How Far Should I Go?

D

docmott

Joined
Dec 10, 2022
Messages
82
im new but getting the hang of it. ive made about 25 knifes. some Ok and some not too bad. Question, after I do the primary bevel how far do you cut? at first I read dont make it too thin because when you heat treat it can warp. well that hasn't happen. now im close to 1mm ? still I think its too thick. after heat treat it takes me a bit to grind down to start to sharpen. I feel I could go farther on the primary bevel to cut the time down on the next grinding thats harden. im using 1095 steel and heat treat in a wood fired forge and temper in a wood fired oven. it works! thanks for any ideas
 
Doing a search on the subject within this form it seems for oil hardening steels 1mm is probably a good safe bet. If you want to find out what the limit is grind thinner until you experience bacon edge then you will know for your situation what you can get away with.
 
Seedy Lot said:
Doing a search on the subject within this form it seems for oil hardening steels 1mm is probably a good safe bet. If you want to find out what the limit is grind thinner until you experience bacon edge then you will know for your situation what you can get away with.
Click to expand...
ok whats bacon edge?
 
An edge that looks like cooked bacon as far as straightness goes. Go too thin and you will know!!! Also need to leave room to remove all the decarb, so imo 1mm is getting close. Also depends on the length and thickness of the rest of the blade. Pocket knives vs 9" chef knives might be the same thickness, but you'll want to leave more meat on the chef to help it keep it's shape during ht.

I've been grinding typical hunting knives to about 1/16". I prefer to finish grind hardened steel....it cuts a little slower, but it cuts a little nicer for me.
 
ok what corse belt do you start with and what do you finish with? ive tried starting with 100 working down to 400 the finish with a Dimond plate, fine then ex fine.
 
I'd be considered a beginner, too, and have made a couple of dozen knives so far. So maybe my opinion doesn't count for much. But, on my first few blades people told me to leave the edge about as thick as a dime before HT. I found that to be WAY too thick. I ended up with some really fat secondary bevels! I now go down to about .5 mm. Never had any issues so far, and makes final grinding faster. Mostly 440c that I sent out for HT, but I bought my own oven this year and still no problems on 1/8 and 3/32 stock. Most recently have started using AEB-L, but grind bevels post HT. FWIW, I really like grinding after HT, maybe it takes longer but to me it feels like I have more control.
 
thats how I feel, the secondary bevels are way too fat. I can get the sharp they dont feel, or look right.
I'll try now .5 mm.
thanks!
 
This seems pretty simple, keep your edge at 1mm pre heat treat and post heat treat grind the edge to your final thickness and then add secondary. I just heat treated a batch of 52100 and kept edges around 0.030 inches pre heat treat. Yesterday post heat treat I ground the blanks to a zero grind and moved on with the project.
 
Skinner79 said:
I'd be considered a beginner, too, and have made a couple of dozen knives so far. So maybe my opinion doesn't count for much. But, on my first few blades people told me to leave the edge about as thick as a dime before HT. I found that to be WAY too thick. I ended up with some really fat secondary bevels! I now go down to about .5 mm. Never had any issues so far, and makes final grinding faster. Mostly 440c that I sent out for HT, but I bought my own oven this year and still no problems on 1/8 and 3/32 stock. Most recently have started using AEB-L, but grind bevels post HT. FWIW, I really like grinding after HT, maybe it takes longer but to me it feels like I have more control.
Click to expand...
I doubt anyone was suggesting to leave it at dime thickness and simply sharpen it.
On a recent pair, I left them at dime thickness prior to heat treat, then ground them to 0.018" after heat treat before sharpening. That's 0.46mm, close to the value you are finding to prefer.
 
Hello , 100 is a bit too fine for removing material in my opinion. I do it with 40 grit. And after I am at 90% of the final dimension i start finishing with 120 then 320 or 400. Also 1mm is a good thickness before ht. Sometimes I grind it to 0.7-0.8 (not much of a difference but still. )
 
For me it depends on what steel I am using. High carbide steels like S90V, S110V, Z-max and 10V I take to finish with the edge at .010-.015. AEBL I rough in the bevel to a scribe line and grind post heat treat. I send mine to Peters' and have not had the dreaded Bacon edge yet.
 
First time I heard about tempering in a wood fired oven. How do you hold a steady temperature for an hour or 2?? Pictures?
 
Interesting, non paying members need to use an image hosting service. A search for posting pictures should give you the right info
 
Richard338 said:
I doubt anyone was suggesting to leave it at dime thickness and simply sharpen it.
On a recent pair, I left them at dime thickness prior to heat treat, then ground them to 0.018" after heat treat before sharpening. That's 0.46mm, close to the value you are finding to prefer.
Click to expand...
Oh no, not at all. Sorry, I didn't make myself very clear, I guess. I just discovered that I could take it down much thinner before HT without any problem, and it left a lot less finish work. But on a couple of my very first knives, I did stop too soon and leave it a bit thick! Honestly, though, grinding after HT seems just as easy (to me) and eliminates the issue.
 
I'll take your word for it if you say you can hold at 400 degrees for 2 hours , but I'll be honest you would have won every dollar I had in my pocket.
 
You must log in or register to reply here.
Back
Top