Big knives

[Gerhard Gerber]

All the best for 2016! 

Just got back from a trip considerably shortened by a broken shock absorber, more to follow but here's some pics of the blade now:




I know now that a grinder belt that feels perfect and could grind a 100x 5160 blades does very little to D6 steel a few passes from new.....more later 

[Gareth]

Looking good Gerhard.

[Grathr]

That looks great!

[Sparky415]

Nice!   

 

[SAK Guy]

Nice!   

 

+1!!!

[SteveC]

That looks great!

+1 

[Etherealicer]

Shiny...

[eamo]

wow

[David]

Coming along nicely G!

[Gerhard Gerber]

Today and a bit of yesterday's work:

[David]

Thats looking great G! What kind of handle material are you think about using?

[Gerhard Gerber]

Thanks David 

For sure Micarta, but I've got 2 difficult choices to make - this knife and the course knife (will still post pics) needs Micarta.

I've got a few options in mind, hope to make 2 batches tomorrow as a start: a combo of 2 different shade blue jeans, and zombie green synthetic and emerald green wool cloth combo.
Also still want to make a piece of solid black (cotton) so I can try out an Impala horn effect and see how that works.

  Suggestions welcome!

[toolguy]

Gerhard what is the length of the blade?

It's difficult to determine that looking at the pictures.

Did I miss the length mentioned some where in this thread?

[SteveC]

Coming along nicely 

[Gerhard Gerber]

Gerhard what is the length of the blade?

It's difficult to determine that looking at the pictures.

Did I miss the length mentioned some where in this thread?

Hi

Just measured: 155mm or 6.1" 

About 70% with the 220 grit finish, if I'm not too lazy after lunch I'll work on the pommel/lanyard and the guard, everything needs to get smoothed to 400 grit and hopefully I can do normalizing and hardening tomorrow.

[Sparky415]

Thanks David 

For sure Micarta, but I've got 2 difficult choices to make - this knife and the course knife (will still post pics) needs Micarta.

I've got a few options in mind, hope to make 2 batches tomorrow as a start: a combo of 2 different shade blue jeans, and zombie green synthetic and emerald green wool cloth combo.
Also still want to make a piece of solid black (cotton) so I can try out an Impala horn effect and see how that works.

  Suggestions welcome!

 

This thread makes me want to put together my long planed belt sander 

 

[Gerhard Gerber]

I've mentioned the course I attended several times, so here's some details and a (very) few pics.

I arrived at Camp Gecko late last Sunday, before setting up camp I had to come up with a design.  I had a few already, but not being sure about the material we'd be using nothing was finalized.

During the 2 day course I witnessed the maker marking out some blade shapes on a piece of stock that an assistant grinding those out roughly.  Rene believes in not making the same knife twice except on request, and even then it won't be exact.
The man grinds free-hand, and all things considered his skills are just insane......

Anyway, I ended up with a design that was a hybrid of 2 of his knives, a blade shape I liked (with a slight drop point added) and a handle that sat very nicely in my hand, both slightly scales up.

First thing Monday morning I was given 2 pieces of mild steel flat bar, given some instructions and left to practice.  Basically did 4 bevel grinds followed by doing the tips, with each end of the flat bar shaped like a different knife.

I have no idea how long this went on, but when the results started improving I had to grind out my design from the sheet of 5mm D6.
I'd bought my first angle grinder 2 weeks before, so not had much practice yet.  The assistant (Raphael) is a seasoned metal worker and gave me some great grinding techniques & tips.

Next the blank was shaped and refined on 2 other belt grinders, also did some tweaks to the design.

Then the edge grinding started, and I don't mind admitting I was very nervous.  The resultant knife was included in the price of the course, if I messed it up at any step that was it.
Free hand this is a lot more difficult than you might expect, and the D6 is not a friendly steel.
I went through 3 belts and had to ask for help about 5 times, so the result is not 100% my own work, but at least the finishing strokes were mine.

After that came hours on hours of sanding, I was after all in the workshop of a Swiss perfectionist, and nothing but perfection will do......obtained with sand paper 

My blade was 2nd in the furnace after some more sanding the next morning, tested at 64 Rockwell afterwards.

[Gerhard Gerber]

Freely admit that Rene refined the plunge grind for me.......you have to see the man in action to believe it 
 

[David]

I'm really enjoying this thread G!

[Grathr]

That turned out great!

[Gerhard Gerber]

About 4 hours today, down to 400 grit but not perfect yet....but good enough.

Tomorrow I need to try and get my car fixed, then I'll make fire 
From research I need to normalize 3 times, then oil quench on the 4th

[Gerhard Gerber]

That turned out great!

Stay tuned....my budget is smurfed since the damage on my holiday was equal to the cost, but hopefully you can see it with a handle before the end of January 

[AimlessWanderer]

About 4 hours today, down to 400 grit but not perfect yet....but good enough.

Tomorrow I need to try and get my car fixed, then I'll make fire 
From research I need to normalize 3 times, then oil quench on the 4th
(Image removed from quote.)

Normalise 3 times? Why? Bear in mind the more times you get I up to the transition temperatures, or the longer you keep it there, you increase the chances of burning off carbon content.

How are you cooling during normalising/annealing? If you need to repeat three times you might be cooling too quickly. One way you can slow it down is to bury it in a deep steel chest (ammo box type thing) of ashes or vermiculite so that it cools down over a much longer period (12 hours or so)

Normalising is actually different to annealing, but if you're using the stock removal method rather than hot working, you shouldn't need it anyway really. If you are hot working, the normalising will undo any grain modification from forging, so you might as well just grind it  I'd anneal it, then either forge and quench, or machine the annealed blank then quench harden. I don't see any benefit of normalising as you're not going to have a gross imbalance of grain structure on something as thin as a knife.

BTW, I was told the edge should be blunt to the tune of a 1.5 to 2mm flat prior to quenching, to avoid/minimise cracking. I'm far from an expert on these matters, but thought I'd share what little I know 

[Gerhard Gerber]

About 4 hours today, down to 400 grit but not perfect yet....but good enough.

Tomorrow I need to try and get my car fixed, then I'll make fire 
From research I need to normalize 3 times, then oil quench on the 4th
(Image removed from quote.)

Normalise 3 times? Why? Bear in mind the more times you get I up to the transition temperatures, or the longer you keep it there, you increase the chances of burning off carbon content.

How are you cooling during normalising/annealing? If you need to repeat three times you might be cooling too quickly. One way you can slow it down is to bury it in a deep steel chest (ammo box type thing) of ashes or vermiculite so that it cools down over a much longer period (12 hours or so)

Normalising is actually different to annealing, but if you're using the stock removal method rather than hot working, you shouldn't need it anyway really. If you are hot working, the normalising will undo any grain modification from forging, so you might as well just grind it  I'd anneal it, then either forge and quench, or machine the annealed blank then quench harden. I don't see any benefit of normalising as you're not going to have a gross imbalance of grain structure on something as thin as a knife.

BTW, I was told the edge should be blunt to the tune of a 1.5 to 2mm flat prior to quenching, to avoid/minimise cracking. I'm far from an expert on these matters, but thought I'd share what little I know 

Hi 50

Very simple - normalizing 3 times was the general consensus from my research, but what you said makes perfect sense.  I did hotwork to get it straight, but that was minimal, the rest was stock removal.
To anneal I left the blank in (another) fire while it burned out overnight.

I don't have a furnace so for the normalizing I would need to make a big fire each time, use relatively briefly and then let it die while the blade cools......and that would happen simply on some sand.

I hope to get a big enough piece of pipe today to make a furnace in the fire, worried about burning out the carbon myself.

This is all new to me so any advice welcome 

[styx]

Can't wait to see how it turns out when you put some handles on it

[kirk13]

This is properly amazing GG! 

[bdAmmo]

Great work so far, it's turning out really well! Love the looks of that knife .

[styx]

This actually looks like it would live through the "hold my beer and watch this" parts of life

[AimlessWanderer]

About 4 hours today, down to 400 grit but not perfect yet....but good enough.

Tomorrow I need to try and get my car fixed, then I'll make fire 
From research I need to normalize 3 times, then oil quench on the 4th
(Image removed from quote.)

Normalise 3 times? Why? Bear in mind the more times you get I up to the transition temperatures, or the longer you keep it there, you increase the chances of burning off carbon content.

How are you cooling during normalising/annealing? If you need to repeat three times you might be cooling too quickly. One way you can slow it down is to bury it in a deep steel chest (ammo box type thing) of ashes or vermiculite so that it cools down over a much longer period (12 hours or so)

Normalising is actually different to annealing, but if you're using the stock removal method rather than hot working, you shouldn't need it anyway really. If you are hot working, the normalising will undo any grain modification from forging, so you might as well just grind it  I'd anneal it, then either forge and quench, or machine the annealed blank then quench harden. I don't see any benefit of normalising as you're not going to have a gross imbalance of grain structure on something as thin as a knife.

BTW, I was told the edge should be blunt to the tune of a 1.5 to 2mm flat prior to quenching, to avoid/minimise cracking. I'm far from an expert on these matters, but thought I'd share what little I know 

Hi 50

Very simple - normalizing 3 times was the general consensus from my research, but what you said makes perfect sense.  I did hotwork to get it straight, but that was minimal, the rest was stock removal.
To anneal I left the blank in (another) fire while it burned out overnight.

I don't have a furnace so for the normalizing I would need to make a big fire each time, use relatively briefly and then let it die while the blade cools......and that would happen simply on some sand.

I hope to get a big enough piece of pipe today to make a furnace in the fire, worried about burning out the carbon myself.

This is all new to me so any advice welcome 

 

Some materials do havetheir own subtle nuances, but I genuinely can't see the benefit of triple normalising here.

Annealing takes the material to a base condition anyway. You can "bump" a hardness without annealing, but there is an increased risk of cracking. Annealing is the way to go 

Throughout the roughing process, try to work both sides gradually and equally, to prevent the material pulling to one side. Normalise if you wish, but I do not see the benefit, as the quench and temper will change the grain structure anyway.

Some materials benefit from multiple tempering. Might be worth checking out for this steel. It would make more sense to me than multiple normalising. The normalising may have a purpose, but I'm struggling to figure out what

Please don't take my opinions as gospel. My experience is in the design and manufacture of mechanical components, not knife blades, though many of the principles cross over to both applications

[AimlessWanderer]

Just a note from my perspective, here I where I WOULD include normalising..... shaft manufacture...

If you are upset forging a shaft, you would be working it at high temperatures, but machining without normalising could lead to some problematic distortion. There are different sections in play, and the transitions are not uniform. There's a greater need to add an additional treatment phase to make the grain more homogenous and remove internal stresses. Sometimes proof machining then stress relieving is enough, and sometimes normalising I better.

On a knife application though, the section is essentially consistent, and I can't imagine the straightening op fighting back if it was done hot enough (or annealed after). Even if it did, you would notice distortion in the roughing stage.