blows my dress up far more than tupperware. Course it's progress and theres no standing in the way of it. The weight and durability issues outweigh everything old school.
I even got a rifle with a tupperware stock now, I'm starting to deal with change slowly and fighting it all the way but I'm working at it.

jocko
06-02-2011, 03:59 PM
My concern with spray cleaners is that they are usually de-greasers. Being a user of several "dry lubes", I also wonder at the effect various cleaners have on these products. IMHO, one can over-clean their guns, going beyond what is actually necessary. Stripping all oils from my guns is just something I can't get warm and fuzzy over.

Polymer use in firearms is entering at least it's fifth decade with little or no reported degradation of useful life. Polymer seems to be an almost perfect product for pistols ...very long lived, strong, tough and offers pleasant tactile feel.

ur over worrying to much, in the 50 years of polymer gun, even polymer itself has made tremendous advances, and I have no doubt these companys/chemical people do alot of testing on polymer products to make sure they do no harm. As damn near everything in these cars today are of polymer and that is where the spray cleaners first started to come to light. Wasn't to much longer that some of the gun cleaning companies picked up on it. recanned the stuff, re labeld it, charged 6 different prices and we all seem happy with it. I personally want a cleaner that cleans down to the surface, especialy in the upper steel slides, I don't want anything left but the bare cleaned metal for me to now do what I want to do with it. Lube some areas and leave some totally clean. As far as the lower section, if one feels like he doesn't want to get that polymer grip throughly cleaned, then hell, just swash it around in hot soapy water, shake dry and shoot it like u stole it. I don't see anything down in the lower section that is going to rust. Most all of these spray cleaners will clean right down to the bare metal or bare polymer, but they will not penetrate the polymer, nor have I ever read of this happening. Guarantee u that if u spray clean a 1911 and leave the grips on, those grips will be headed to bawanna for a refinish job, as most every spray cleaner, definitely including hoppe's #9 will eat into the finish that is applied to grips. I got some #9 o my J frame herretts stocks and ruined the finish,but after bawanna got done with them, they actualy look better than new.

For me anyhow, when I spray clean my kahr polymer guns, I don't worry about the lower section any more than the all steel slide.

One of the main reasons why I have loved the 3M brand was the first time I used it, that can was so powerful with its spray over everything else I have ever used. It was the power of the can spray that sold me on it besides the less than $2 bucks per can, as every spray "other" cleaner I have ever used cleaned perfectly also.

they say all this plastic sh-t in landfills willbe here a 1000 years from now. I doubt if this polymer stuff will be any different, probably gonna last even longer..

Bill K
06-02-2011, 04:33 PM
Welcome to Kahrtalk and congrats on your new PM9!

I read/studied your post and the info on the links you provided. My head hurts. :)

Bill K.

CJB
06-02-2011, 04:43 PM
Another interesting thing I have personally witnessed about Nylon is how it reacts with water. Nylon is hydrophilic, meaning it absorbs water and it will absorb water out of the air (humidity).

Yap! We make a product, part of which is certain valve that has a piston and a cylinder. There are no piston rings as such, but we use a "chevron seal" to keep things fluid tight. The seal is shaped like a chevron symbol, not made by Chevron. Anyway, we have to mold the pistons and cylinders both undersize (by different amounts), in order to have them become the right size, while in operation. The result is a very tight fit when new, requiring a vegetable based lubricant to allow functioning. In a short time (days not weeks) the parts are fully expanded, at different rates, and the lube is no longer needed - lucky since its pretty much washed out by that time.

Nice read, thanks for that