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In a previous thread I was inquiring about steel for making some wood turning tools. It appears the O1 is the most readily available in the sizes I would like. So since it has to be quenched in oil I was wondering if the following would work. After bring it up to temp I would remove it from the heat source and walk quickly out side to quench it in motor oil. Distance about 25 feet. Would the "time delay" be a problem?
What are you using as a heat source? (I've never seen a situation where the heat source wasn't in a location suitable for quenching or couldn't be easily moved to that location.)
ETA: OTOH- home heat treatment tends to be imprecise enough, I'm not sure a short quick walk wouldn't be lost in all the other variables.
You can ask Mr Google to kindly point you toward information on HEAT TREATING O1 STEEL.Quote:
Originally Posted by Tom Norton
Here, I'll do it. I found this:
https://www.popularwoodworking.com/w...ating-o1-steel
There are lots more. If you are more of a watcher than a reader there are videos. As with anything on the internet, some sources may not be reliable so you may want to seek a consensus from multiple sources.
Based on past metalworking I would quench immediately. Maybe work outside on the driveway. Have the quenching oil right next to the kiln. Be prepared for the oil to catch on fire. You can ask Mr Google about a 2-BRICK FORGE. I have a toaster oven for tempering after hardening.
This is Ed Caffrey's response a question in Ed Caffrey's Workshop. The question was about the "easy" way to heat treat O1 steel:
"Leave the blade a bit thick in the edge section. (around 1/8" or so). This prevents warpage during hardening. The blade should be finished to at least 120 grit to prevent any stress risers that could create cracks during hardening.
Ensure you have a tank large enough to submerse the blade. Fill the tank 1/2 to 3/4 full with a light oil such as automatic transmission fluid, straight SAE 30 oil, or mineral oil (this is what I currently use). Pre-heat the oil to 130-160F. (you can do this with a chunk of steel that has been heated in your forge) (using a meat/candy thermometer to measure temp) For a full quench, heat the blade slowly and evenly until a magnet will no longer be attracted to it. (around 1550F for O-1) (this can be done is the forge, or with an oxy/acteylene torch with a "soft" flame) and place the blade in the oil until it stops bubbling and fuming. Depending on the type of oil used, there will likely be some flame, and smoke, so be prepared for it. DO NOT pull the blade in and out of the oil. This will creat hard and soft spots throughout the blade. Just leave it in the oil until it gets below 400F. The blade should come out mostly dull gray in appearance..........this is a sure sign that the steel has hardened. There will be some black areas, but that is only the spots where the scale did not "blow" off. Let the blade cool in room air until you can comfortably handle it. DO NOT COOL IT DOWN BY DUNKING IT IN WATER!
Clean up the blade to at least 120 grit finish, and then temper. Tempering temps for O-1 can range from 375F to 500F depending on what you want the finished product to come out as. Lower tempering temps will leave the blade harder, but also more brittle. I would recommend starting at about 400F to 425F, and see how it performs from there. If it's too hard, you can always re-temper at 25F higher than the last temper and check it again. Once you find the tempering temp that you feel works best for you, WRITE IT DOWN. That way you don't have to re-invent the wheel every time you temper a blade of O-1. Temper for at least two hours at the chosen temp. I temper three times, allowing the blade to cool in still air to room temp, between tempering cycles.
To edge quench, follow the same procedures, but try only to bring that area of the blade you want to harden to non-magnetic. The whole intent of the edge quench is to have a blade with a hard edge and a softer spine........O-1 has some air hardening qualities, so whatever portioins of the blade you heat to non-magnetic will get hard to a certain extent. A "limiter" plate in the quench tank will help with edge quenching too. It is nothing more than a piece of aluminum chocked full of 3/8" holes, with threaded holes at each corner that will accept carriage bolts. Put the bolts in with the heads facing the bottom of the quench tank, and you can adjust the depth of the limiter plate by screwing the bolts in and out. Generally for an edge quench I look to harden between 1/3 and 1/2 of the blade's width from edge to spine. Stiffness and toughness of the finished blade is controlled by how deep the edge quench is accomplished."
But again, I wouldn't take any of this as law without researching a bit.
JKJ
I have used several different oils for quenching and usually just a torch for a heat source but have not tried a delay from heating to quenching. Possible issues that I know of are: * warping during quench (can be caused by side-ways motion during quench), * overheating the steel (causes small pits and slight loss of carbon), * steel not hot enough causing lack of hardness (if a file will cut the steel after quenching - do it over). I would be interested in hearing your results with delayed quenching.
Unfortunately walking 25' after heating up the O1 would cause too much of a temperature drop. I have learned to overheat the O1 by about 100 degrees because by the time I take the torch off of the steel and drop it in the oil it has dropped 50 degrees or more.