Hello All,
I haven't been posting much lately as I've been preoccupied with customs including honyaki and some in-house made double high carbon stainless damascus. It's been about 2 years since I last worked with M4, (I think) and I've really been wanting to revisit it.
M4 is an M class high speed steel in the same lineage as M2 and M3, which are commonly used for woodworking tool blades and drill bits (albeit sometimes modified with Cobalt in the form of M36 and M42). It has roughly equivalent toughness to MagnaCut at this hardness, and scores in the low 600-620 range in CATRA testing, ahead of Zwear, MagnaCut, and S35VN, just behind S30V, and just ahead of S45VN and Elmax. With the appropriate abrasives it sharpens to a blisteringly keen edge that lasts. According to the last line cook I sold an M4 gyuto to, approximately 4-6 weeks worth of shifts between sharpenings.
This blade is in my Sabatier inspired pattern and fully hand finished. Steels like these are extremely difficult to finish on conventional sandpaper and require diamond lapping film in its place. It still isn't easy work and I spent nearly as much time applying the hand finish as I did doing the rough grinding (perhaps in part because the diamond film appears to be 50% finer than it's rated to be), but I'm pleased with the result and am happy to say that I will once again be offering hand finishes on CPM steel knives on a limited basis (as much as my joints will allow) which should increase the food release of those offerings beyond what is possible with a belt finish.
Blade: 227mmx51mm CPM-M4 (64-65 hrc) ~800 grit hand finish
Neck: 17mmx17mm
Handle: Bolivian Rosewood and Walnut, oil finished and waxed
POB: 36mm from the handle, or over the "S" in the MM
Spine: 2.44mm at the handle, 2.34mm at halfway, .69mm 1cm from the tip
Grind: flat to convex RH bias
Weight: 158g
Relieved choil and spine
Edge: .22mm@1mm, .35mm@2mm, .55mm@5mm, .68mm@10mm from the edge, measured at the midpoint,
Asking $680 CAD equivalent (approx $500 U.S) + $30 shipping. As always, if this blade is purchased in conjunction with another I will happily deduct the shipping off of the price of the other blade.
Thanks for looking!
-Matt
I haven't been posting much lately as I've been preoccupied with customs including honyaki and some in-house made double high carbon stainless damascus. It's been about 2 years since I last worked with M4, (I think) and I've really been wanting to revisit it.
M4 is an M class high speed steel in the same lineage as M2 and M3, which are commonly used for woodworking tool blades and drill bits (albeit sometimes modified with Cobalt in the form of M36 and M42). It has roughly equivalent toughness to MagnaCut at this hardness, and scores in the low 600-620 range in CATRA testing, ahead of Zwear, MagnaCut, and S35VN, just behind S30V, and just ahead of S45VN and Elmax. With the appropriate abrasives it sharpens to a blisteringly keen edge that lasts. According to the last line cook I sold an M4 gyuto to, approximately 4-6 weeks worth of shifts between sharpenings.
This blade is in my Sabatier inspired pattern and fully hand finished. Steels like these are extremely difficult to finish on conventional sandpaper and require diamond lapping film in its place. It still isn't easy work and I spent nearly as much time applying the hand finish as I did doing the rough grinding (perhaps in part because the diamond film appears to be 50% finer than it's rated to be), but I'm pleased with the result and am happy to say that I will once again be offering hand finishes on CPM steel knives on a limited basis (as much as my joints will allow) which should increase the food release of those offerings beyond what is possible with a belt finish.
Blade: 227mmx51mm CPM-M4 (64-65 hrc) ~800 grit hand finish
Neck: 17mmx17mm
Handle: Bolivian Rosewood and Walnut, oil finished and waxed
POB: 36mm from the handle, or over the "S" in the MM
Spine: 2.44mm at the handle, 2.34mm at halfway, .69mm 1cm from the tip
Grind: flat to convex RH bias
Weight: 158g
Relieved choil and spine
Edge: .22mm@1mm, .35mm@2mm, .55mm@5mm, .68mm@10mm from the edge, measured at the midpoint,
Asking $680 CAD equivalent (approx $500 U.S) + $30 shipping. As always, if this blade is purchased in conjunction with another I will happily deduct the shipping off of the price of the other blade.
Thanks for looking!
-Matt
?
![20241123_140643[1].jpg](https://cdn.imagearchive.com/kitchenknifeforums/data/attach/356/356523-20241123-140643-1-.jpg)
