#Blades/oven cycle

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How many blades do you guys do at once in your heat treat ovens? Can you open the door, take one out, quench it and then do the next? Or is it a one blade at a time deal?? Please advise how you guys do the procedure.

Thanks.
 
I usually run three at a time, but after the first, give the others time to come back to full heat and some more soak time. I get my oven door closed back as soon as the blade clears the oven.
 
I usually put 6 or 7 in at a time,take them all out at the same time and plate quench.
Stan
 
I run three to five at a time. I pull one out and quench in plates. I pull it out of the plates around Ms, open the foil and nudge out any little bends (thin areas not touching the plates). This is only necessary with the very thin stuff. Then I pull out the next one etc. I only leave the door open for a moment.
 
I had been doing them all one at a time, but recently started doing three in an envelope at a time and plate-quenching the three-pack all at once. Works great and really speeds things up. Batch blades tested out no different from the one-at-a-time blades.
-Ben
 
I was doing 3-5 wrapped together.but found that during profiling,drilling ect,the thickness would vary but only a couple though.but this can make a difference when making folders with a bearing system.blades must be 100% flat.i find plate quenching one at a time is a fool proof way to go.also requires very little clean up of the flats.

Nathan,so i can individually wrap several,remove one and quench,remove another and quench ect? the temp change from opening oven wont effect it much?
 
I only do air harding in the oven, I was putting 3-5 in a stainless steel wrap (chewbacca) but seemed to get different coloring on the blades from inner to outer. Could not really tell any difference after tempering but I was concerned. Now I do individual wrap,one blade and one spring, and press between two aluminum plates (plate quench).

The blades are wrapped in stainless steel foil to prevent oxidation, for air hardening steels you can cool them between two plates of alumimum to prevent warping.
 
Chewy. Some of the high chrome alloy steels need to get quite hot to harden. 1850f to 2050f and they would burn up and scale if not protected from oxygen. One way to do this is put them in a stainless steel foil packet, That way no air. Also, many of these steels don't need to cool really fast to harden well, so, you plate quench. Place the packet with the hot knife between two large pieces of aluminum and clamp it. This keeps the blade straight and sucks the heat out fast enough to get them fully hard. Some of the manufactures specs for these steels just callf for moving air on them to cool. You have as much as a minute or more to cool them from 1850 to say 700 where as 1095 you only have .8 second from 1500
 
balibalistic said:
Nathan,so i can individually wrap several,remove one and quench,remove another and quench ect? the temp change from opening oven wont effect it much?
Click to expand...


I'm sorry, I never noticed your question directed to me.

We run up to the heat we use to get the stuff into solution we want. A light reduction in temperature before quenching is not going to re-participate any of that stuff back out of solution again. The other blades left in the furnace are not cooling off cool enough for long enough to change any of that. Remember, it is not the temperature the steel is at once the quench starts, it is the temperature it was soaked at (within reason). An extreme example of this is 1095, which must "get under the nose" in under a second. Well, that doesn't mean you have to run from the furnace to the quench in under a second because the clock is ticking. The clock doesn't really start to tick until you get under a critical temperature.

It would probably be a different story if the blades were getting down from 1850 to 1750, but they're not.
 
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