01-08-2018, 09:33 AM
(01-07-2018, 04:10 PM)Jan Wrote: Mr. Scott, thanks for sharing your experience. It is very important for me now, esp. your info that you harden your only one blade at time.
Your Lindberg is top laboratory furnace with special refractory plate heating elements. I cannot believe your price. I have paid some $80 for a box of 20 special insulating bricks. Next on my budget is the Kanthal wire and an inexpensive controller for some $75.
Jan
one blade at a time just works best for me. O1, O7, and similar steels only require 10 minutes or less at temperature to harden, I do not pre-heat. hardening is a function of temperature and time. it takes 2 minutes to quench and clamp a blade. If I did 5 blades at once, blade 5 would be a temperature almost twice as long as blade 1, which can effect grain size and quenched hardness.
I bought the furnace from an electronic salvage house, imagine dozens of 4'x4'x4' boxes overflowing with keyboards, displays, cables, and laptops. I guess that did not know how valuable the item was and just wanted it gone.
I posted links to several places that sell Kanthal elements already coiled, it should save a lot of time over having to make your own coils.