I have decided to start my 'formal' knifemaking using 1084 steel from Aldo. My questions:
1. In normalizing,is the blade put in an oven that is already heated to the proper temperature or is it put in a cold oven and then brought up to the proper temperature? Is the steel allowed to cool to room temperature before another normalization cycle?
2. In hardening a blade, are there different temperature steps in bringing the blade up to temperature before quenching the blade? Soak times before quenching?
3. In tempering, should I start with a hot oven or cold oven (similar to question 1)
I am really glad to have access to this forum. I need to learn a lot and I feel this is the place to do it. As always, TIA (thanks in advance)...Teddy
Teddy
You will receive some some direct answers to your questions but I want to also direct you to an excellent discussion on 1084 by Master Smiths Ed Caffrey, Kevin Cashen, and Brion Tomberlin which will assist you.
Click this link: http://www.americanbladesmith.com/ipboard/index.php?/topic/599-recommended-working-sequence-for-1084/
Dan Cassidy
Journeyman Smith
Send an email to Dan
Hello Teddy,
For oven work, normalizing, hardening or tempering, it is always best to bring the oven to temp and then introduce the blade. In normalizing you can simply cool until the magnet sticks again for simple grain and carbide refinement, or you can cool all the way to room temp if you have concerns about stress strain issues, the latter will fix both. With a shape as simple as a blade, in a steel as simple as 1084, there is no need for a presoak or step temperatures. Heat to a range from 1475F to 1500F and quench. Soak times with this steel are not as critical as with others, but any steel will benefit from some level of soak. Soak times are highly affected by the previous heat treatments, so if you merely normalized soak times for 1084 can be so short that they almost don’t matter, if it is fully annealed then a five minute hold can’t hurt so long as you have total control over the temperature. Also temperature accelerates time, so if you are closer to 1500F your soak will be much shorter than if it were closer to 1475F.
Allow you oven to level of at tempering temperature and then introduce the blade as quickly and smoothly as possible. 2 hours at temp is recommended. For this steel a range from 375F to 450F is useful, the lower temps for fine slicers (hunters, skinners, bird and trout etc…) and the higher range for large choppers.
"One test is worth 1000 'expert' opinions" Riehle Testing Machines Co.
