How to temper TRS springs?

[LRB]

We use 4140 steel on all our lock parts except frizzens and springs which are 6150.

This is the type of steel that TRS uses and they say they use a water quench, soo if they do it should I?

I wouldn't, but apparently they get away with it. I would use warmed vege oil. Canola, or peanut, or any thing similar rather than water. 6150 is a high chrome steel, and should need only a medium speed quench to get hard. Plain water is a violent, fast, uneven quench, and by all rights, should cause it to crack. That it doesn't is amazing to me. As far as temper, I would try Jerrys advice.

 

[Stophel]

I have done only a few TRS 4140 parts, so I have no long-term experience with them, but I have had good luck hardening them with Kasenit and quenching in warm (and dirty) water. This gives me a good hard surface, and I then temper them down to brown, which still leaves the surface hard, but should increase the shock resistance of the lower-carbon steel inside. SEEMS to do well this way.

 

[LRB]

It should do fine Chris.

 

[jerrywh]

Wick.
I always block lock plates when I case harden them but occasionally one will warp. I once thought I could bend the plate back because the interior was supposed to be soft but the plate snapped at the tumbler hole. Well I tig welded it up and did it over, But it was a real pain because it was engraved. Thats' why I asked.

 

[TARL01]

Wick, I thought I knew at least a little about this, but obviously I was wrong. Is there a good book you can recommend concerning tempering, hardening, and anealing?
Thanks, Woody

 

[LRB]

I don't know of any one book that will cover everything. There are a number of metallurgy books, and heat treating manuals, full of charts and graphs and big words, but they bore me to tears, plus many of those often contradict each other in some areas. I could give more books to not read or go by, than to read. There are other books in plain language on how to make knives, or work with high carbon steels, but I have yet to find one that I would recommend. One major problem with common level info on blade steels and how to work them is learning to separate the BS from that which is metallurgically sound and proven, and doesn't defy the laws of physics. One example would be the practice of edge packing that some smiths still use. It is physically impossible to do that, but you may yet find it mentioned in some how to books. Another would be quenching a blade as soon as it reaches non-magnetic heat. No steel will reach it's potential quenched at that low of heat. I would suggest that you pick one, or a few blade steels that you might use, then concentrate on finding info on them. I will PM you some good basic info.

 

[LRB]

Jerry, did you temper after the case hardening? If 4140, it can get as hard as 60Rc. It also requires higher temper heats than one would think. I would believe the heat bend and water trick might work, but you might want to do a test run on a scrap piece. Sent you a PM.

 

[bioprof]

We use 4140 steel on all our lock parts except frizzens and springs which are 6150.

This is the type of steel that TRS uses and they say they use a water quench, soo if they do it should I?

I wouldn't, but apparently they get away with it. I would use warmed vege oil. Canola, or peanut, or any thing similar rather than water. 6150 is a high chrome steel, and should need only a medium speed quench to get hard. Plain water is a violent, fast, uneven quench, and by all rights, should cause it to crack. That it doesn't is amazing to me. As far as temper, I would try Jerrys advice.

Have you looked at their prices for a completed lock? I think it's likely that they mainly sell parts and not many completed locks.

 

[LRB]

Yep. Seen their prices. I have little doubt that you are absolutely correct.