I need some forge help! (and a bit of other help too)

[Brad Greulich]

Hello every one, I’m new around the shop here at BF but maybe you guys can help me out.

I’m trying to make my first knife, and even though I have most it planned out, I still need some help from you fine gents. My two main questions are in regards to building a gas (propane) forge and blade geometry.

Forge and heat treat

Assembling the forge won’t be a problem, but I need to know exactly what parts I’ll need. For example: will a BBQ burner work (the knife is less than 10inches total and about 3/32 to 1/8 thick so it doesn’t have to be big) and what special parts will I need aside from the pipe and burner?
Of course any tutorials or advice will really come in handy.

This is what I know about heat treating, and I know that everyone seems to do it differently so please let me know what I’m doing right, and what I’m doing wrong.

As far the hardening goes I planned on heating it up in the forge until it’s no longer magnetic (I heard that that’s a good way to tell if the temperature is right). I will do that several times and than quench the blade in motor oil (yes I’ll be prepared for a fire )

After the hardening, I was going to temper the blade in an oven at 400 degrees (can’t remember C or F but I’ll look that up again) for about an hour.

If all goes well I’ll have a hard knife at the end of it all. And please if you read this and think I’m a complete moron, please, let me know what to change/ how to do it right.

As for the geometry I planned on grinding the blade to first to a 10-15 degree angle and than grind a much shorter, 30 degree angle that will be the cutting edge.
So the question is: is this a good plan? Did I miss something important? What can I do better?

Thanks for reading this long and awkward post, and for any help you can give me during this experiential process.

 

[Dakota 11]

bbq burner not going to work, can easily build a forced air or venturi burner fot the forge burner. or can buy a set up or parts from folks like darren ellis. elliscustomknifeworks. he has parts and whole assemblies and all the refactory for the forge if u decide to make one. What type of steel are u going to use? heating to just non magnetic is easy way but not ideal way of doing. the temper is going to depend on the steel and how hard u actually got it during the harding process.

 

[sunshadow]

start by reading the "Newbies good info here " also fill out your profile info, you might be next door to a mastersmith who feels like helping out.
what is your steel? that's a starting point from which all else starts. Oh yes, welcome to BF

-Page

 

[Hmathews]

If this is your first and you don't know if you will become addicted like most of the rest of us, you might do a search on the one brick forge. They are cheep and easy to make and while a little slow, will do a good job on smaller knives. Wayne Goddard's book "$50.00 Knife Shop" would be a great help too. It covers knife making A to Z and is a good place to start.

 

[redneckswami]

I second Harry Matthews idea to get Wayne Goddard's $50.00 knife shop. I've been making knives for about 5 years now, and I still refer back to it from time to time. Great source of information! As for a burner, a really good venturi burner is not difficult to build at all, and can be made from parts you can probably get at one of the big-box hardware stores. For great, detailed information, you should refer to Ron Reil's website on building burners. Here's a link - http://ronreil.abana.org/. Ron is also a very helpful person. If you're interested in building a forced-air forge, see Indian George's tutorial, and I think that Darren Ellis has a forge tutorial on his site as well. Be warned, once you start making knives, you'll become addicted to it fast!

 

[Steinerj]

http://www.indiangeorgesknives.com/building_a_forge.html At the bottom is all the parts you need

 

[kevin adams]

and as far as darren ellis's forges are concerned if you decide to go that route,he is top notch, and the forges are great, i love mine. If you decide to go that route you wont be sorry

 

[Paul Savage]

Hey Brad , what part of ontario do you live?

 

[Kevin R. Cashen]

...This is what I know about heat treating, and I know that everyone seems to do it differently...

Yes, that is strange.

As far the hardening goes I planned on heating it up in the forge until it’s no longer magnetic (I heard that that’s a good way to tell if the temperature is right). I will do that several times and than quench the blade in motor oil (yes I’ll be prepared for a fire )

The magnet will get you in the ballpark for now, just remember there are more precise temperatures to shoot for when you advance to that point.

Why would you heat the blade several times without quenching, not even the multiple quenching guys do that. Unless you mean you are doing some normalizing steps now before the the quench. If this is the case stick to that magnet for now. It will be around 50 to 100 degrees F (your 400 is definitely F) lower than optimum, but when learning lower is better and it will make a great safety net for you. Don't fall into the trap of thinking that any heating of the steel is good for it. There are about 100 things that can go wrong with the steel every time you heat it and only a few gains to be made. With much practice and experience you will eventually find a way to balance these out, for now though better safe than sorry.

 

[jacqueeagonsr]

You didn't mention what type of steel you are using for the blade. What you have described is not a bad start for 5160 spring steel.. But, if you are using any of the fancy alloys or an air quenchable, like 440C or A2, it's a different story.
There's a good book on Heat Treatment, Selection, and Application of TOOL STEELS by Bill Bryson. I highly recommend it.
Regards,
Jacque Eagon
Eagon Leather & Knives

 

[Brad Greulich]

Thanks alot every one, for the links, and advice.
The peice of steel im using is a big question btw the way, I found it in the bush covered in rust but it looked like a good size with which ot make a blade so im figured i'd give it a try.

Yes, that is strange.

Why would you heat the blade several times without quenching, not even the multiple quenching guys do that. Unless you mean you are doing some normalizing steps now before the the quench. these out, for now though QUOTE]

The instructions I found involved heating up the blade several times, why i dont know, but the instructions seemed for the most part unreliable. so im not surprised that it is unnecessary.

thanks again for the help guys.

 

[Dakota 11]

mystery steel? wel the outcome may not be what u are really after. i now i did it also trying to learn not wanting to waste good metal, but more then likely you will be frustrated onall lvls. like i did all this work and blade wont get sharp of blade cracks or any number of events that can happen. spend a few bucks less then 20 and get a known steel then u can start down a path that will be worthwhile for the effort u put into making this blade. 1075,1080, 5160 all good to start on soem say o1 i saw no if u dont have a very tight control over temps.

 

[rocketmann]

I see that you are a cnc machinist, can you get some tool steel at work? That rusty piece of steel may not even contain any carbon!!!

 

[Brad Greulich]

I see that you are a cnc machinist, can you get some tool steel at work? That rusty piece of steel may not even contain any carbon!!!

Hmm, I never thought of that, i'll have a look at work today, if I can get anything it will probably be 8620, or 4140 (already heatreated). knowing what im working with, im sure will really help me out.