How sharp should the blade be before sending it off for heat treating?

M

MilesManf

Joined
Feb 28, 2016
Messages
8
First post on the forum and I have a newb question. I recently took up knife making ( stock removal ) for now.

Im finally finishing up some of my blanks after a few days toiling with saw and file. Fast Forward to today im getting ready to put the bevel on How much of an edge should I leave on the blade before heat treating?

Thanks all!
 
Hi Miles (welcome!) - I am having the same thoughts. I have just sent my first balades to HT. Given the fact that I grind them manually (no belt sander around, just a jig to help to keep the file under pre-set angle - like an oversized EdgePro) I ground them to 0 edge (lack of precision, not intention). I got feedback from the person doing the HT that the edge should have a few tenths of milimetre (0.1 - 0.2) thickness. I understand that there are surface effects taking place while HT and you may loose a little from the edge if you send the knife for HT 'sharp'.

But I am also hoping for a reply from experienced knife makers.
 
Not very experienced, but it depends on the blade, steel & what your HT says to do. Some steels are easier than others. I was told that .015" was good for the D2 I just sent in, & had no trouble with it, worked out very well, but that's D2. Other types of steel can end up with the "crispy bacon" quench. Ask the HT & just do what they say.
 
Thank you for the welcoming! I will consult the HT company. Is this the correct thread If I wanted to post progress pics and look for criticism?
 
i use 1095, 1084. i go with .025. i have encountered "bacon edge" (warp) heat treating a .018 edge.
 
I usually quench at about 0.03". But that's doing my own heat treat. If you're sending it off you could probably get away with less...
 
Thanks Woodster, I am using 1095 for my first batch of knives. Im doing a couple at a time so I dont have to delay my trial and error. Good looking knives BTW!
 
I work with stainsless that gets HT-ed professionaly.
I go for 1/3 to 1/4 mm pre HT
 
In a video ( (abound finish-sanding a blade) from Aaroun Gough he only re-finishes the blade with grits 600 and higer after HT. No beveling work at all apart from final sharpening. So his bldes must have been much thinner than what most folks here would suggest. But the blade was a stainless steel and he does his own HT. I would just conclude that this is very much process & steel dependent value (thickness of the edge before HT, that is).
 
You do two things after HT.
1) Regrind/sand to remove the oxide layer that forms during HT. If HT-ed without oxigen you can use very fine sandpaper for that (I've done 2500)
2) You form the actual edge. You have a blade with an edge that is thin but not sharp. You then put on an edge 2x 20 degrees (or what angle you choose) and have the actual cutting edge
 
I've sent mine to Peter's at around 0.01 and haven't had much trouble. The only one that got bacon edge was a hollow grind that I could see bend when I pushed from behind with my finger.
 
Hengelo_77 said:
You do two things after HT.
1) Regrind/sand to remove the oxide layer that forms during HT. If HT-ed without oxigen you can use very fine sandpaper for that (I've done 2500)
2) You form the actual edge. You have a blade with an edge that is thin but not sharp. You then put on an edge 2x 20 degrees (or what angle you choose) and have the actual cutting edge
Click to expand...

Copy that. Thanks. My blades just came back from HT (look good at first). This advice has perfect timing.
 
You must log in or register to reply here.
Back
Top