Knife number 7

Christmas is over for another year and I find myself relaxing with a few days out of the office.  Sounds like a good opportunity to finish that knife I started some time ago, but had to put on hold as other DIY jobs took priority.  The blade was shaped and hardened, but had no handle, so that has been my task for the last 2 days, followed by final finishing and polishing.

This one is a "full tang" knife, with the handle formed by attaching scales and bolsters to the sides.  The overall shape is different from any I have done before, having a gentle curve to the spine all the way down its length.  The blade material is O1 Tool Steel, the bolsters are highly polished alumunium (that's aluminum for my American readers!) and the scales are Tiger Wood, polished with lemon oil to bring out the rich natural lustre of the wood.

Dimensions are:
Overall length: 240mm (9.45")
Blade: 130mm (5.12") long; 42mm (1.65") deep; 5mm (0.2") wide
Handle: 110mm (4.33") long; 17mm (0.67") wide

What sets this one apart is the decoration down the back of the tang between the scales.  This was filed into the steel before hardening and the design is highlighted by using black epoxy glue in that area.

Another successful product in my opinion.  Now all it needs a sheath.

Enjoy the photos!

Sheath number 1

You remember knife number 6 that I finished a few months ago?  I thought it deserved a leather sheath, but with the Covid lockdown restrictions I was unable to attend a training course to learn the skill of leather working.  So, after several hours of watching videos on YouTube I decided to have a go by myself.

I used a piece of "vegetable tanned belly butt" leather and the tools from a leather craft kit I was given some months ago.  I sketched the shape onto a piece of paper, using the knife as a template and transferred this onto the leather.  Cut out the pieces with a utility knife and cleaned up the edges.  Cut a shallow groove around the edge, which provided a channel so the stitching would be recessed into the surface.

From the YouTube videos I had learned that the easiest way to stitch the leather is to clamp it in a "stitching pony".  Again, YouTube provided design ideas, so I was able to make my own out of leftover scraps in the workshop.  Sure enough, the pony did its job and the stitching turned out nice and even.  I folded over the top to form a belt loop and attached a strap with a press stud to hold the knife handle securely while in the sheath.

Once assembled I polished the leather to give it a rich, slightly used appearance.  I used this as a learning experience since it was my first attempt at leather working but having said that, I am tremendously happy with the result.

Enjoy the photos!

New Bevel Jig

Many months ago I made a jig to hold my knife blades in a secure position while grinding the bevel.  The jig was adjustable to get the desired angle of bevel.  However, over time I discovered that the jig was not accurate enough, resulting in slight irregularities in the blades.  Some others might not notice, but I did, and I was not satisfied.  So I made a new jig, stronger, more robust, more accurate and much better looking.

The original was made mostly of wood, but the new one is largely metal - a lot of aluminium with some components of brass and steel, all mounted on a wooden base.  Whereas the original relied heavily on user accuracy to ensure the blade was placed in the desired position, the new one boasts a grid of drilled and tapped holes so the blade can be secured in exactly the same orientation and angle on both sides.

The two rubber bands keep the angled front plate pulled tight up to the adjusting screw.

The ten securing holes provide a regular grid offering a wide range of securing positions.  Screws can be inserted through the holes in the tang or by pinching the edges.

The blade shown in the photo above looks scruffy because it has been hardened in the forge, but not finished yet.  When done it will be shiny silver in colour.

The base and angled front plate are aluminium, 6mm thick (0.25").  Hinges are brass and the two square tubes on the left and right sides are aluminium, 10mm square (0.4").  What are those for? ... to hook your thumbs over when holding and moving it on the grinder table.

Overall dimensions are 190mm wide (7.6"), 100mm tall (4.0"), 90mm front-to-back (3.6").

By turning the adjusting screw, the angle of the front plate will change, shown very exaggerated in the picture below, but this does illustrate the extent of adjustment that can be achieved with this design.

I am very happy with the result.  Now to put it to work ...

Knife number 6

Remember those 2 blades that I heat treated in the previous post?  Well earlier today I put the finishing touches to one of them.  Once again it has been a journey of discovery, but I am happy with the result.

I can confirm that the heat treatment was successful and the blade is now hard!  Makes me pleased I did all the shaping before hardening, because even the cleaning and finishing of the surface was fairly time-consuming, as was the final sharpening, which took a little more than 3 hours on its own.

With this one I also experimented with epoxy resin.  Several weeks ago I bought a resin kit with a selection of dyes to colour it.  (Without the coloured dyes it sets perfectly clear like glass.)  The blue/white insert in the handle is made from this resin.  In the right light it is semi-translucent and gives the impression of looking into a pool of deep blue water with a mysterious smokey haze drifting through it.

Materials and dimensions are:

• Blade - 145mm x 40mm x 4mm (5.7" x 1.57" x 0.16").  Made from O1 tool steel, hardened to ... um ... very hard!
• Handle - 110mm x 36mm x 22mm (4.3" x 1.42" x 0.87").
• Overall length - 255mm (10.0").

Handle materials, working backwards from the blade:

• Guard - O1 tool steel (same as the blade, but not hardened)
• Brass plate (0.5mm thick)
• Wood (fairly sure it comes from a tree, but I have no idea what type of tree!)
• Stainless steel plate (0.5mm thick)
• Epoxy resin block
• Stainless steel plate (0.5mm thick)
• More wood (same tree)
• Another brass plate (0.5mm thick)
• Aluminium pummel at the end

After shaping and finishing, I treated the wood with lemon oil polish, specifically suited for polishing natural wood.  Before the oil went on it was a dusty grey colour, but the oil gave it a deeper golden colour with a rich sheen and it brought out the grain beautifully.

Final step was to sharpen the cutting edge of the blade.  Another recent purchase was a little tool specifically for this purpose - see the photo.  It clamps onto the back of the blade and the guide rods slide through the slots to keep the sharpening stones at a constant angle of 17°, 20°, 25° or 30°, depending on the intended application of the blade.  I chose 25° for this one.  What you cannot see in the photo is that the clamp is exactly the same on both sides, so it simply flips upside down and the bit that is currently in the vice then points upwards so you can sharpen the other side of the blade.

The sharpening stones are graded 'coarse', 'medium' and 'fine'.  When I was happy that the edge was suitably ground down to be nicely sharp, I wrapped a piece of very fine emery paper (5,000 grit) around one of the stones and used that to polish the cutting edge to remove the fine scratches left by the stone.  It is now probably sharp enough to shave the whiskers off a walrus ... although I have no intention of testing it for that application ... only because there are not many walrusses in south Lincolnshire!

Beautiful and functional ...

For my birthday earlier in the year, I was given a gift to attend a class to learn the basic techniques of leather working.  The class was postponed because of the Covid-19 lockdown restrictions, but look forward to attending the class just as soon as the studio is open again.  I think this knife deserves a leather sheath.  Watch this space ...

Heat treating the blades

A big shout of thanks to friend Stuart, who has invested many hours over the past weeks designing and building the most fabulous quench tank in all England!  Because of its cylindrical design (bottom half of an old gas cylinder) with 3 supporting legs, it has been affectionately named "Thunderbird 3", with a nod back to the TV series "Thunderbirds" that I loved watching as a youngster.  (aka "Thunderbirds Are Go", aka "Redding Internationaal" dubbed into Afrikaans in South Africa.)  For any readers who were deprived of that childhood pleasure, this is a picture of the original.  The notable difference with my quench tank is that any flames will be coming out the other end!

This is the finished tank.  The removable lid prevents the ingress of dust and bugs while not in use and can also be used as a flame suppressor if the oil should catch fire uncontrollably (highly unlikely, but one has to be safe!)  The tank is about 100mm (4") in diameter and 450mm (18") tall, and it weighs about 140 tons!  OK, maybe that's a slight exaggeration.

Yesterday saw the inaugural launch of Thunderbird 3 for the two blades I had ready and waiting for hardening.  Decided to do this in the garage as the weather was a bit rainy and windy.

From many YouTube videos I have learned that an easy way to tell whether the metal is hot enough to harden is to test it with a magnet.  If it is still attracted to a magnet, it is not hot enough yet.  If it does not respond to a magnet, it is hot enough for quenching.  A few weeks ago I took a small magnet and mounted it onto the end of a wooden block as shown in the next photo.  The circular magnet was from an old speaker and the circular disc you see is the central iron core that protrudes about 0.5mm (0.02") proud of the stainless steel casing.  How big is this? ... just big enough to hold comfortably in your hand.

I lit the forge and tuned it to give a nice hot flame ...

"What's the W-shaped piece of wire for?" I hear you ask.  It is threaded through a hole at the back of the tang so that I can drop the blade into the oil, where it will hang suspended without me needing to hold it with the tongs.  You can see this in action in the video at the end of this post.

As the blade heated up in the forge, I removed it occasionally to do the magnet test, watching the colour change to give me a visual indicator for future reference.  Here you see the magnet test ...

When hot enough throughout, it was time to transfer the blade from the furnace ...

... into the tank ...

... avoiding the flames!

A minute or two later it was all done.  The heating and quenching process does discolour the steel, but this is to be expected.  The blades will clean up nicely after several hours of sanding and polishing.

I have attached a short video (21 seconds) showing the quenching process.  Many thanks to my long-suffering wife, Ann, for her photography skills, and for not complaining about being engulfed in the smoke cloud from the oil!

Now to get on with the polishing ...

Firing up the Forge

The knife making hobby is going well, but some time ago I thought it would be good to try using a different type of steel, specifically something that can be hardened.  After several hours of internet research I decided that "O1 Tool Steel" would be most suitable for my needs.  It combines a good balance of qualities that the knifemaker would look for - easy to work the metal, good toughness, cutting edge retention, good corrosion resistance and very good hardness when quenched in oil.

So I bought a few strips of O1.  Yes, it works well - much better than the 304 stainless steel I have used for a few knives, partly because it is not as hard when in its annealed state, and partly because it has a much lower Specific Heat Capacity than stainless.  It is this high SHC that makes it necessary to keep cooling the stainless steel while shaping it, which is a nuisance.  No such problem with the O1.  However, to make a useful, good quality blade, the metal must be hardened (not possible with 304 stainless) and for this one needs a forge, or at least some means of heating up the blade to the required temperature in a controlled manner.  At first I looked around for people in my area who have heat treatment facilities, but there are very few suitable options in convenient locations for me to get to.  And with the Covid-19 lockdown there is no knowing when we will be allowed to get out and about again.  So I wondered whether I could buy my own forge to do the heat treatment myself.

After several more hours on the internet I had found a company in Lithuania that makes a range of forges ideal for the hobbyist or professional that needs to heat treat small items in small quantities.  Customer reviews were consistently very favourable and the price was a lot lower than I had expected.  So I placed an order for one.  Shout out to the guys at "Devil Forge" - the forge arrived the day before their promised delivery date, well packaged, all the bits in tact, and the build quality appears to be very good.  It is simple to assemble, simple to use, and looks good too!

First job was to apply the "rigidizer" to the kaowool on the inside.  This is basically like a cement that you paint onto the surface of this insulating wool to give better insulation, better robustness, and prevents the disintegration of the wool.  It went on very easily and after a few days had dried throughout.

Last weekend I fired it up for the first time.  Not quite sure what to expect, I took everything outside, just to be extra safe.  Everything worked well and after just a few minutes I had figured out the optimum adjustments to control the flames to the right size and temperature.  First project was to make a pair of tongs that I can use to place things in and out of the forge.  Regular pliers would be no good, but I objected to paying upwards of £45 to buy some tongs.  Besides, this gave me a simple task with which I could learn something about working with heat and metal.  Mission accomplished all round.

Next step is to heat treat one of my blades - I have 2 ready and waiting - but for that I need a quench tank.  A friend with welding facilities has kindly offered to make one for me, so stay tuned for the next chapter.

Enjoy the photos!

All connected.  Forge and gas cylinder, all ready to go.

Looking in the "front" end.  The "back" end has a door that I kept closed for better heat retention, but it can be flipped open if heating a longer item such as a sword.

Metal heating up nicely inside.  The manufacturers guarantee that this forge can reach a temperature of 1,300 degrees C - much more than I will need!

Working the metal into shape.  My "anvil" is a section of old rail track mounted on a wooden base.

Earlier I turned a piece of the round bar to fashion a pin to connect the 2 pieces of the tongs together.  I left it attached to the end of the bar (only just), so I could hold the other end of the bar and heat up the pin in the forge, then insert it in place, snap off the bar, and hammer the end of the pin to "mushroom" out like a rivet.  It worked very nicely.

The finished item.  Now let's hope it works!

Now that's a knife!

I'm back again after a long period of silence, mostly taken up with work travels, job change and domestic chores.  However, the current social isolation imposed to manage the Covid-19 pandemic has provided some additional time at home that I have used to finish my latest knife.

I took the inspiration for the design from the "Razorback" made by "Down Under Knives" in Australia.  It is the biggest one I have made to date and is slightly smaller than the one made famous by Crocodile [Mick] Dundee in the movie by the same name.  The blade is 304 Stainless steel, polished to a mirror finish.  The handle is walnut with the guard and pummel made from brass.  I chose the walnut because I wanted the greater colour contrast between the dark wood and the lighter brass and steel, however in the photos it appears lighter than in reality.  I still have to do the final sharpening of the blade but did not want to wait any longer before publishing this post.

Dimensions are as follows (all taken at the widest point):
The blade is 185mm long (7.3") x 50mm wide (1.2") x 5mm thick (0.2").
The handle is 118mm long (4.6") x 37mm (1.5") wide x 26mm (1") thick.
The guard is 65mm (2.6") tall x 25mm (1") wide x 16mm (0.6") from blade to wood.
The pummel is 35mm (1.4") tall x 24mm (0.9") wide x 16mm (0.6") from wood to end.
Overall length is 303mm (11.9").

The hidden tang runs through the full length of the wood to provide maximum strength, but unfortunately these large chunks of metal do make the finished product fairly heavy at 570 grams (1.26 pounds).  Not a problem for me as I do not plan to carry it around.

Enjoy the photos!

I'm sure that even Crocodile Dundee would be proud of this one!

And finally, just for comparison, here are 3 together to show the size difference.

Knife number 5

Looking for a more advanced knife to make next, I am taking inspiration from a style known as the "Razorback", found online and supplied by "Down Under" in Australia.

Photo 1 below slows the rough shape cut and cleaned up.

Photo 2 shows the surface smoothed off and the two bevels ground in.

That's as far as I've got for now.  More to follow ...

Knife number 4

Back in the workshop I picked up a blade that I had started working on some time ago but then put aside because I was not happy with the way it was going.  I decided to finish it, but deliberately use it as a learning experience to try some new things.

Here is the finished knife.  It is from 304 stainless steel. The blade is 115mm long x 35mm wide x 3mm thick.  Handle is 110mm long including the guard x 20mm thick.  The guard is brass and the handle is Cedar wood, once again polished with beeswax to bring out the natural sheen and the beauty of the wood.  The Cedar is a lighter weight than other woods I have used before so overall the knife feels "blade-heavy", even more so since it does not have a pummel at the back to provide any counter-balance.

The knife is made with a hidden tang but this time I was able to drill the slot into the wood with my new extra-length drill bits.  They are 200mm long and range from 2mm to 7mm in diameter.  Just what I needed for this application but I can see I must be very careful to avoid bending them in use.

So this one is more of a working knife that I plan to use, rather than a trophy for display, but it's been fun to make nevertheless.  Enjoy the photos!

Craig's knife

Not every knife I make will be a gift for someone, but I am proud to have made this for my good friend and 'adopted brother', Craig.

Also made completely from new materials, this one features a full tang design with ornately shaped blade.  The scales are made from Bloodwood with aluminium bolsters and brass pins.

The blade is 120mm long (4.72") and the handle is 110mm long (4.33"), giving an overall length of 230mm (9.05").

Enjoy the photos!