SoCal Dave Posted September 18, 2015 Share Posted September 18, 2015 I made a center punch for a friend out of coil spring. After a period of time, he said the point became dull. I'm not sure of the amount of use or abuse it took. I quenched it in oil to a golden straw color. In making a new one, I was thinking of using kasinet but didn't know if it would be best to treat it before or after running the colors? I think that if I treated it with Kasinet after tempering, I would loose some of the tempering. Before tempering, it might effect the tempering? Any suggestions? Quote Link to comment Share on other sites More sharing options...
ThomasPowers Posted September 19, 2015 Share Posted September 19, 2015 Ah that stuff is used at a red heat so tempering to a temp 1/3 or so before hand is just a waste of effort. Quote Link to comment Share on other sites More sharing options...
stan Posted September 19, 2015 Share Posted September 19, 2015 Even good name bought center punches need re sharpening, I made a coil spring one some time ago using similar methods as you I think if it was tempered to harder than golden straw the tip would probably fail. Quote Link to comment Share on other sites More sharing options...
Charlotte Posted September 19, 2015 Share Posted September 19, 2015 Kind of depends on what the usage is as to how what material to use. A while back and also recently I invested in H13 round for forge tools. If you have a coal forge it is possible to forge H13 between the forging temp is some where between bright yellow and white, I have forged chisels for hot work that way. For a center punch buy 3/8 drill rod grind to shape. Critical Temperature:Ac1: 1544°F (840°C)Ac3: 1634°F (890°C)Ar1: 1475°F (802°C)Ar3: 1418°F (826°C)Preheating: To minimize distortion in complex tools use a double preheat. Heat at a rate not exceeding 400°F per hour (222°C per hour) to 1150-1250°F (621-677°C), equalize, then raise to 1500-1600°F (816-871°C) and equalize. For normal tools, use only the second temperature range as a single preheating treatment.Austenitizing (High Heat): Heat rapidly from the preheat. Furnace or Salt: 1800-1890°F (982-1032°C) For maximum toughness, use 1800°F (982°C) For maximum hardness and resistance to thermal fatigue cracking and wear use 1890 (1032°C). Soak at temperature for 30 to 90 minutes.Quenching: Air, pressurized gas, or warm oil. Section thicknesses up to and including 5 inches (127 mm) will typically fully through harden when cooled in still air from the austenitizing treatment. Sections greater than 5 inches (127 mm) in thickness will require accelerated cooling by using forced air, pressurized gas, or an interrupted oil quench to obtain maximum hardness, toughness and resistance to thermal fatigue cracking.For pressurized gas quenching, a minimum quench rate of approximately 50°F per minute (28°C per minute) to below 1000°F (538°C) is required to obtain the optimum properties in the steel.For oil, quench until black, about 900°F (482°C), then cool in still air to 150-125°F (66-51°C).Tempering: Temper immediately after quenching. The typical tempering range is 1000-1150°F (538-621°C). Hold at the tempering temperature for 1 hour per inch (25.4mm) of thickness, but for 2 hours minimum, then air cool to ambient temperature. Double tempering is required. To maximize toughness and tool performance, a third temper is often used as a stress relief after all finish machining, grinding, and EDM work are completed on the tool. Quote Link to comment Share on other sites More sharing options...
Frank Turley Posted September 23, 2015 Share Posted September 23, 2015 duh Quote Link to comment Share on other sites More sharing options...
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