Left overs.

[James R.Fuller]

I am not very versed in the ways of smelting, but I am extremely curious about it.

 

I have tons of cut off chunks of high carbon steel (Scraps from previous knife projects) laying in a bin to be used as spacer materials, and I was just wondering if this can be re-melted into a crucible steel. if this is possible, would I need to add carbon into it, or would it maintain its current carbon content? Something tells me I'd need to add, but I am assuming that based on the decarb that happens at high temps. I do not have any understanding on how this relates within a sealed crucible. I am fairly certain that I can reach the temps needed to do so, and I am keen to give it a go, but I only have a general understanding of the process. Any recommendations for books, dvds, websites, or even threads here on the site that would be useful, are very much appreciated. I want to make my own steel at least once, whether I use scraps or not. However, it sure would be nice to have a way to reuse those small scraps of steel I have collected. Thoughts?

[Richard van Dijk]

It has nothing to do with melting ect but a successful way to recycle left overs for me is put them in a pipe then forge weld the whole thing solid.

 

Richard

[Bret]

Never done it myself, but decarb is a function of oxygen interaction. If you sealed it with glass like I have seen done in most crucible melts the glass should melt and seal out the O2 before decarb could take place. There are probably many people here with better answers, but it should work.

 

Richard's pipe works the same way

Edited October 18, 2014 by Bret

[James R.Fuller]

I don't want to just forge weld them together. I want to do a crucible steel. I wanna try and work my way towards making my own steels, and this seems like a good place to start.

[Niko Hynninen]

Make a crucibel furnace that holds A6 crucibel. Charge A6 whit steel left overs...say 2kg.

At bottom 1" piece of brown glass 1/4 of left´s and 5 g of fine charcoal...another similar and another.

Ad top of all this 150g brown glass and put charge in furnace.

Light the furnace and run 15 min low press and look at the colour of crucible...soon as its uniform heat colour

like orange, boots gas and air flow so that you get fox tail flame form ex hole..3-4" hi.

Run 60min and use 3/8" test rod ( stainless) to feel is charge fully liquid..preheat testrod to brite orange before

you sink it trough the molten glass...glass has more viskosity than molten steel and if steel is liquid it feels bit od sens

there is not as much resintance ..if you feel solids keep running...15min test....so one.

If its fully liquid run 15 min more to get it nice and calm ...test rod will allways contaminate charge at some level..oxide, skale.

Let it cool down and remove glass at top of the ingot using chisel and hammer...not too hard.

 

Then fun starts....forging

[James R.Fuller]

Thanks, nikko! That is helpful, but how would I do this in a charcoal forge instead of gas? Same process? Because it seems like that would contaminate the charge..?

[Niko Hynninen]

You need sort of chamber for the fuel and two tuyeres at the chambers inner sides so air is

not dirrect to crucible, two tuyeres give you even heat.....so in forge this dosent work.

For fuel contamination you can use other crucible upside down.

[James R.Fuller]

Thanks! I was planing on building a furnace specifically for this.

[Niko Hynninen]

Something like this works just fine.

Inner measures 300 mm x 350mm..but for crucibel place tuyeres so they are blasting

air circular motion, opposite sides.

 

 

[Jan Ysselstein]

Niko,

 

I like the look of this furnace and its thermal mass..it might be ideal for multiple melts , if the air inlets ( I never remember how to spell tuyere ) were at an angle coming in perhaps the furnace could be used for gas/solid fuel . Maybe that would work in the current configuration as well.

 

Is the above furnace a charcoal furnace...is it slow.....does the charcoal want to fly out or create cavities below where the fire is.....do you have to keep poking the fuel down? I am assuming the crucible is standing above the air inlets by about 4 inches.

 

Jan

[Niko Hynninen]

Jan.

 

This is the very same " big crucibel" that I have had for years...but I made new body for it

So its just sheat metal jaket and hitemp cast and the crucible make inner linen of this all..

There is tuyeres both sides as you can see and they are 3" of the bottom...pic give totally different

perspective though...

Well this has bean multi purpose so far...I have melt crucible steel, smelt iron form bog ore whit this and used this as oroshigane furnace

as well..Charcoal dosent fly off when smelting or using this for Oroshigane...but if this is used to melt crucible steel I have lid for this...

You just simpy lit it and ad fuel...no need to poke fuel down...it will burn its own rate debending how much air you ad..way too much air will eat the race way in to

fuel bed but thats way too much air allready. But sens in this one tyueres are 40mm diam velosity is not hi at used air flows to greate effective empty spaces in feul bed

Crucible need to be at pedestal so bottom doset get cold.

Anyways....this works even at higher temps erosion ( wall effect) eats it every time...but its easy to repair.

 

N

[Mark Green]

Hi gang,

Here are a couple pics of my vortex, crucible furnace. It has two tuyeres, coming in opposite corners.
It is kinda oval/rectangle shaped.
I set the crucible on a 3k fire brick.

Yes, you have to feed it every couple minutes, and it does need some adjusting of the charcoal some. But, it worked great..
Last winter, I made 6 pretty nice cakes, using charcoal and coal/charcoal, for fuel.

 

 

Made of fire brick, and same clay mix I use for smelting stacks.

[James R.Fuller]

What do you use to make your clay?

[Mark Green]

The clay mix is EPK clay/ peat moss/ and sand, about a third each.

[James R.Fuller]

Thank you, Kind sir! I am hoping to try this very soon!