Tormek Community Forum

In the Shop => Knife Sharpening => Topic started by: Sam Sloane on August 06, 2019, 05:48:33 PM

Title: My First Super Steel Knives
Post by: Sam Sloane on August 06, 2019, 05:48:33 PM
Guys,

I have a handful of Outdoorsmen knives to do......they are made from

M390  59-61 RHC
K340  57-59 RHC
Lohman Nicolox 1.4152.03   RHC 61

Right now they come in at Bess Scores of 200-350.....

I have only SG250 and a dual Paper Wheel setup using 14 Micron, and 3 Micron diamond (and Tormek leather wheel with compound)

Whats my best approach to doing these?

I dont want to screw up.......I have never tried anything with these high RHC numbers.

I would love to see my first sub Bess score of 70 on these!

Thanks in advance,

Sam
Title: Re: My First Super Steel Knives
Post by: wootz on August 07, 2019, 12:56:16 AM
With what you have you can sharpen Niolox, and with some effort the K340.
Title: Re: My First Super Steel Knives
Post by: Sam Sloane on August 07, 2019, 05:47:32 AM
thank you Wootz!......you are awesome!
Title: Re: My First Super Steel Knives
Post by: Sam Sloane on August 07, 2019, 05:53:32 AM
so the M390???.....too hard?

what about just paper wheels with diamond?.....Micro bevel and already decent apex???
Title: Re: My First Super Steel Knives
Post by: wootz on August 07, 2019, 01:08:40 PM
Quote from: Sam Sloane on August 07, 2019, 05:53:32 AM
so the M390???.....too hard?

what about just paper wheels with diamond?.....Micro bevel and already decent apex???

By the time you apex the M390 on your SG wheel, the steel will be so tired that as you start cutting it will be chipping from the vanadium carbides tear-out. Combination of high vanadium, 60+ HRC hardness and relatively low hardness of the aluminium oxide SG wheel will result in the apex fracturing.

Niolox and K340 are molybdenum rich steels - molybdenum imparts toughness to these alloys, somewhat relieving them form the M390 problems.

They all can be beveled on the SG wheel.
But for the edge stability, edge in the hard alloy steels should be set on diamond or CBN #1000 - 1200.
It is impossible to set edge on paper wheels with the diamond paste - paper wheels are for deburring and honing the edge that is already there.