How To Some Questions About Making My First Knife

[MinerDy]

Context: I'm thinking of getting into knife making, sort of as a side hobby. Not ready to spend thousands yet, but currently all the tools I'm purchasing total about $1250 which is about where I'm drawing the line.

Question 1: How can I control the temperature of the forge for HT? IIRC for preheat it's 1 hour of soaking per 1 inch. I'll be using 1/8 inch so just a few minutes of soaking. I'm going to make my first few knives out of O1 Tool Steel and a few out of AEB-L. For the stainless, I also need to austenitize for around 15 mins (or 5 mins at a slightly higher temp). This all brings me to the question... How can I hold the forge at a specific temperature to soak and austenitize?

Question 2: If I were to skip out on the preheat, would it make sense to grind my bevels post-HT to avoid warping?

Question 3: From what I understand, "Belt Grinders" and "Belt Sanders" are really the same thing, you just refer to it as what you are using it for and the type of belt. Is that correct? (and would a normal belt sander work fine for bevels?)

Question 4: What's a good HRC to aim for? (for a small pocket knife). My tempering time depends on it of course.

Question 5: I was thinking of getting some of those blue "Magnum" Sharpie's to use instead of the blue marking paint. Is this a viable option? (I don't know why they are called "magnum" either)

One more quick question: Any recommendations on type of glue to use to glue the paper sketch to the steel for cutting out? Or do you prefer just to trace it?

I'll probably have more questions to your responses in the thread but that's it for now.

Thanks for whatever insight y'all can give!

P.S. I'm quite new to knife making so don't mind me making tons of errors in the terminology.

 

[Blankblank]

Question 1, I recommend looking into steels like 1080, 80crv2 low alloy steels with not too much carbon if you insist on using a forge.

If you must use those steels, and a forge, you're going to need to use a muffle with a thermocouple (preferably) touching the blade so you can tell what temp you're at. And closely watch the entire time, also moving the blade around to keep the heat even.

2 well. So o1 in a forge will be quite a bit different from aebl. For o1 if done in a forge i wouldn't worry too much about preheating. You need to also keep in mind any soak time in a forge because the atmosphere is so much hotter than a kiln would be, is going to need to be cut down to avoid getting too much carbon in solution, and causing excessive plate austenite to form causing your blade to be brittle. I highly recommend doing a prior thermal cycle to get your blade to a pearlitic state, then heat to just above non magnetic, then quench.

Aebl, well the muffle, and thermocouple will need to be used. I wouldn't worry so much about a preheat, just try to get to austenizing temperature and soak. Try your best not to overheat.

3 yes they're the same

4 honestly I mean "aim" is one thing. Achieve is another. I say if you're anywhere above 61 or so with those steels out of a forge you're doing good.

5 it should be fine. You could even use just the black sharpie if you want.

I recommend using spray adhesive. I have loctites version. 3m has a popular one, and there a bunch of others. They work well.

Edit I'll also add that 5160, and 8670 would be a couple more options that could work alright in a forge. O1 can work, it's just easy to cause problems also. Because it's a hypereutectoid steel, you can get too much carbon in solution if overheated, or held too long. If that happens you're going to form quite a bit of plate martensite, which lends the steel to be much less tough, want you preferably want is entirely lathe martensite. So for a forge people recommend steels that are lower in carbon, and lower in alloying elements. Because you're less likely to have problems with too much carbon going into solution if there isn't as much carbon to begin with. And low alloy because, to over generalize, the more alloying elements the longer the hold time is generally (well to an extent), and you get higher chances of overheating.

Also as I said, heat treating in a forge will lead to a shorter hold time than a kiln because it's going to be a hotter environment. also, so you really can't go off of the recommendations from the steel companies, and retailers, because they're assuming you will be heat treating with a kiln generally, or in an environment that is going to be the exact heat that you want to austenitize at. So doing aebl is really going to lead to some troubles if you're doing this in a forge.

 

[Nick-D]

Context: I'm thinking of getting into knife making, sort of as a side hobby. Not ready to spend thousands yet, but currently all the tools I'm purchasing total about $1250 which is about where I'm drawing the line.

Question 1: How can I control the temperature of the forge for HT? IIRC for preheat it's 1 hour of soaking per 1 inch. I'll be using 1/8 inch so just a few minutes of soaking. I'm going to make my first few knives out of O1 Tool Steel and a few out of AEB-L. For the stainless, I also need to austenitize for around 15 mins (or 5 mins at a slightly higher temp). This all brings me to the question... How can I hold the forge at a specific temperature to soak and austenitize?

Question 2: If I were to skip out on the preheat, would it make sense to grind my bevels post-HT to avoid warping?

Question 3: From what I understand, "Belt Grinders" and "Belt Sanders" are really the same thing, you just refer to it as what you are using it for and the type of belt. Is that correct? (and would a normal belt sander work fine for bevels?)

Question 4: What's a good HRC to aim for? (for a small pocket knife). My tempering time depends on it of course.

Question 5: I was thinking of getting some of those blue "Magnum" Sharpie's to use instead of the blue marking paint. Is this a viable option? (I don't know why they are called "magnum" either)

One more quick question: Any recommendations on type of glue to use to glue the paper sketch to the steel for cutting out? Or do you prefer just to trace it?

I'll probably have more questions to your responses in the thread but that's it for now.

Thanks for whatever insight y'all can give!

P.S. I'm quite new to knife making so don't mind me making tons of errors in the terminology.

1. Short answer, you can't. Especially with the steels you've mentioned. High alloy steels and martensitic stainless steels need a proper temperature controlled oven. 01 will harden heating up to non magnetic and quenching but it really won't get the best out of the steel. Aebl you have no chance. 2 options: either buy some 1084 or similar simple steel which doesn't require a soak or send your steels out for heat treat. I strongly recommend sending your steels out for heat treat(even if using basic steel) , it is so important for a good knife and forge heat treats are sub optimal at best.

2. Most people grind aebl bevels after heat treat as its a warpy steel, pre heat or not. 01 is less warpy. Leave edge at 1mm before ht.

3. Yes they are somewhat interchangeable, however a belt grinder or linisher will generally refer to a machine designed to be used with steel. The non knife specific options range from terrible to OK. Most will make a serviceable knife with a bit of faffing. Try to find one with a defined platen edge otherwise plunge cuts are difficult.

4. Aebl does its best work when run hard. I don't use it at less than 61-62. I've not had much experience with 01 but I'd be keeping it around 60 to start.

5. Yep, heaps of people use sharpies they work great.

6. I just trace it, but have used scotchbrite 77 spray adhesive in the past, works well.

Good luck and make sure you post your progress!

 

[MinerDy]

1. Short answer, you can't. Especially with the steels you've mentioned. High alloy steels and martensitic stainless steels need a proper temperature controlled oven. 01 will harden heating up to non magnetic and quenching but it really won't get the best out of the steel. Aebl you have no chance. 2 options: either buy some 1084 or similar simple steel which doesn't require a soak or send your steels out for heat treat. I strongly recommend sending your steels out for heat treat(even if using basic steel) , it is so important for a good knife and forge heat treats are sub optimal at best.

2. Most people grind aebl bevels after heat treat as its a warpy steel, pre heat or not. 01 is less warpy. Leave edge at 1mm before ht.

3. Yes they are somewhat interchangeable, however a belt grinder or linisher will generally refer to a machine designed to be used with steel. The non knife specific options range from terrible to OK. Most will make a serviceable knife with a bit of faffing. Try to find one with a defined platen edge otherwise plunge cuts are difficult.

4. Aebl does its best work when run hard. I don't use it at less than 61-62. I've not had much experience with 01 but I'd be keeping it around 60 to start.

5. Yep, heaps of people use sharpies they work great.

6. I just trace it, but have used scotchbrite 77 spray adhesive in the past, works well.

Good luck and make sure you post your progress!

I would still love to be able to do the HT at home if possible. Are there other methods of doing that instead of a forge?

Secondly, the only reason I chose AEBL was the fact that it was a cheap stainless at relatively high quality. Are there other stainless options that could more easily be done and don't require a soak?

I'll keep you all updated.

 

[MinerDy]

Question 1, I recommend looking into steels like 1080, 80crv2 low alloy steels with not too much carbon if you insist on using a forge.

If you must use those steels, and a forge, you're going to need to use a muffle with a thermocouple (preferably) touching the blade so you can tell what temp you're at. And closely watch the entire time, also moving the blade around to keep the heat even.

2 well. So o1 in a forge will be quite a bit different from aebl. For o1 if done in a forge i wouldn't worry too much about preheating. You need to also keep in mind any soak time in a forge because the atmosphere is so much hotter than a kiln would be, is going to need to be cut down to avoid getting too much carbon in solution, and causing excessive plate austenite to form causing your blade to be brittle. I highly recommend doing a prior thermal cycle to get your blade to a pearlitic state, then heat to just above non magnetic, then quench.

Aebl, well the muffle, and thermocouple will need to be used. I wouldn't worry so much about a preheat, just try to get to austenizing temperature and soak. Try your best not to overheat.

3 yes they're the same

4 honestly I mean "aim" is one thing. Achieve is another. I say if you're anywhere above 61 or so with those steels out of a forge you're doing good.

5 it should be fine. You could even use just the black sharpie if you want.

I recommend using spray adhesive. I have loctites version. 3m has a popular one, and there a bunch of others. They work well.

Edit I'll also add that 5160, and 8670 would be a couple more options that could work alright in a forge. O1 can work, it's just easy to cause problems also. Because it's a hypereutectoid steel, you can get too much carbon in solution if overheated, or held too long. If that happens you're going to form quite a bit of plate martensite, which lends the steel to be much less tough, want you preferably want is entirely lathe martensite. So for a forge people recommend steels that are lower in carbon, and lower in alloying elements. Because you're less likely to have problems with too much carbon going into solution if there isn't as much carbon to begin with. And low alloy because, to over generalize, the more alloying elements the longer the hold time is generally (well to an extent), and you get higher chances of overheating.

Also as I said, heat treating in a forge will lead to a shorter hold time than a kiln because it's going to be a hotter environment. also, so you really can't go off of the recommendations from the steel companies, and retailers, because they're assuming you will be heat treating with a kiln generally, or in an environment that is going to be the exact heat that you want to austenitize at. So doing aebl is really going to lead to some troubles if you're doing this in a forge.

Interesting. I see most people (on youtube mostly) using forges for their HT, but maybe I'm misidentifying it. Any Kiln recommendations that won't empty my wallet?

 

[Blankblank]

Interesting. I see most people (on youtube mostly) using forges for their HT, but maybe I'm misidentifying it. Any Kiln recommendations that won't empty my wallet?

Making one yourself is going to be the only affordable option really. Even then it's not cheap, and it's a lot of work. I made my own. Was not exactly the easiest thing I've ever done. Its generally over 1000 usd for a kiln.

If you're seeing people doing heat treating in a forge its more than likely not stainless steel like aebl. And to answer the question you asked him. The short answer is no. There aren't any stainless steels that need a short soak time. The amount of chromium needed to make a steel "stainless" generally speaking causes the steel to take more time to form austenite at a given heat, to put it simply.

Please watch larrin Thomas's video on heat treating in a forge, and also I recommend reading his article about it on knife steel nerds. https://knifesteelnerds.com/2021/09/23/how-to-heat-treat-knife-steel-in-a-forge/ (you can find the video on the site I just linked also)

That should give you an idea of what the challenges of forge heat treating are, and how to best get around it. It can be done, like I said. With o1 thermal cycling before, and going into the austenization with a pearlitic microstructure can allow for you to basically just go to non magnetic and quench, taking out the guesswork.

Edit: I recommend looking into making a muffle at the very least, and getting a thermocouple if at all possible. it won't take out the possibilities of messing up, but can help your chances for success. Aebl really should be sent off, but if you are absolutely determined to do it yourself, you will not be able to do it without using a muffle and thermocouple setup of some kind. Even then it's not optimal

 

[Nick-D]

I would still love to be able to do the HT at home if possible. Are there other methods of doing that instead of a forge?

Secondly, the only reason I chose AEBL was the fact that it was a cheap stainless at relatively high quality. Are there other stainless options that could more easily be done and don't require a soak?

I'll keep you all updated.

Blank blank has said it allready, but not really. You need an accurate and consistent temp controlled kiln for all stainless and high alloy steels, and will get a better result for most low alloy steels with one over a forge as well.

I don't have an option for outsourcing heat treat where I live so I built a kiln.

Honestly don't be afraid to outsource the heat treat. Plenty of very accomplished and skilled makers outsource heat treat.

If you really want to heat treat in the forge, use 1084. While it's a simple steel It still makes an awesome knife, is cheap and readily available and can be heat treated pretty well in a forge.

 

[PMQ]

1. You can't heat treat stainless and high alloy steel in a forge, well technically you can, but 99.99% (a number I just pulled out of my butt) it's not going to be good. And a poorly HTed blade is just a waste of time and money.

2. Grind post HT can help with warping, but is going to take a toll on your tools, so it depends on how much you trust your grinder.

4. For hard use blade: 56-58, for cutting only: 60-62

5. I use sharpie because I can't find Dykem where I live