Don't like the curve of your cz75 stock trigger?

[philthephlier]

straighten it after annealing it. It is a hardened steel part so it has to be softened to straighten it. Measure the distance from the center of the top hole, (the trigger pivot hole) to the bottom of the trigger. Straighten the curve by tapping on it with an 8 oz. ball peen hammer until the trigger grows in length by about .050". I am not sure if the trigger needs to be rehardened or not. I am thinking it does not. It's not a trigger with a sear. If you want it hard again though, Kasenit and the torch you used to anneal it will get you there.

[oldred]

straighten it after annealing it. It is a hardened steel part so it has to be softened to straighten it. Measure the distance from the center of the top hole, (the trigger pivot hole) to the bottom of the trigger. Straighten the curve by tapping on it with an 8 oz. ball peen hammer until the trigger grows in length by about .050". I am not sure if the trigger needs to be rehardened or not. I am thinking it does not. It's not a trigger with a sear. If you want it hard again though, Kasenit and the torch you used to anneal it will get you there.

Actually Kasenit probably won't be needed and could even cause problems unless the part is case hardened mild steel which is unlikely, if it is alloy steel then what's needed is to heat/quench to re-harden it then temper it to restore it's ductility. You don't want to use Kasenit or any other type of case hardening process on alloy steel. Even if it was mild steel that had been case hardened then simply heating and quenching would be all that's needed unless the already carbon or compound hardened surface of the part has been filed/sanded away or otherwise removed. Using "Kasenit" or "Cherry Red" (Kasenit is no longer available and has been off the market a few years now due to toxicity) to case harden an alloy or high carbon steel will make it prone to cracking and this is especially true if it's not tempered after hardening. Before attempting to harden gun parts, especially modern gun parts, it's imperative that the Smith know just what kind of steel he is working with so that the proper procedure can be followed because these procedures are not interchangeable, Kasenit, Cherry Red or just Carbon packing can ruin an alloy steel part!



Just a note about Kasenit since there's still some left in people's shops, it was removed from the market because the EPA deemed it to be toxic because of Cyanide but years of safe use of this popular product does not seem to indicate any real problems and it appears to be another case of over-reaction by the EPA!!!!!

[Harry O]

"Just a note about Kasenit since there's still some left in people's shops, it was removed from the market because the EPA deemed it to be toxic because of Cyanide but years of safe use of this popular product does not seem to indicate any real problems and it appears to be another case of over-reaction by the EPA!!!!!"

I have a half-can of Kasenit that I still use from time to time. Also a little bit of Carbon-TetraChloride for cleaning (used it for chamber cleaning on a S&W .22Jet before shooting to keep the cases from backing up). And a few ounces of Sperm Oil (for when regular oil fails). And a little bit of Mercury (works great for really hard to clean leading).

All were bought when they were legal, but if I am ever raided by any layer of government, I have no doubt that I would be portrayed as public enemy no. 1 even before they get to my "stockpile" of ammunition.

[oldred]

Kasenit does contain traces of cyanide and I suppose someone at the EPA saw that and went berserk without actually looking at the facts. When I tried to buy some after using the last of mine I discovered it had been removed from the market because of possible toxicity so naturally I was concerned due to the fact I had used so much of it over the years but Mr Google, who seems to know everything, could not find any scare stories about the toxic effects of this EPA designated sinister concoction. I have used it for years and have been exposed to those "noxious" fumes many times without any apparent ill effects (other than the stink!!!) so I will continue to use what little I have left from the small can I did manage to find until it's gone, the good news is that "Cherry Red" seems to be a very capable and easy to obtain replacement! I have been using "Cherry Red" on larger parts that I did not want to use my remaining Kasenit on and I have been quite happy with the results, I have been able to obtain a very hard case well over .030 deep by packing the part in "Cherry Red" then heating in the oven similar to Carbon packing except it is only soaked for about 5 minutes after reaching temperature. Using the traditional method of heating, dipping in the compound, reheating then quench works quite well also but the case is not nearly as deep.

[Jeff Michel]

I have been meaning to try it, but I've heard that granulated table sugar does work as a substitute for case hardening compounds.

[Walter Laich]

I was going to try sugar but I'm diabetic so that's out for me :wink:

[oldred]

I have been meaning to try it, but I've heard that granulated table sugar does work as a substitute for case hardening compounds.



That's interesting, I haven't heard of that before, easy enough to try it however! Next time I fire up my oven I will try that on a small piece of mild steel then check the hardness and the depth of hardness, is that supposed to be just a heat, dip and quench like with Kasenit or is it to be packed like a carbon pack?

[seaboltm]

Sugar is has a lot of carbon in it that is easily separated from the molecule. Sugar melts at a low temperature (relatively low). I would think melting sugar with a propane torch and dipping would work.

[Jeff Michel]

If I remember correctly, I read it in a construction article that was published in Model Engineer magazine sometime in the last year. The writer (Doug Hewson, I think) didn't go into detail other than he utilized sugar in the same manner as Kasenit (heat, dunk, quench) He did mention that Kasenit had been banned, that didn't surprise me since he was in the UK. What I didn't know that it was also targeted in the US. Saving us from ourselves, just like removing that insidious cadmium from silver solder a few years back. I'll snoop around and see if I can find the original article to verify his technique.

[oldred]

just like removing that insidious cadmium from silver solder a few years back. I'll snoop around and see if I can find the original article to verify his technique.

I am going to have to take exception to Cadmium in Silver solder, that stuff was dangerous, they didn't use that Skull and Cross Bones on the warning label for a joke!!!!! Back in '75 at a mine in Kentucky we had a guy get down on "Harris" Silver solder and the guy nearly died, he still to this day suffers from the lung damage. On another job within the same company it happened again about two years later and they came around and collected the stuff from the warehouses then forbid it's use company wide. The hazards of Cadmium in that old Silver solder is nothing to scoff at!

[oldred]

Ok here's what I have found about Sugar, heating and dipping followed by quenching similar to using Kasenit or Cherry red does seem to change the surface hardness of mild steel but apparently not to any useful degree. It was noticeably harder using a file to test (I won't have access to a tester until next week) but the "case" is extremely thin, in fact just barely there, and could easily be broken through with the file. With all the Carbon in Sugar I suppose it might work well using the pack method but I see no advantage to doing that over charcoal and possibly some disadvantages. I am just guessing but I am going to assume that the reasoning behind the Sugar is all the Carbon the part would be exposed to but the flaw to that is that with Carbon it's takes a long time exposure for the Carbon to be absorbed into the metal, Kasenit and Cherry Red rely on other chemicals to harden almost instantly.

So my brief testing would seem to indicate that while Sugar can indeed impart some hardness into the metal surface it's much too thin to be of any practical use on firearm parts.