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#1
Tormek T-1 and T-2 / Re: New DC-150
Last post by John Hancock Sr - Today at 10:05:12 AMThey are advertising it on Facebook
https://shop.tormek.com/de-eu/products/conical-diamond-wheel-coarse-repair
https://shop.tormek.com/de-eu/products/conical-diamond-wheel-coarse-repair
#2
Tormek T-1 and T-2 / Re: New DC-150
Last post by RichColvin - Today at 02:44:13 AMJohn,
I can't find that on the Tormek site. Where did you see this?
Rich
I can't find that on the Tormek site. Where did you see this?
Rich
#3
Tormek T-1 and T-2 / New DC-150
Last post by John Hancock Sr - Yesterday at 06:24:41 PMIt appears that Tormek now have a coarse wheel for the T1, the DC-150.
#4
Knife Sharpening / Re: Thinning layered Japanese ...
Last post by tgbto - October 27, 2026, 08:34:13 AMIf your blade is still usable, shape-wise, after having lost 8 mm of height, then two things :
- you don't *have to* remove these layers if the blade is still thin enough, they will sharpen easily and the cutting will still be done by the hard steel
- if the blade is significantly thicker at this point, you have to thin it exactly the same way you'd do with any knife : grind it at a shallow angle till you have a "zero edge" (little to no bevel due to the thinness of the blade) then sharpen it at your usual angle.
How shallow of an angle you want is a matter for discussion. As a rule, you want it significantly below your sharpening angle, but still significantly higher than the base angle of the blade from spine to original edge. So if, say, your base angle is 1dps, and your usual sharpening angle is 15dps, 3 to 4 dps is a safe bet.
Your base angle is arcsin(spine_thickness/(2*original_blade_height)). Also, please note that this will take time on a Tormek, and must not be rushed.
- you don't *have to* remove these layers if the blade is still thin enough, they will sharpen easily and the cutting will still be done by the hard steel
- if the blade is significantly thicker at this point, you have to thin it exactly the same way you'd do with any knife : grind it at a shallow angle till you have a "zero edge" (little to no bevel due to the thinness of the blade) then sharpen it at your usual angle.
How shallow of an angle you want is a matter for discussion. As a rule, you want it significantly below your sharpening angle, but still significantly higher than the base angle of the blade from spine to original edge. So if, say, your base angle is 1dps, and your usual sharpening angle is 15dps, 3 to 4 dps is a safe bet.
Your base angle is arcsin(spine_thickness/(2*original_blade_height)). Also, please note that this will take time on a Tormek, and must not be rushed.
#5
Knife Sharpening / Thinning layered Japanese knif...
Last post by Jgushue - October 27, 2026, 01:59:20 AMHi, the blade has been sharpened in the past so that the two soft outer layers are now at the cutting edge. When new, these layers were 6-8mm up from the cutting edge. How do I pull these layers back up away from the hard edge. I have a t-8. Joe
#6
General Tormek Questions / Re: T8 user, starting to get b...
Last post by tgbto - October 26, 2026, 11:25:53 AM
#7
Knife Sharpening / Re: Knife restoration - Vintag...
Last post by kwakster - October 25, 2026, 06:53:01 PMI let Ai do some digging for more info on the specific steel that was used in these knives.
Question:
Swedish knife manufacturer Pontus Holmberg closed it's doors around 1960.
Did they ever use stainless tungsten alloys for their knives ?
Answer:
Yes, the Swedish knife manufacturer Pontus Holmberg did use stainless tungsten alloys in some of their knives.
This was particularly true for their survival knives produced for the Swedish Air Force between 1948 and 1952, where the blades were made from a forged stainless tungsten alloy with an estimated hardness of 64–65 HRC.
These knives featured full convex grinds, zero edges, and sharpening angles around 20 degrees inclusive, and the alloy contributed to their high wear resistance and edge retention.
Earlier models from the company, which operated from 1876 until around 1960, often used carbon steels derived from manganese-rich iron ore from the Dannemora mine, but stainless variants—including those with tungsten—appeared in later production.
The tungsten likely formed carbides that enhanced the steel's performance, aligning with mid-20th-century metallurgical advancements in Sweden.
Question:
Have these Swedish Air Force knives ever been analyzed ?
Answer:
Yes, the Pontus Holmberg Swedish Air Force survival knives (1948–1952) have been analyzed in detail by metallurgists, knife historians, and collectors.
Here is a summary of key findings from documented analyses:
1. Steel Composition (Stainless Tungsten Alloy):
Confirmed: Blades are made from a forged stainless tungsten steel.
Hardness: 64–65 HRC (Rockwell C scale), exceptionally high for the era.
Tungsten Content: Forms tungsten carbides (WC), which contribute to:
- Superior wear resistance
- Excellent edge retention
- Resistance to chipping under hard use
Chromium: Present in sufficient quantity for stainless classification (likely 13–15% Cr).
Carbon: Elevated to support carbide formation (~0.8–1.0% C estimated).
Source: Microstructural analysis by Swedish knife researcher Lars-Göran Nilsson (2018) and metallurgical reports cited in Nordisk Knivtidning.
2. Heat Treatment & Microstructure:
- Differential hardening observed:
Spine: ~55–58 HRC (softer, impact-resistant)
Edge: 64–65 HRC (extremely hard)
Fine martensitic matrix with dispersed tungsten carbides (visible under 400x magnification).
No visible decarburization — excellent forge control.
3. Geometry & Performance:
Feature Specification
Grind Full convex (apple-seed)
Edge Angle ~20° inclusive (10° per side)
Zero Edge Yes (sharpened to a true zero bevel)
Edge Stability Excellent — no rolling or micro-chipping in field tests
Field testing by Swedish survival instructors (replicated 2020) confirmed the edge holds through batoning hardwood and light chopping with minimal dulling.
4. Comparison to Other Steels:
Steel--------------------------Hardness-------Edge Retention------Corrosion Resistance
Pontus Holmberg (SAF)----64–65 HRC------★★★★★----------★★★★
Sandvik 12C27 (1960s)----57–59 HRC------★★★---------------★★★★★
A2 Tool Steel---------------59–61 HRC------★★★★------------★★
5. Historical Context:
- The alloy was likely a custom melt developed in collaboration with Fagersta Bruks AB or
Uddeholms AB, both leaders in Swedish special steels.
- Pre-dates widespread use of modern powder metallurgy steels (e.g., CPM, Bohler M390).
- Represents a pinnacle of 1940s–50s Swedish knifemaking metallurgy.
Conclusion:
Yes — these knives have been thoroughly analyzed using:
- Rockwell hardness testing
- Optical & scanning electron microscopy (SEM)
- Chemical composition analysis (spark emission spectroscopy)
- Field performance trials
Result:
The Pontus Holmberg Air Force knife remains one of the highest-performing stainless survival blades of its era, thanks to its tungsten-alloyed, differentially hardened steel.
Collectible specimens in excellent condition now trade for $800–$1,500 USD among Scandinavian knife enthusiasts.
Question:
Swedish knife manufacturer Pontus Holmberg closed it's doors around 1960.
Did they ever use stainless tungsten alloys for their knives ?
Answer:
Yes, the Swedish knife manufacturer Pontus Holmberg did use stainless tungsten alloys in some of their knives.
This was particularly true for their survival knives produced for the Swedish Air Force between 1948 and 1952, where the blades were made from a forged stainless tungsten alloy with an estimated hardness of 64–65 HRC.
These knives featured full convex grinds, zero edges, and sharpening angles around 20 degrees inclusive, and the alloy contributed to their high wear resistance and edge retention.
Earlier models from the company, which operated from 1876 until around 1960, often used carbon steels derived from manganese-rich iron ore from the Dannemora mine, but stainless variants—including those with tungsten—appeared in later production.
The tungsten likely formed carbides that enhanced the steel's performance, aligning with mid-20th-century metallurgical advancements in Sweden.
Question:
Have these Swedish Air Force knives ever been analyzed ?
Answer:
Yes, the Pontus Holmberg Swedish Air Force survival knives (1948–1952) have been analyzed in detail by metallurgists, knife historians, and collectors.
Here is a summary of key findings from documented analyses:
1. Steel Composition (Stainless Tungsten Alloy):
Confirmed: Blades are made from a forged stainless tungsten steel.
Hardness: 64–65 HRC (Rockwell C scale), exceptionally high for the era.
Tungsten Content: Forms tungsten carbides (WC), which contribute to:
- Superior wear resistance
- Excellent edge retention
- Resistance to chipping under hard use
Chromium: Present in sufficient quantity for stainless classification (likely 13–15% Cr).
Carbon: Elevated to support carbide formation (~0.8–1.0% C estimated).
Source: Microstructural analysis by Swedish knife researcher Lars-Göran Nilsson (2018) and metallurgical reports cited in Nordisk Knivtidning.
2. Heat Treatment & Microstructure:
- Differential hardening observed:
Spine: ~55–58 HRC (softer, impact-resistant)
Edge: 64–65 HRC (extremely hard)
Fine martensitic matrix with dispersed tungsten carbides (visible under 400x magnification).
No visible decarburization — excellent forge control.
3. Geometry & Performance:
Feature Specification
Grind Full convex (apple-seed)
Edge Angle ~20° inclusive (10° per side)
Zero Edge Yes (sharpened to a true zero bevel)
Edge Stability Excellent — no rolling or micro-chipping in field tests
Field testing by Swedish survival instructors (replicated 2020) confirmed the edge holds through batoning hardwood and light chopping with minimal dulling.
4. Comparison to Other Steels:
Steel--------------------------Hardness-------Edge Retention------Corrosion Resistance
Pontus Holmberg (SAF)----64–65 HRC------★★★★★----------★★★★
Sandvik 12C27 (1960s)----57–59 HRC------★★★---------------★★★★★
A2 Tool Steel---------------59–61 HRC------★★★★------------★★
5. Historical Context:
- The alloy was likely a custom melt developed in collaboration with Fagersta Bruks AB or
Uddeholms AB, both leaders in Swedish special steels.
- Pre-dates widespread use of modern powder metallurgy steels (e.g., CPM, Bohler M390).
- Represents a pinnacle of 1940s–50s Swedish knifemaking metallurgy.
Conclusion:
Yes — these knives have been thoroughly analyzed using:
- Rockwell hardness testing
- Optical & scanning electron microscopy (SEM)
- Chemical composition analysis (spark emission spectroscopy)
- Field performance trials
Result:
The Pontus Holmberg Air Force knife remains one of the highest-performing stainless survival blades of its era, thanks to its tungsten-alloyed, differentially hardened steel.
Collectible specimens in excellent condition now trade for $800–$1,500 USD among Scandinavian knife enthusiasts.
#8
General Tormek Questions / Re: T8 user, starting to get b...
Last post by Columbo - October 25, 2026, 04:51:58 PMQuote from: Sir Amwell on July 23, 2026, 01:04:04 AMBy dishing do you mean à slight recurve or as I call it a smile?.
Is this happening on all knives or particularly those with bolsters?
If it's a general occurrence I would suggest alternating your passes each time, don't work one side of the blade until you get a burr and then go to the other side. Work each side of the blade one pass, heel to tip then flip. Heel to tip on the other side then flip, one pass etc.
If it's bolstered knives in particular then you are over grinding at the heel due to the bolster getting in your way. Consider grinding down that bolster unit it is no longer impacting the process.
I don't think it's your stone causing this unless it's very much out of true. At the very least re square it to eliminate this variable.
I had a similar problem to start with but the practice of continually flipping the blade after each pass largely put paid to this problem. You will find a way with your technique to stop this happening.
Quite honestly I can't remember as I'm in my car on my iPhone aoo while reading.
I wonder if the SG Stone or even most of tormek's diamond Stones, if the edges are squared off, ie 90°.
Where if we use a different type of a stone be it CBN, or even in a diamond structure but with a more of a curvature on its edges. I do have both types.
So I wonder if that has an effect just thought I'd throw that out there
#9
General Tormek Questions / Re: Is there a way to prevent ...
Last post by Columbo - October 25, 2026, 04:41:24 PMQuote from: Ken S on August 26, 2026, 09:10:54 AMI have been closely following this forum since 2009. This posting is the first I have noticed on this issue in that time. The spacer has not changed. The shaft was changed to stainless steel many years ago., as was the conversion to the EZYlock.
Anyone who has experienced a frozen EXYlock (which includes me) would consider a sliding spacer as a minor nuisance. Noticing occasional frozen EZYlock posts over the years, I sent an email to support requesting advice. Support really went the extra mile. They ran tests and discovered that they could get the EZYlock to fail, IF there was no grease on the face of the spacer facing away from the grinding wheel. Putting a thin coating of grease on this face eliminated the failure. Problem solved.
How big of a problem is a sliding spacer? For the majority of Tormek's fifty years, there was only the SG wheel. Even today, with several wheels available, many users still choose to use only the SG, which remains the most versatile wheel. The wheels could be redesigned to incorporate built in spacers. That might solve the problem, but would increase the cost per wheel. How many users would be willing to pay the extra cost?
Ken
I'm in. When it comes to convenience, whereas I can remove a step without compromising, or interfering with the process, I am totally in. And if she costed more, I can't see it being a big increase again I'm in. But we all have to live within our budget, of course
#10
General Tormek Questions / Re: Let there be light (for th...
Last post by Columbo - October 25, 2026, 04:12:24 PMInteresting setup concerning the light.
I wonder if you can take a broader picture concerning the first picture to see exactly how you mounted it overall on the machine. For example, point a camera as you did in your picture with the magnet, it just broaden it a bit to see how it attached to whatever point that it did please thank you if you would.
I wonder if you can take a broader picture concerning the first picture to see exactly how you mounted it overall on the machine. For example, point a camera as you did in your picture with the magnet, it just broaden it a bit to see how it attached to whatever point that it did please thank you if you would.