Knife Part 2

[Parm]

Following from the thread below, I decided to make further progress with this knife

Knife Bevel Filling Jig

Ive been reading up on making a knife for a while now so decided to have a go this weekend. Ive gone for the stock removal method which is the easiest as a starter option. Started with a Farriers rasp that I annealed then set about filling the bevel Made this jig, shamelessly copied from the...

www.mig-welding.co.uk

once the blade was sanded to my liking I got the forge going

nice n hot for the rebar

then in with the blade

was only heating up in the middle, so gave it some welly. Got nice hot but I found I couldn’t move the blade through the heat in the middle. Forge is made from a truck rim. I need to cut a couple of slots so I can move the blade through the heat

Ended as a disaster

it isn’t a dead loss as I’ve learnt how to prepare the blade and now know that the forge needs to be modified

 

[Barking Mat]

Following from the thread below, I decided to make further progress with this knife

Knife Bevel Filling Jig

Ive been reading up on making a knife for a while now so decided to have a go this weekend. Ive gone for the stock removal method which is the easiest as a starter option. Started with a Farriers rasp that I annealed then set about filling the bevel Made this jig, shamelessly copied from the...

www.mig-welding.co.uk

once the blade was sanded to my liking I got the forge going

nice n hot for the rebar
View attachment 290558

then in with the blade
View attachment 290559

was only heating up in the middle, so gave it some welly. Got nice hot but I found I couldn’t move the blade through the heat in the middle. Forge is made from a truck rim. I need to cut a couple of slots so I can move the blade through the heat
View attachment 290560


Ended as a disaster
View attachment 290561

it isn’t a dead loss as I’ve learnt how to prepare the blade and now know that the forge needs to be modified

Every day is a learning day...

From experience we learn...

 

[Barking Mat]

Do you have long handled tongues (? Is that the word? Bit plier things?).

 

[My Old Landy]

Glad you gave it another go. I have started to make one out of a file but I have left it hard as I don't have a forge.

 

[hotponyshoes]

tongs

Rather than cut slots in the forge you could just pile up the coke a bit higher

 

[Parm]

tongs

Rather than cut slots in the forge you could just pile up the coke a bit higher

I tried that many times. The heat only remained focused in the middle

ive worked out that the blade needs to move back by about 100mm to get the tip hot. But the sides prevent this

the blade is ruined for this design. Might cut it shorter at the front then turn the melted bit into a feature

im not going to give up just yet

 

[Parm]

Glad you gave it another go. I have started to make one out of a file but I have left it hard as I don't have a forge.

How are you cutting profiling the hardened file?

 

[Parm]

Do you have long handled tongues (? Is that the word? Bit plier things?).

Yeah I’ve got a selection of those

 

[Parm]

It’s not as easy as folk make it look

 

[hotponyshoes]

You might be able to make that bit into a notch for a skinning hook?

How is the air fed into the forge? Via the base?
Might be worth thinking about running a pipe round to feed in from the side as well so it's easier to get a 'longer' fire going

 

[hotponyshoes]

It’s not as easy as folk make it look

Obviously some guys are just good at it but I reckon a lot of the videos you see on YouTube are heavily edited.
A post with a load of photos only takes a few minutes to read so it seems simple.
The last one I attempted was started at xmas and is still only 20% done.

 

[Parm]

You might be able to make that bit into a notch for a skinning hook?

How is the air fed into the forge? Via the base?
Might be worth thinking about running a pipe round to feed in from the side as well so it's easier to get a 'longer' fire going

This forge runs off compressed air.

there is a straight pipe that runs through the middle. Blanked off at one end and connected to a valve at the other so I can regulate air flow.

pipe has holes drilled along its length as I wanted a long hot zone.

hasn’t quite worked out as I planned

 

[Barking Mat]

pie has holes drilled along its length as I wanted a long hot zone.

This could be your problem.

Maybe the meat lumps in the pie are obstructing air flow.

What pastry? Will it withstand the heat ???

 

[Parm]

Found some old photos

this is the air pipe running through the middle

looks like it did give a long hot fire (ish). Will have to investigate when cool. Think some of the holes may be blocked or rusted over

 

[Barking Mat]

We have this issue with gas ovens on boats.

Gently tap the 'pie' with a hammer.

Pastry hammer ideally....

No I won't let this one go... Ha, ha...

 

[hotponyshoes]

Might be worth trying just bowing air in from the end, ie remove/shorten the pipe and just blow air out of the end of it
Light the fire by the outlet and it should blow it's way along.
You can dig a trough and set the starter along that then cover it over when its going

 

[My Old Landy]

How are you cutting profiling the hardened file?

I am using cutting discs and a die grinder. It is hard going, that is why I haven't posted any pictures yet!

 

[James1979]

Second the gas oven problem

found that in the camper van. I bought a brass brush in the end to scrub the tube with holes in with. May work?

 

[pedrobedro]

The idea with rasps is to anneal them before you shape them by heating them to red then leaving them in hot ashes overnight to cool gradually, then make the knife and quench and temper them back to a usable hardness. A gas torch is the easiest way to redo the temper and you can cover the thin edges with some fire clay to stop them burning too much carbon out of them.

 

[Blue Chips]

looks like it did give a long hot fire (ish). Will have to investigate when cool. Think some of the holes may be blocked or rusted over

Hey Parm, just a couple of thoughts: From the looks of the blade, it appears that you might have had a couple of hot and possibly oxidizing spots where you placed the blade in the coals in the fire pot, which burned the steel in a couple of places. The picture showing the pipe is somewhat fuzzy, but depending on the number, size, and spacing of the holes in the pipe, it might not be creating uniform heating in a large enough volume of the coals in the fire pot, or consistent oxidizing/neutral/reducing zones in the coals. Smooth, even, and controllable air flow is important. so you might experiment with hole size and placement, or possibly even raid the scrap bin, fire up the welder, and build a more typical tuyere setup.