My IFB/fibre-blanket furnace build.

As promised

 

Thanks David. First I need to get a cup (or the last thing I need to do is get the cup).

One thing I did notice, when the mixture was a little too rich, I lost the roar sound coming from the furnace. I didn’t really push its first light too hard. I had it burning for about 30 minutes. I burnt 3L(0.8 gallon) of diesel, and 1.5L(0.4 gallon) of WVO. I guess I’m about 9 L (2.4 gal) per hour.

I shut it down at 3:30 PM. . 7 hrs. later, I just checked the temperature, the inside brick is still 270°C ( 518°F). (Edit; 20 hours later has a temperature of 65°C)
Wow, I need to figure how and where I’m going to store this. And I have no clue what my running temperature was.

I got this pretty cool picture about 10 minutes after it was shut down.

 

One thing about running a furnace is that the furnace combustion behaviour will be completely different with and without a crucible.

 

Mark, I’m with you on this... but, our fearless leader really wanted to just see a burn(nothing more or less, now Iron). First flame, now he wants to a iron melt! Gee, i guess, I got my work cut out for me!

I can see how dozen things or more can change depending on crucible size . I am thinking probably my maximum crucible size will be in A20 (with a go to A16) . I think I might be able to tweek to anything smaller.

 

A clay flowerpot might make a good single use crucible substitute so long as it's fairly dry and not full of trapped moisture, maybe bake in an oven beforehand to avoid steam induced damage. You could even put some sand/clay in it and a few sample aluminium, brass and iron test samples and see which melts. For iron you'll need to get well into yellow heat from what I have experienced, as orange glowing refractory/crucible temps will just get iron soft, a crucible in there may aid the combustion and flame path.

I plan to try some monel (1300-1350 deg C) and 316 stainless (1500-1540 deg C) at some point to see if they melt.

 

Aluminum, copper, brass, bronze then cast Iron???

 

I was able to melt aluminium and brass with incomplete combustion, in that the fuel was still combusting as it left the furnace. It would only soften iron not actually melt it so iron is a good test of a furnace.

 

Lol. I am a little bit special the way I learn. I always start in the shallow end.

Yeah, it’s taking me five weeks to build this furnace(Some guys here build in a weekend). It took me almost 3 hours of testing the oil flow rate to have a maximum of 200 mL per minute but, 175 mL/m was my goal . My fuel lines only have a 3/16 ID and just shy of 15 feet. And I have not cut (or diluted) the oil. My blower did not have enough pressure to deliver the oil uncut. I had to resort to pressurizing the fuel tanks with compressed air. I got my 175 mL/m at 40 PSI., So I just jumped it up to 60 PSI and this gave me 250 mL/m. That little pipe bomb air compressor I’ve had up to 300 psi. Currently it shut off at 175 PSI and on again at 155 psi. It’s just a Freon compressor out of an old fridge. It ran for about 15 seconds with two minutes downtime. My video on the build.


I like to have action plans and action plans for action plans.

My original plan on the lighting fell through. My second plan of action fired it up safely and beautiful. No paper, no wood and about 2 feet away 30 seconds after the first trail light.

I am currently maxed out on my combustion/Atomizing fuel airflow. I had the ball valve full open. To get more I will need to swap out the 1/2” airline for 5/8” or 3/4”. So, I think I’ll take baby steps towards my cast-iron melt.

I don’t jump in the deep end anymore. Now I dive sometimes involving a couple twists and flips 25 feet high.

 

A12 has been ordered. So maybe I will give cast iron a try in two weeks. It sure doesn’t give me very much time to play in shallow end.

 

Maybe I don’t have all the right gear, do you have some suggestions? I have all the welding gear. Jackets, helmets, leather boots and leather boot covers, full to ground apron. I also have three different welding helmets with variable tint and three different tint safety glasses for UV. I also have high thermal foundry gloves, that go to the elbow.

While, I waded in the shallow end,... I will continue with my stainless steel crucible.

New SS crucible and glove.

This time I’m going to weld instead of forge a pourspout. Variety is the spice of life.








No, I don’t have a tinfoil suit.

 

Looks like you have it all sorted out, I'm using leather boots, leather welding spats, cotton trousers, cotton long sleeved shirt, leather apron extended to the top of my boots and leather welding gloves. I'd like to get some leather welding trousers too. I mentioned in another thread that I had a plastic grinding face shield get hit by a small 10mm bit of molten bronze spat out while pouring into a steel mould that wasn't preheated. It hit the mask in line with my eyeball and immediately disappeared with a loud pop: it seems the dirt/moisture on the plastic vapourized and blew the bronze back off leaving a small spot completely undamaged and free of all the dust on the mask surface. I don't recommend using a plastic grinding mask but it did work in my case and was undamaged, I don't think it'll shrug off a bigger splash.

 

OIF's SS crucible lasted him quite awhile. There's a thread on here somewhere about it.
It sounds like you've got the PPE to start. You'll get the feel for what you're lacking if you do a couple of dry-runs. I wear boots with no laces so they'll kick off easily. Molten metal will burn through just about anything and will stick to some fire retardant materials so all of my stuff is pretty easy to take off. I don't put any of the heavy PPE on until I've got metal starting to melt, including my loose boots. Just safety glasses, cap, and leather work gloves. The closer I get to pouring time the more stuff I put on. I pour over sandstone patio block with loose clean sand thinly scattered about. I've over-poured my mold more than once and had runouts as well and the sand does several things, in my mind anyway: it lets any moisture in the sandstone vaporize without being trapped by the metal preventing a "pop", it dampens the impact of a dollop of metal so it doesn't splash so much, and using clean sand allows me to recover the metal without having stones or gravel in it.
I haven't had any mishaps yet, thankfully.

Pete

 

Looks like you can get a gap between your lid and furnace shell on the hinge side. When closing it, it looked like the hinge side hit first and it wasn't clear whether it would set down flat. Everything moves when it gets hot. Is there slop to let it fit down tight with differential expansion? Another concern is the leg. It must be free to rotate after corrosion sets in to avoid two hands required to get the lid supported. Does the foot of the leg get You might consider a paddle to lay over the open lid if the radiant energy is great enough that you have trouble grabbing the crucible in all the heat.

Looked like your first burn was rich, and you mentioned you ran out of air. Good air control is as important as good fuel control to me.

Have you tried opening your lid hot? I agree with the others that it looks like it will be hot to handle, and the hot face up will give you lots more radiant heat to deal with.

My cheap furnace is brick/wool/55 gallon drum. Drum is not discolored after 420 heats. I think your wool will block gas paths without mortar and allow the brick to expand. It will be interesting to see how your lid holds up. I need a big hole in my lid because I load and skim through the lid.

You will probably get a lot better burn than I do with a drip burner and motor oil, but I have to switch back to propane to burn off the excess oil or I get black smoke when shutting down. Do you plan to pull your burners at shutdown?

My setup is low tech. I just dump anything flammable into my fuel tank and then burn away. Stale gasoline does not burn as hot as WVO which does not burn as hot as kerosene which is not as hot as WMO, in my setup. I'm pretty much sticking to motor oil as it is free and easy. It will be interesting to see how much you use your fuel switching manifold.

The aluminized gloves are well worth the money, but they are only for radiant energy. You should have tools where you never need to handle hot surfaces but still need protection from radiant energy.

I used 316 SS crucibles for many heats. They last very well but are subject to melting if you try to get too much superheat on your melt. The wall of my last one failed in midair and dumped the load. I was lucky and need to post about that but have not had the time with my wife passing. I will get to it. After that failure I am less enthusiastic about steel crucibles. I was melting some scrap aluminum from the glass flask videos and thought I could heat enough to make the glass float. All the glass contaminated scrap got discarded after the accident and I am using only clay graphite crucibles.

Your build has been interesting and I am very much enjoying watching so keep it up. Your fabrication skills are great.

Do melt aluminum first until you get your sea legs.