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Hi all i just wanted to share my setup, i have been using a modified 4kg Devil-Forge Furnace with a refractory upgrade along with a zircon based refractory coating thats manufactured in Australia by a company called Mathew industries. (I was told numerous times that it couldn't be done and to only use diesel)
The Ingots/Puck i have been making are around the 800g mark give or take 50g in a number 2/2kg crucible. mostly within the 1.60%c range.
Forgive me i will have to take some pictures and upload them later on in the day, as im on my laptop (used for google and YT primarily.

Jacob Christian has reacted to this post.
Jacob Christian

here are some pictures

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Jacob Christian has reacted to this post.
Jacob Christian

@ajfmetalworks Oh dang you are not even using a blower on that thing! Definitely impressive!

Excellent job, I had actually messaged Devil-Forge based out of Lith on Etsy and they said their furnace can't melt crucible steel. Which one of the two furnaces are the ones you used for the 2 kg ingots, was it the faded black/rusty smaller furnace or the larger one?


Have you considered adding a blower into the system and modifying that into it? Also did you buy the insulation without the refractory already pre-installed and just install it on your own?


I'm in the process of trying to set something up myself and Jacob was kind enough to refer me to this forum, and sent me some valuable material I've been going over. Never fabricated before so I'm excited to make this, along with building a new anvil stand for my two anvils, my first fab project.

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Jacob Christian
ABS Apprentice Bladesmith. Documenting my journey bladesmithing and sharing my interest in Indo-Persian antique blades and Wootz steel! ⚒️🗡️

Yeah absolutely no blower at all, i have never found the need to add one, i can get to temps within 45 min usually, the longest a melt has gone was 1hr 45min and the furnace looked pretty beat up and sad/fubar. So i rebuilt my furnace shortly after. i have used what "devil-forge" provides but it didnt last very long from memory. I figured out the devil-forge furnaces can melt cast iron pretty easy. so it was just a little more heat to add
the way i have sent my furnace up is isowool 1600c/2900f.  50mm/2 inches, then coated in ridgidizer (purchased from artisan supplies) 2-4 layers of satanite after the ridgidizer has cured then 2 coats of RTZ washcoat really focusing on the high ware areas (i also coat my crucibles in RTZ i will do another post about that) and as the furnace breaksdown i patch areas with air set refractory mortar 1600c/2900f
The furnace i have been using for 4 years has been the devil-forge 4kg furnace, i have since upgraded to the 10kg furnace but i havent had much time to do a large melt. The new 10kg furnace will let me produce ingots around the 2kg/4lb mark instead of the 800g/2lb ish but thats much larger then i can manage so a friend has offered for me to come stay with him for a weekend and use his power hammer so im looking forward to that.

99smithingirl has reacted to this post.

Now that is an option. I am debating between the 4 kg and the 10 kg. I am leaning towards the 10 kg furnace, please do share if you can test to see if you can consistently/easily get to temp in the same time as the 4 kg furnace, as that will be my deciding factor.


Think it might be worth buying this furnace and saving time/money on buying parts individually and fabricating a furnace design on my own.

Edit - I won't be getting a power hammer ever, unfortunately, but may get access to one in the future. I will definitely be working to get a clark forge press (table top 24 ton). Would be hand forging for the most part. I think I can still probably use a smaller crucible for the 10 kg forge so I only make ingots small enough that I can hand forge out without requiring a power hammer/press.


Edit 2 - I read elsewhere that generally speaking you will need a a blower for anything over 10 pounds. This is making me think perhaps the 4 kg option without a blower and if I do get the 10 kg option, I will definitely get a blower, but will require more work. Hope to see what you find with your solely venturi burner setup on the 10 kg.

ABS Apprentice Bladesmith. Documenting my journey bladesmithing and sharing my interest in Indo-Persian antique blades and Wootz steel! ⚒️🗡️

@99smithingirl Ooofff I have hand forged several ingots and that is quite the chore lol! I highly recommend a hydraulic press (or at least a friend you can talk into being a striker lol)!


@ajfmetalworks I think that largest ingot I have done was about 3.6 Kg. It was just so unwieldy to move around. 2.5-3 Kgs seems like a pretty decent sweet spot.

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