Members J Hayes Posted September 12, 2014 Members Report Posted September 12, 2014 (edited) The reason for the long grind is to get the cutting angle low, 15 degrees in the case of my weaver. Blade is 1.86" along the bottom flat and .5" thick on the spine. Shorter grind equals steeper angle and a steeper angle makes for a harder pull. I notice this a lot with a few of my old round knives, a small Rose that has a hefty shoulder is more difficult to push than a small Gomph that has a fine thin taper, that one cuts like butter. Both knives are very sharp, just that thicker blade on the Rose has to push more material aside to make the cut. The bimetal blades were probably made for cost savings way back when, not sure if there's a good reason in current times for a bimetal splitter blade other than sharpening might be a touch easier by only have 3/8"-1/2" of hard steel to grind. Bimetal splitter blades have the leading edge as tool steel, not really "within" just leading the way. Just my views Jeremy Edited September 12, 2014 by J Hayes Quote
Members deloid Posted September 12, 2014 Members Report Posted September 12, 2014 Hi Jeremy, I agree that 15 degrees would be a pleasure to cut with but theoretically it shouldn't stay sharp as long as a 22 degree edge or a grind with a secondary bevel. It seems like you are pleased with the Weaver blade. It must be a durable steel. Is it harder to resharpen like most long wearing steels? You wrote "bimetal splitter blade other than sharpening might be a touch easier". I would have to argue with this point. The purpose of having mild steel such as wrought as a core was twofold. One was cost savings, the other was resilience. With differential heat treating or purposeful quenching this isn't really necessary anymore (arguable). The edge though is only supposed to be carbon steel (hard steel)so sharpening shouldn't be any easier. Incidentally, though I'm sure you already know this, the Weaver at 1/2 inch is thicker than the Osborne at 3/8 inch at the spine. This is also helpful to consider (in favor of a Weaver blade). Dean Quote
Members J Hayes Posted September 12, 2014 Members Report Posted September 12, 2014 (edited) The bimetal splitter blade isn't wrapped, just a hard piece fused to the leading edge. You're probably right in it not being any easier to sharpen, just the rear 3/4 of the blade will grind easier than the front hardened portion. So far I'm very pleased with the Weaver, good hard steel. The Osborne I had was about 17degrees. Edited September 12, 2014 by J Hayes Quote
Members deloid Posted September 12, 2014 Members Report Posted September 12, 2014 I'm glad this came up Jeremy. It's nice to hear from someone who has handled the Osborne and Weaver. Since I will be grinding a new profile from O1 steel I might as well use a thicker piece and try the Weaver grind on my Osborne frame. Dean Quote
Moderator bruce johnson Posted September 12, 2014 Moderator Report Posted September 12, 2014 Dean, I got your phone message and came at a good time. I needed a new blade for one I have and had ordered an Osborne replacement yesterday. Hopefully this will go directly onto the old frames but nothing Osborne does surprises me. I will give a feedback on the new Osborne blades once I get it, sharpen, and test it. They are supposed to have a bimetal blade but shorter section of the hardened steel than the old ones. We'll see. Quote
Members J Hayes Posted September 13, 2014 Members Report Posted September 13, 2014 Let us know how it comes out. I do think even the old ones started life in the 15-17degree range, over the years I could see how someone would just grind the leading edge slowly increasing the angle over the years. Both my CS and HF Osborne were ground nearly all the way to the spine leaving maybe a 1/4" of flat on the top. Keep track of what it takes you to make that blade, I'd bet you could sell a few Quote
Members deloid Posted September 13, 2014 Members Report Posted September 13, 2014 I will make a few blades out of my O1 stock. I have the length and slot from my present 84. I measure 3/8th inch thickness and perhaps I should keep it there if that is what the Osborne 84s were supposed to have. I don't know what the original width was due to wear on my now pretty much exhausted blade. Any help with this? Quote
Members J Hayes Posted September 13, 2014 Members Report Posted September 13, 2014 (edited) My old HF Osborne is 1.38" and .427" thick, the new Weaver is 1.86" if that helps at all. The HF is over 100 years old and is likely much shorter than it was when new. My guess is the blade Bruce will be getting from Osborne will be about 1.75", now we just wait in suspense for him to report back....... Edited September 13, 2014 by J Hayes Quote
Members deloid Posted September 13, 2014 Members Report Posted September 13, 2014 Thank you so very much! I was guessing that adding the original lines and width would come to around 1.75" but it's nice to read this from you. Yes, Bruce will undoubtedly know. Quote
Members deloid Posted September 13, 2014 Members Report Posted September 13, 2014 I have been reflecting on the blade design and now I think I see a purpose to the lower carbon steel weld. I suspect that the vibrations from pulling on certain tough leather may transmit too harshly to the cast frame. Mild steel would soften these vibrations and also render the attachment (nut to frame)less prone to damage. Theoretically at least. If so, I can forge weld wrought to the tool steel. Unfortunately I have a limited supply of wrought iron. Quote
Members StrigaMort Posted September 15, 2014 Members Report Posted September 15, 2014 I'm very interested in reading this. I'm especially interested in watching what happens with your blade design Dean. Leather is my primary concern, but I come to leather directly from the knife world. I have the means to heat treat simple eutectoid steel (1080/84) properly, so your experience with o1 will be fun to watch. Please keep us updated. Quote
Members deloid Posted September 15, 2014 Members Report Posted September 15, 2014 I'll certainly let you know on this forum. I too started with forging then stock removal. I am still a member of the ABS our local Idaho Knife Association and the CKCA. My wife has taken the leather business to new wonderful heights and while I love helping as I can I have been pulled from my primary interests. This is at least one way that I can get back to working metal. perhaps I might sneak in a couple of hunters and the 9 1/4 inch flat grind Gents bowie that used to drive me nuts (getting the grind right). It's funny, I first started making knife sheaths because I made knives and more importantly, Paul Long gave me his time and attention to get me started correctly. From there I made a belt for my wife. This inspired her and she took on the work herself with drive, passion and creativity. Now I assist and troubleshoot. Thanks for your expressed interest! Dean Quote
Members StrigaMort Posted September 15, 2014 Members Report Posted September 15, 2014 Hey that's cool. Small world. I bug Paul at least once a day (ears burning Paul?) over on Bladeforums. I know he's here as well, although I don't think I've bumped into him. You ever get some time, stop by and say hi, I'd love to see your work. Obviously some of the leather guys at BF are also knife makers. I dabble in both, but sheaths are what keep me busy. Quote
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