Experiments in grinding

[Jbh blades]

Good Day Dogs and Lady Dogs. You may have seen my other post about temper finish but I'd like feedback on these two experimental knives. They're my first full flat grind and my first time trying distal taper (I'm pretty new at this so please correct me if I have any terms incorrect). They're also my first skeletonized handles. I've made 4-5 knives out of files in the past and they seem to harden properly and hold a great edge (An old machinist friend gave me a large stack of old Nicholson files before he retired). Also If you'll notice I have some spots on the blade after heat treat and I'd like your insight on what is causing this. Being experiments, I did not finish them out as I normally would have. I was working on a knife for a friends birthday at the same time I made these so I focused most of my time on his knife. Thanks in advance Guys!

JBH Blades
Bryce Hancock

 

[Wayne Bensinger]

Pretty cool look, I like them, different. Out of the box! One question, in order to drill the file material, must you first anneal it then re-harden it when your machining is done? Thanks for the insight.

Wayne

 

[Jbh blades]

Yes sir, I have always annealed files prior to grinding/machining. My new kiln will make this easier to do without warping the files. I heat treated these blades in the kiln. I've been using a converted bbq for annealing and heat treating thus far (got the evenheat 2 weeks ago). Just used my new KMG for the first time to profile a blade. Oh man, thats one nice piece of equipment!

 

[Doug Lester]

My best guess at the spotting is that they were not absolutely clean when they were put if the oven to temper. Try cleaning all oil off them the next time you want to try this with something like acetone then handle them with rubber gloves as you put them into the tempering oven.

Doug

 

[rhinoknives]

They look like usable knives. The distal tapering job is fine. It's hard to tell the exact size of an edge you are going to but I suggest you go to 0.20 or less or just go to zero at the edge with your FFG and then sharpen. Thin is in!

Now its time to make another and fix the problems that you already see!

 

[Jbh blades]

Thanks for your replies gentlemen. I'll try acetone next time. I have been washing the blades in warm water and dish soap, thoroughly dry and coat in ATP-641. Let completely dry overnight then into the kiln. I was wondering if the spots were from tiny holes in the ATP? I ground the edge to .027 on both of these pre HT and just hand sanded a little between temper cycles. I was worried about edge cracking during quench although I quenched in heated veg. oil (water/brine more likely to cause edge chipping I've read). I've carried one of the knives for a couple days now, Its cutting pretty well and retaining it's edge.
And yes Laurence, I've started another. I think I may have a problem!

 

[wall e]

Hot water and dawn dish soap. Hot as it gets warms the steel and makes the water evaporate faster. We scrubbed M60s with shaving cream,carb cleaner and hot water after using blanks to get the barrels shrome bright again.