At what thickness do you…

Bühlmann

Bühlmann

North Lake Forge
Joined
Jan 6, 2022
Messages
475
….grind your bevels entirely post-heat treat?

I’ve only made a few blades, but I’ve only ground bevels pre-HT. I’m working on an .080” stock design and am concerned about warpage if i grind pre-HT this time, as it’s the thinnest stock I’ve started with.
 
It depends in part on the steel. I've ground up to 5/32 with AEBL post heat-treat. However to date AEBL is the only stainless I've used. Carbon steels I generally grind pre-heat.
 
I neglected to mention that. I guess I thought it was a more general question, but I see now how the steel would affect the answer. I’m using 15n20 for this one.
 
Bühlmann said:
I neglected to mention that. I guess I thought it was a more general question, but I see now how the steel would affect the answer. I’m using 15n20 for this one.
Click to expand...
I haven't used 15n20, so I can't comment on that. However it's a common steel, so I'm sure you'll get some answers from others on here soon.
 
Bühlmann said:
….grind your bevels entirely post-heat treat?

I’ve only made a few blades, but I’ve only ground bevels pre-HT. I’m working on an .080” stock design and am concerned about warpage if i grind pre-HT this time, as it’s the thinnest stock I’ve started with.
Click to expand...
If it's not forged, I dont grind prior to heat treating. It not warping is a big part of it, but also if I'm plate quenching, it allows the whole blade to be clamped between the plates and get much better contact.

Some say that it won't make that big of a difference, but I want to be extra sure I'm cooling the whole thing, especially the area around the edge, which would be the parts that aren't going to touch the plates if I grind before the heat treat.
 
Cliff has the real answer in his post .... WET GRINDING.
A simple Kool-Mist system or a cheap Chinese clone of one will make grinding hardened steel much easier and get a much better finish without risk of damaging the temper on the edge. Using the actual Kool-Mist 77 or 78 lubricant additive is absolutely worth the cost. A gallon of concentrate will grind a LOT of knives. It works out to pennies per knife.

With the magnetic mount you can easily move the spray from grinder to grinder or to the drill press or bandsaw. Drill bits work better and last longer when lubricated and cooled.
Attaching an appropriately placed 2"X3" steel plate to all the tools you want to cool will allow a fast and easy move of the spray nozzle from machine to machine.
 
I grind everything post HT other than if I’m working with a shallow hardening steel and going for a hamon. I use a misting system now and it significantly reduces grind time and stress. I can grind an entire blade without dipping it in a water bucket once. It cuts my grind time almost in half.
 
I'm grinding most things post heat treat currently and just this week added a mist system. I've seen it said in other posts (older posts) that you can get by with 30psi but I did just see a post earlier this year where Stacy says that people with gunk buildup are most likely not running it at a high enough pressure. I have a 27 gallon compressor that max's out at 150psi. I know this is way more than I need but where should the sweet spot be? 80psi? 100psi?

I'm currently working with heat treated AEB-L (61-63) and MagnaCut (61-63).
 
mooniesdl3 said:
I'm grinding most things post heat treat currently and just this week added a mist system. I've seen it said in other posts (older posts) that you can get by with 30psi but I did just see a post earlier this year where Stacy says that people with gunk buildup are most likely not running it at a high enough pressure. I have a 27 gallon compressor that max's out at 150psi. I know this is way more than I need but where should the sweet spot be? 80psi? 100psi?

I'm currently working with heat treated AEB-L (61-63) and MagnaCut (61-63).
Click to expand...
I run my compressor between 100-120psi for my mister and it keeps a lot of the mess down. Not sure if that’s the best range but it’s what works for me. Keeps blades completely cool for the entire beveling process.
 
Stacy E. Apelt - Bladesmith said:
Cliff has the real answer in his post .... WET GRINDING.
A simple Kool-Mist system or a cheap Chinese clone of one will make grinding hardened steel much easier and get a much better finish without risk of damaging the temper on the edge. Using the actual Kool-Mist 77 or 78 lubricant additive is absolutely worth the cost. A gallon of concentrate will grind a LOT of knives. It works out to pennies per knife.

With the magnetic mount you can easily move the spray from grinder to grinder or to the drill press or bandsaw. Drill bits work better and last longer when lubricated and cooled.
Attaching an appropriately placed 2"X3" steel plate to all the tools you want to cool will allow a fast and easy move of the spray nozzle from machine to machine.
Click to expand...

I've been using a Kool Mist knock off for a while now with plain water, not the additive, but I've been wondering about potential long term rust damage to my grinder parts, especially moving parts like bearings. Does the additive help with that? Is this even something I should be concerned about?
 
Oops, forgot to answer OP's question too!

I grind all my knives post HT, regardless of thickness. But I also don't really make big beefy knives. If I were to make a thick 1/4"+ kukri or something I would grind a lot of it before HT.
 
HT piece of steel from which you want to make knife ........ceramic belts don t give **** which steel is in question , they will eat it fast !
hJ1YrWk.jpg

Cut and shape knife from that
GGu4bSV.jpg

drill holes for pins
wE0xZux.jpg

and grind bevels ..........
Z52WxXo.jpg
 
You must log in or register to reply here.
Back
Top