current wip

scott.livesey

scott.livesey

Dealer - Purveyor
some of the knives I am working on right now. The small blades will be paring knives although they don't flex very much. The cleaver has a handle of flowering dogwood. All the blades are 1/8" Aldo's 1084 Rc 61-62. will be making alot of small blades for a while as the muffle furnace I bought was smaller than advertised(a 6" length will fit). Many thanks to the kind folks at Wilmont
Grinders for the use of their facilities.
 
These are good first efforts but they do need some work. For one I would take the flat grind all the way back to the spine. It also looks like one of the pin holes got away from you when your drill bit flexed and wandered. My solution to that is that I have a countersink bit that I start holes with. I lay out lines on the tang to locate where I want the holes then, instead of center punching them, I find the mark where I want to drill with the end of the bit, clamp the work down, then drill the starter hole. I don't even drill even the length of the small part of the bit, maybe just past the point. That way there is more of a hole for the second full size bit to start in and I've found that I can line the countersink bit up easier than I can the center punch.

Flexibility is more of a mater of thickness than temper. How did you heat treat them?

Doug
 
Doug,
thanks for the comments and advise on holes. I just received some new centering drill/countersink bits and will try them on next batch. I also need to remind myself that drill bits are consumable and throw them out when they dull.
the knives were heat treated in my muffle furnace(thermolyne 1300), heated to about 1525, hold for 5 minutes, quench in oil, tempered at 375 for 2 hours. hardness was measured on Wilmont's Rc tester. the furnace has an analog pyrometer and manual controls, so I am still working out settings to keep temperature constant. the furnace went from cold to 1500 in about 20 minutes and took less than 5 minutes to get back to temperature after putting blades in. only problem is 6" max length, hence little knives.
i have a flat grind jig in work and will have pictures when it is up and running.
 
I'm not sure that I would austinize that hot for that long. The 1084 doesn't have the cementite that 1095 has and cementite is the easiest of the carbides to get to release it's carbon. I would either reduce the austinizing temperature to around 1450° or decrease my soak time to just long enough to make sure that the steel is heated evenly throughout. I know that you are making kitchen knives which aren't going to be used to chop wood or split the pelvis on a deer but HRc of 61-62 seems a little hard to me. It's easier to sharpen a blade than it is to grind out chips in the edge. I would bring the temper temperature up by 25° and shoot for an HRc of about 58-60.

You're right about drill bits being consumables. I found a hardware store in my area that sells fractional drill bits in packages of 10 and I purchase my must commonly used sizes that way.

Doug
 
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