Making fixed blades, using files etc. lessons learned

[dks]

I decided to try making some fixed blade knives.



I followed guides from the internet and learned a few things along the way.
I saw two old metal ? files at a car-boot sale that seemed good for my project. I could have also used leaf springs.

Older files and springs are usually made, totally, from high carbon steel. They are quite hard and need to be softened, so that they can be worked on, and then hardened again to the desired hardness, so that they can keep an edge, whilst not being too brittle.
One file was a fine one, with a thick body and the other a rougher one, possibly for wood.
My first step was to test if they were made wholly from high carbon steel, or if they only had it on the outside.
I used my bench grinder to remove some of the outside steel and checked the sparks being produced by the outside and inside parts of the files. A nice, tree like spark, from the whole part of both files showed that they were made from only high carbon steel. If you get long, straight sparks with only a bit of branching at the end of it then you do not have high carbon steel.

The next step was to soften the blade.
This was to be achieved by heating the blade to a red hot colour and then checking to see if it stopped being magnetic. Once that happens you let it cool down slowly and it softens.
Following some advice from the internet and assuming that it would be easy I decided to use a blow torch to heat the first file.
This was a waste of time as, despite doing the whole thing in a warm area, away from a breeze I only managed to get one small part of the file red hot and non-magnetic.





I assumed that I had softened it a bit and after 1 hour gave up, let it cool down and started to work on it.

Because I was using power tools I was able to do nearly everything that I wanted. I only realised that the file was still hard when I failed to drill holes through, for the handles.

First I drew the shape I wanted on the blade. (I was going for a clippoint shape).



Then I used a cutting wheel on my angle grinder to remove most of the metal I did not need..





And the bench grinder to shape the blade, smoothen it and remove some of the files teeth.



Then I used a belt sander, with coarse sandpaper to remove most of the teeth and shape the blade.
Though I started with a rougher sandpaper I found out that smoother, 120 Grid, worked better and was more controllable, as it did not make the blade “jump”. I used high speed.



I marked the point at which I wanted the edge to start, so that I did not grind more metal than was necessary (once you grind a bit you get a step where your blade should stop so it is easy not to make a mistake)
Notice the failed attempts at drilling the handle…





I also set the bevels and the final, general edge, easily, with the belt sander. I found that by having the point of the edge facing the direction of the belt movement I was able to better control the blade and shape the final edge.

To harden the knife (which was still hard..) I used a charcoal fire.
I used it to harden my first file/knife and to also soften the 2nd one.
I also used the same process to later harden the 2nd knife.
The process was surprisingly simple. You light a fire, put the files in and use an electric air pump to boost the fire. I realised, during the 1st attempt, that the pump and me were getting too close to the fire, so I attached a pipe to the mouth of the pump, keeping me and the pump at a more comfortable distance. (pictures from both efforts)

Air pump. You need a high volume, low pressure pump, like the one used for inflating toys. A hairdryer will also work. See the attached pipe.



Blowing, Glowing





Checking if it has gotten non-magnetic.



Once the files/blades are at the non-magnetic, red hot stage you have two options:
If you want to soften the blade you let the whole fire die down, with the blade, and get your cool, soft blade out the next day
If you want the blade to harden you need to cool it quickly by dipping it in a liquid. Most people suggest some sort of non-flammable (easily) oil or water. Water cools the metal faster and makes it harder, but you run the risk of cracking. I used a big bucket of water as I did not have any oil I did not need.
You need to be quick and immerse the whole blade to avoid warping
Out of the flames and into the water.



After this stage you will have a very hard and brittle blade.
You need to temper it, making it a bit less hard. For this you can use your oven and bake the blade for 2 hours. The higher the temperature the less hard the blade will be at the end. I used 300Celcius, as that was the hottest my oven would go to. This temperature provides a reasonably good compromise between hardness and brittleness. You then let the blade cool down in the oven.



The next stage is polishing the blade as it will be a nice dark colour after the whole process.

I used the belt sander for a bit of cleaning, though I liked the dark colour the blades had.
The next step is the handles. I went for the simplicity of full tang. I used the wood from a new small axe handle which I cut in two halves lengthwise. This spared me the gamble of using unsuitable or wet or soft wood.



For the 1st knife, since I could not use pins as I could not drill the metal I cleaned it thoroughly and used strong epoxy glue. I applied pressure to the handled and let it set, clamped for half a day.



For the 2nd knife, since I was able to soften it properly and drill holes I intended to use epoxy and two pins. I also wanted to leave a large lanyard hole… . Ideally I would have used corby style rivets or chain bolts or something similar but I was not able to find any… maybe next time.
I went for a traditional, butcher style blade. I did not remove all the file teeth from the sides as it would have made the blade too thin, and, they looked nice.





The only pins I could find were “spring” pins that you hammer through the material.



I really should have hammered them first halfway through the tang and then put the wooden handles on, but I put the epoxy on and tried to hammer them through the wood and then the metal..
So, since from what I realised I missed a hole by a bit, a part of the metal handle snapped because of the hammering . Thus , since everything was covered in epoxy I just had to glue the handles, with no pins, and lose about 4cm of the total length… and have nasty holes in the handles.



I filled the holes with putty later.
I then used the belt sander to shape the handles of the knives and a combination of stones/Lansky/Belt sander to get the final edge.
For the handles I used varnish on the clippoint one and teak oil on the butcher style one, to see what they looked like.
Before varnish (the handle was designed for right hand use)



After varnish (two coats, clear wood varnish)




And before the teak oil:



And after.




Here you can see the bit that broke off, at the top right, covered in glue...


The clipoint was given to be used for some hard work, in a farm, but I still have the butcher style (straight back) one, which will go in a car.

I tested the hardness of both knives (scratching) and they feel hard enough, whilst still being a bit flexible)

OK, the important parts:
The whole process was easier than I expected.
Mass produce – anneal and temper many blades at the same time as it saves time.
Use charcoal not a gas torch (I also used the charcoal for a barbecue later)
Get good quality materials and have them ready
Use power tools.
Do not hammer on a hardened blade…
Take it slowly when grinding.
There is no hurry between any of the processes really.. I took a break of two weeks between steps
Protect yourself
Plan ahead what you will do and mark your metal accordingly.
Get some proper rivets.
Find some files with very short teeth (the smoother the better)

If you want a good looking knife got to Seved 

[ducttapetech]

Very nice write up. Nice looking knivies too.

Nate

[dks]

You have to love the utilitarian look   

[Grathr]

Great read!
The knives arent pretty, but they look like a solid pair of users


Sent from a device made from star dust using tapatalk

[dks]

The second one would have looked like a nice machette/camp knife had I not broken a bit off and been left with 3 useless holes on the handle. 

Next time I am making a biiiiger knife, so that I can afford to break bits off.

[kkokkolis]

Very nice.
Are you aware of the Greekblades forum?
The site's owner and aknowledged knife maker, Nickolas Dontadakis, died suddenly and the site is since then not that active, but it contains a lot of info and is oriented to the Greek word.

http://www.greekblades.com/index.php

[dks]

I was not aware of the forum. 

I will read through it.

I have some knives from Crete.

[Sparky415]

I know how many hours this kind of thing takes 

Great work Mate   

[dks]

It gave me an excuse to have barbecues, justified my tools, allowed me to hide in my workshop...
Next time I will be better prepared and anneal more blades at the same time.... now I need some rusty files to give them a new life...

[AimlessWanderer]

Nice work, both on the knives themselves and on the write up 

If I may, I'd like to add a few tips from my own experience 

Materials:
The most common high carbon steels that people make their own knives from are O1, A2 (difficult) and W2. The key here is the letter ...

O = Oil quench
A = Air quench
W = Water quench

... and old files suitable for knifemaking will generally be made of W2 ... so you did the right thing with a water quench. Using the wrong quenching medium for the wrong steel will lead to problems, so you can generally stick to using water with old files. Don't try to get clever by oil quenching a "W" steel, or water quenching an "O" steel, unless you REALLY know what you'r doing as you'll create problems and possibly destroy the workpiece.

Annealing:
Always anneal the blade before working the steel. Get the steel up to the correct hardness as quickly as possible, and transfer to a box of vermiculite to let the steel cool down as slowly as possibly. Don't leave the steel in the heat for any longer than necessary though, as this can burn off carbon and reduce the hardening potential. I thicker lump of material will need a slightly longer "soak" time though, to ensure the temperature is above the critical level throughout the workpiece. Allow to cool fully before breaking out the drill, grinders etc

All heat treatment should be done from this base condition. If you screw up the hardening - reanneal it before attempting to quench again. If you try to harden something that has already been partially hardened, you greatly increase the risks of cracking.


Pre-machining:
On your initial shaping/grinding operatrion, try to leave about 0.5 - 1mm on all surfaces. Aim to leave yourself a flat spot of about 1.5mm wide at the cutting edge of the knife. The reason for this is that when you temper a knife, the thinnest sections could temper more, leaving you a hard knife with a soft edge. 

This is why new axes/knives are sometimes quite poor, but get better after they've been sharpened a few times. All the soft material is being removed to get to the good stuff underneath

Hardening:
Reheat the steel back to the critical temperature and quench carefully in the correct medium. Note, with oil quench steels, it works better if the oil is fairly hot to start with - drop the steel temperature too low too quickly, and your knife could quickly become a jigsaw puzzle. With water quench this is not an issue

Tempering:
In order to restore some ductility and toughness to the steel so it isn't brittle, I think you ned to be going a bit hotter than your oven will go. If you cannot achieve or control the required temperature, you could try just quenching the edge of the blade (maybe to 1/3 the total blade height) to arrest the chrystaline growth at the edge, and then leave the knife to cool at room temperature. The residual heat in the spine of the blade will provide sufficient heat to anneal the hardened areas (this is kind of what they do with Khukris)

Finish grind as required, and post lots of piccies on MT.O 

Aside from that, all dks's points and summaries are spot on 

[kkokkolis]

A  couple of great Greek knife makers for inspiration and eye candies.

http://www.gunandknifeclassics.gr/index.php?option=com_content&task=blogsection&id=5&Itemid=54

http://www.alkiviadisknives.com/

http://www.cretanknives.gr/products.aspx?id=4&page=1&pagesize=7&srt=1&srtd=1&cat=4

[Mr. Whippy]

Thank you guys for posting this up. 

My wife gave me a forge for Father's day and I've been wanting to try this myself.  I'm always better off reading what someone did rather than a dry manual.

 

[dks]

You can always tell who comes from a region with a knifemaking tradition    What do you suggest I do with leaf springs?

I used this guide from Sandvic and 300C looked like a good temperature for tempering



http://www.smt.sandvik.com/en/products/strip-steel/strip-products/knife-steel/hardening-guide/purpose-of-hardening-and-tempering/

It will good to have  a forge But the air pump worked prety well too. 

[AimlessWanderer]

You can always tell who comes from a region with a knifemaking tradition    What do you suggest I do with leaf springs?

I used this guide from Sandvic and 300C looked like a good temperature for tempering

(Image removed from quote.)

http://www.smt.sandvik.com/en/products/strip-steel/strip-products/knife-steel/hardening-guide/purpose-of-hardening-and-tempering/

It will good to have  a forge But the air pump worked prety well too. 

25 years in engineering, and three days getting one on one tuition from a knife maker  I've picked up a few things along the way, but don't consider myself an expert with this, by any stretch of the imagination

My mistake on the tempering temperature, I thought it should have been nearer 400-450, but I might be getting cross hobbled with other facts and figures  For a double check, see if you can find a tempering range online for W2. If that's on par with the other data, then stick with it  I just don't want you putting all that work in for it to crack on you 

As for leaf springs, that's what Khukri's tend to be made of, so I'd stick with water as all they do is hold the knife with the cutting edge upwards and pour water over it  If you have enough steel, try a partial quench on one and a full Q&T on the other. Not knowing how the actual chemistry compares and what any variations would lead to, I'm not certain which would give optimum results

[dks]

I found this, with regard to W2


http://www.bladesmithsforum.com/index.php?showtopic=8259

Maybe you were thinking in terms of Fahrenheit. 

I assume that the sandvic guide may be pretty general.

I would try and work with a leaf spring, mainly because I will not have to remove so much metal from the sides, like with the files's teeth. 

Many thanks for the advice. 

[Mike, Lord of the Spammers!]

That's a great tutorial mate, thanks for sharing

Sent from the astropathic choir.

[dks]

It is nice to see people learn from my mistakes 

[Noa Isumi]

Great job on your first knives. They look good.
I think nearly everyone starts out with a file or an old saw blade. I still have my first file knife packed away some ware, 20 years later and still no sheath. 

One of the best books for beginners is Wayne Goodard's "50% knife shop" from Kraus publications. I cant say enough about this book. Well written with tons of illustrations and photos showing not just telling the how to of knife making. That was the big problem with the blacksmith resurgence of the 80's and 90's was most only had Alex Bealer's "Art of Blacksmithing" to start, and although quite possibly the best general and historical how to of its day it is dry and has very few illustrations and little hammer technique making it difficult at best to produce results. but it is still a must read for smiths.

Goodars's book is available from bookstores like Amazon
http://www.amazon.com/Wayne-Goddards-Knife-Shop-Revised/dp/0896892956

or as a online Pdf
Wayne Goddard's 50 Dollar Knife Shop-Origional Edition-PDF

http://www.ebook3000.com/Wayne-Goddard-s--50-Knife-Shop_95135.html

It is written from and expanding on a series of to articles he wrote for Blade Magazine back before the Tacticool revolution ruined most sporting magazines.
I'm not a "Fudd" I just think too many Arm Chair Rambos(ACR) marketing garbage to other ACR's has become sole point of these rags. Just like Popular Mechanics is nothing but car and home theatre adds now and the how to's, plans and tips are all gone, or Mother Earth News is now all commercial products and political eco propaganda rather than homesteading and independence. But I digress. 

Here's a thread I found from the Blades And Bushlore forum with a few other knife making books.
http://bladesandbushlore.com/index.php?topic=8424.0

As for the heat treatment at home jobs with unknown steel lead to a best guess senario. It will never be spot on the way a pro with a known steel will be. But with luck and care you can still get decent results. You learn through trial and error, I have broken many blades, redone soft ones and warped large ones. Even pro blade smiths mess this up sometimes, just watch Man At Arms on youtube, both Tony and the Stagmore Bros have had to fix bad HTs and they are major sword smiths.
A set of hardness test files is a good idea for the hobbyist doing  home heat treat as they are way to tell you RC value that doesn't cost a fortune like an actual test machine.

[dks]

Many thanks. The fist thing I though after finishing was that I have no sheath. I have to see what I can make..
I can see myself reading more on this.
The problem is that with scrap/used material you never know what the steel really, how it was used/abused.

I also would like to keep the whole process simple, with some basic steps that work.

[AimlessWanderer]

I found this, with regard to W2

(Image removed from quote.)
http://www.bladesmithsforum.com/index.php?showtopic=8259

Perfect! 

Maybe you were thinking in terms of Fahrenheit. 

I assume that the sandvic guide may be pretty general.

You may well be right 

I would try and work with a leaf spring, mainly because I will not have to remove so much metal from the sides, like with the files's teeth. 

Still leave yourself that envelope of steel to be removed with the linisher after treatment, especially the dull edge, so you bring the good steel to the fore 

Many thanks for the advice. 

You're quite welcome mate. There's an incredible wealth of wisdom on here, it's nice to be able to throw something useful into the pot occasionally   

[Noa Isumi]

my first sword attempt was made from a truck spring. When about part way through I took a heat and struck it and it just crumbled under my hammer like safety glass. 
On closer inspection a 4in section in the middle was spider webbed with stress fractures that opened up under the heat and my straightening the spring.
now I buy new springs and cultivator tines and blades from Tractorsuply, or drive into the city to the  Knife Makers Supply. Im lucky to live near a Knife shop.

Yes remember to leave material for final grind after HT to remove decarburized metal and any scale pitting and allow a good edge.

Goodard's book does have a chapter on basic home Heat Treat

[dks]

rotavator blades  sound like a good idea. I have some broken ones somewhere, but maybe new ones will be even better, if the cost is reasonable. I do not remember how much they are now.
The ones designed for rocky ground are straighter and may work well for smaller knives.

Thanks to all.

[dks]

Continuing my search for a screw system, suitable for securing handles, I found and bought these connecting screws, used in cabinet making. Not pretty but you end up with the same look on both sides and they are pretty solid.

Here is an example of the type of product from Amazon for your reference.



http://www.amazon.co.uk/KITCHEN-CONNECTOR-BOLTS-SCREWS-HOLE/dp/B007V2GZ0E/ref=sr_1_2?s=diy&ie=UTF8&qid=1415206742&sr=1-2&keywords=connecting+screw

[Noa Isumi]

Saw screws work well and tend to be a little shorter, so less to cut down. Plus they have that classic hand tool feel.



Here's the website to my local knife makers shop. I don't know if they will ship overseas but you can get idea for some types of hardware to look for.
http://www.texasknife.com/vcom/index.php

And here's a couple more of the bigger catalog/online services that can be fun to look at. I have not dealt with most of these sites. This is just part of a Google result list im putting up since I know international versions of websites/searches can differ.
http://usaknifemaker.com/
http://www.knifemaking.com/
http://www.hawkinsknifemakingsupplies.com/
http://www.knifekits.com/vcom/index.php
http://www.knifeandgun.com/

[dks]

Not even amazon.uk will post these to me.

The shipping cost can also be stupidly high.

I went through all the DIY/hardware stores and all I could find were these, at one store. Even cabinet makers use the plastic headed ones now.

I will check the bike shops too as they seem to use some similar style screws for the chains.

All in all I am happy with my find.

I also got some cobalt drill bits for my folding knife, SS, projects.

[Higgins617]

Not even amazon.uk will post these to me.

The shipping cost can also be stupidly high.

I went through all the DIY/hardware stores and all I could find were these, at one store. Even cabinet makers use the plastic headed ones now.

I will check the bike shops too as they seem to use some similar style screws for the chains.

All in all I am happy with my find.

I also got some cobalt drill bits for my folding knife, SS, projects.

Bike chains have pins holding them together, fairly small ones at that so I don't think they'll be able to help you out. Unless you guys have vastly different bikes?

[dks]

I am thinking of these chain ring bolts.

I have seen them mentioned for knife making in some threads, depending on their size:
http://www.chainreactioncycles.com/cy/en/chainring-bolts

I assume they will be available.

[Higgins617]

Ohhhhhhh I gotcha, good idea. Sorry I misunderstood you, didn't want you to waste the trip

[Noa Isumi]

The shipping cost can also be stupidly high.

ouch!!
Just checked your shipping costs to see just how bad; 168usd for a 5x5x3in 5lb package From Houston to Nicosia
Its been a few years since I worked a shipping dock so I guess I forgot how ridiculously expensive international can be. I would not want to inflict that on anyone...
But then again I did once mail 2 bags of potato chips 1500mi to my sister when she was pregnant and it cost close to 60usd. She was driving her husband nuts with a craving for her favorite chip from back home.
.

And so I say good luck  localy with your searches. And those bolts do look interesting