Electric Arc Furnace?

I'm trying to make a furnace that can melt metal.  I've done a lot of thinking on it, and I decided that I'm going to make an Electric arc furnace for a multitude of reasons. I plan to use an arc welder as the power supply, with two carbon rods as the electrodes, creating an arc just above the crucible to melt the metal. I was wondering if anyone has done anything like this before?  I plan to have the furnace body made out of firebrick and refractory cement. Would this pose any problems? Also, how much strain does this put on a welder? Will it need to be shut off after a while due to overheating, or can it sustain it's own? Finally, How much power does a typical arc welder use? (in terms of watts) 

Question by tylervitale   |  last reply


Hi, i have an idea for a more eco-friendly blast furnace.

 Its a simple furnace except with a top leading to a chimney (like a fireplace). Halfway up there is a change in the pipes, instead of going straight up, it leads slightly downward til it reaches a pool of water, where the pipe emits the smoke into the water. After wards the smoke will come out from the water and up into another chimney leading straight up to escape. Do you think the water would be able to clean at least some of the air impurities? Here is my picture for a basic idea. Comments and ideas are welcome.  P.S. -I got this idea from a bong (no i'm not a pothead nor have i ever tried).

Question by TALLJ29   |  last reply



How does this furnace work?

I just bought a "custom crucible furnace" from a local university's surplus department and I have absolutely no idea how to get it working. It is roughly 4 feet in diameter and 4 1/2 feet tall, it has 6 'coils' of metal attached in series with thick ribbon-y cable at the top. The side has a 'band' that sticks out but as far as I can tell it is hollow.From what I can tell it might be an arc furnace that something blew up in and damaged a bunch of the components. I really want to get it working as I've been saving aluminum cans for a long time and scrap metal so my plan now is to just hook up the cables to my arc welder and see what happens :) but if anyone knows anything about it or where I can go to get more info that would be much appreciated!

Question by bravoechonovember1   |  last reply


How could I make an igniter for a waste oil furnace/foundry?

I am making a waste oil furnace/foundry and don't want to have to use charcoal to ignite it everytime, so I am thinking of buying a 15000 volt neon sign transformer and using nails or tungsten TIG electrodes to ignite it. Would this work? I can't find any places near me which sell tungsten TIG electrodes? I was worried about using nails because I think they might melt from the tempature of the flame. Is that true?

Question by snowluck2345   |  last reply


Can a 30 gal steel drum barrel stove inside a 55 gal drum heat chamber be integrated into existing HVAC?

I want to make a wood burning stove in my basement using a 30 gal steel drum for the burn chamber. Now the interesting part: The 30 gal drum will be inside a 55 gal drum, which will be the heat chamber. Will I be able to use this setup to partially or fully heat the 2000 sq ft upstairs? I was thinking of using a below grade through the wall stovepipe kit with integrated cold air return hooked to the 30 gal barrel, and then attaching the 55 gal heat chamber into the existing HVAC ducting. I would create the burn chamber with one of the many barrel stove kits like those available from US Stove. Bonus question: if this is possible, can I double the fun with a tandem setup (side-by-side or stacked) connecting the outer 55 gal heat chambers with a duct?

Question by sthain   |  last reply


How can you prevent Galvanic Corrosion? Answered

My parents bought a new green heater they've had repaired by 2 different guys in the past 2 months. The last one was a guy my brother knew; he said that it needed to be sanded, which I thought was a bit strange. It's beginning to act a bit funny again, kicking on, then going off. So I opened it up today, thinking that it was probably Galvanic corrosion from the way he talked. It seems as if a few companies are getting a bit careless in there designs. :-) So I opened it up and there was still corrosion laying on the bottom of the case from the first fix. He didn't even know what I was talking about. I read the Wikipedia article: Galvanic Corrosion. They mostly advise electroplating, which could get a bit labor intensive in this case. From what I understand, the idea is to separate the base metals, the anode and the cathode, from the electrolyte. In this case, it's the water vapor in the air. Wouldn't it just require some type of heat resistant coating to act as a barrier against water? Like some kind of spray on coating?

Question by Vorenus   |  last reply


i need help designing a coal furnace to reach tempuratures over 1300 celcius

Hello, after remembering my trip to sovereighn hill when i was 10, and remembering learning how gold bars were made during the gold rush, seeing that a small wood / coal powerd furnace( 1 Metre high 0.7 metres wide) made from clay , was capable of melting gold (melting point 1060 celcius), and having long discusions with my friend as to what method we were to take , in building a sodium furnace, i sugested we build a furnace and make our sodium metal using the deville process involving boiling sodium carbonate and carbon together then passing the metal and monoxide gas through oil. and we agreed on this as we could smelt metals with it also, make grinding media ect, and it would be cheaper than using propane. now that i have decided to make this furnace, based on what i saw when i was 10, i need help designing it correctly, so that it acheives tempuratures in exess of 1300C, the one at sovereigh hill i was told could reach 1500C. at the moment, my idea is that i can build the furnace 1M high and 50cm wide (roughly ), out of bricks and mortar, then fuel it with coal, eventually after being pre ignited by wood. at the base, i plan on having a small vent which i will pump air into using a small inflatable matress inflator, to supp,y the furnace with air. at the top it will have a small round hole in which i will insert things to smelt, which lie inside a ceramic pot .in the case of making sodium via deville proccess, it would have a steel pipe sealed off at the base, reduced at the top running nto a deep cooled oil bath also at the top, there would be two small vents to allow air flow as there air must go somewhere being pumped in. what i need to know, is if htis will work, and if i need to place my ceramic pot right inside the furnace, or just partially in it, as in the diagram of my design. i am asking all this as i have no idea if it will work at this small size, and because i have little experience or knowledge of the potential tempuratures that can be acheived.

Question by oldmanbeefjerky 


How do I adjust the pilot light on an older Intertherm Furnace?

I have an older Intertherm Furnace with a Unitrol controler Model 110ER and I need to turn up the pilot light on it.  It was working perfect, never going out. Then this summer the my propane company replaced the pressure regulator on the tank and since then I have had a problem with the furnace staying lit. It appears to be getting blown out sometimes when the main burner lights. The gas does not light immediately but instead delays and builds up a little and then when it flashes it blows itself out. So I need to turn the pilot up. I have spent hours doing searches but I have not found any manual or instruction on how to turn up the pilot in this model. Anyone have an idea as to which screw to turn and how much?

Question by Vyger   |  last reply


making a (more) permanent mold from cement/concrete for aluminum castings?

Hey I've been looking into aluminum casting for a while now (done it once or twice with different "furnaces")  Now I'm reading alot about lost foam casting (sounds interessting too) But I was thinking; do you think (/have experience) that I could make some kind of "permanent" mold out of some kind of cement/ concrete/ fireclay mixture for casting similar pieces several times?? I was thinking, when you make the furnace(s) you make a cement/ concrete/ fireclay mixture that can withstand the temperature, so shouldn't it be able to withstand the temperature of the aluminum being poured into it also? (and therefor be able to make the mold out of) - I was thinking to use a special type of cement ment for use around a fireplace. What do you know/ think of the idea? - and also; is there any (other) cheap/ "easy" way to make permanent molds for several similar castings? (at home/ the backyard) PS. not important but I've made/ used a coal fired furnace, a gas (butane) fired furnace and now I'm about to build an electrical furnace (for the sake of expence and time of heating up)... I'm trying to make some casting sand/ green sand, but the ingredients looks to be rather difficult for me to gather (In Denmark Europe)

Question by lordl9999   |  last reply


Building a Foundry?

So I've been experimenting with building a mini foundry made out of steel cans. I've experimented with several different fuels, fuel injection systems, oxygen injection systems, crucibles, and different metals. However, the only metal I've ever been able to melt with it is zinc. (if you don't know, zinc doesn't take alot to melt; only about 700F) My target metals are aluminum and copper, but despite over a year of experimenting, I've never been able to melt either. I would like to know what I'm doing wrong, or what I could do better. Here's the rundown of the furnace's construction: The fuel I'm currently using is propane. The foundry isn't big, (you could fit it in a backpack) so I just use propane canisters for torches with a normal output line on the end. The line runs to a small piece of glass laboratory tubing with a tiny nozzle on the end which is about 1 mm in diameter. The propane shoots out as a stream and mixes with air utilizing the venturi effect. The propane mix then shoots into a large metal pipe about 2 cm in diameter. It then bends up at a 90 degree angle and enters the furnace, which is in essence, a steel can with a hole in the bottom. inside this is a steel can cut in half with a thick wire through it to suspend it above the burner.  So what could be improved? When I run it at full blast, the whole furnace glows orange, but no metal melting happens...

Question by tylervitale   |  last reply


Does anybody have a set of plans for a downdraft sanding table using an old furnace blower?

I have seen numerous 'threads' and discussions on the subject, but no PLANS other than a few pictures.

Question by GrumpyOldGoat   |  last reply


What is a recipe for refractory cement in small amounts?

Https://www.instructables.com/id/Mini-Charcoal-Furnace/#step1 This has me wanting to make my own foundry, however i can't find how to make refractory cement, and nutandbolt doesn't list his own recipe. Alternatively, Where can I buy refractory cement in Australia?

Question by Nagarok   |  last reply


whats d temperature needed to melt soda cans? how good r they for investment casting? Answered

Simple. i want to  melt these cola cans (and beer cans too ! ) so i can use it to cast some stuff. interested mainly in investment casting (lost wax method). need to know the temperature. precautions and possible cases of going wrong. i have an  electronic muffle furnace. if it helps.. regards,  Chakra

Question by chakra   |  last reply


what are some easy ways to melt galena? Answered

I have found some Galena, an alkali metal ore containing silver and other metals, and am trying to melt it down to extract the silver to use in jewelry making. I have tried to melt some with a mapp gas torch with no success, it does not seem to heat enough that I can seperate the metals. Does anyone know of any cheap and easy solutions to extracting the silver without haveing to build a furnace.

Question by jamesrboster   |  last reply


make a solar steam boiler to power a turbine ? Answered

Quite recently my gand father just ditched his satelite tv service for cable and hes got a 15 foot dish. i  have been staring at it trying to figure out what i should do with it and ive decided on solar furnace to power a steam turbine. im two weeks in and im out of ideas for how to produce a sufficient supply of steam and travel it far enough to power a decent turbine. i just need some fresh ideas to run with to get my brain working again any and all thoughts brilliant and stupid are welcome

Question by snowfox222   |  last reply


how do i get manganese metal from manganese dioxide? Answered

Hello, I have a very large amount of manganese dioxide, which i wish to turn into manganese metal, however, i have a problem with reducing it with carbon, which is that i dont have a furnace, or even the materials for a makeshift one, as i found out all the bricks that are sold in this state, are all sand or cement, no clay, not even at the hardware store. I was wondering, if there is any way for me to get manganese metal other than reducing with carbon, such as electrolysis of manganese in some soluble form. thanks

Question by oldmanbeefjerky   |  last reply


Can anyone help me with metal casting?

I have been working with my friend, setting up a small IT business in our local area providing some software but mainly hardware. Now that I have a furnace and it can melt aluminium my friend has asked me to cast a case for his computers. He said that he will produce a wooden copy of what he would like it to look like, then give it to me to cast. I am wondering how I can convert the wooden copy into a wax copy so that I can continue from my own knowledge. Any help would be greatly appreciated. Thomas

Question by thomas9666   |  last reply


Green sand options? Answered

I finally finnished my testing prototype of my metal melting furnace. Did a few casts to get short rods for the lathe work and noticed a big problem. I used washed play sand as itwas the finest sand I could find locally. The result was good in shape but very bad in terms of surface quality. For another test I used the leftovers of my crushed perlite and mixed it bentonite and the surface was really smooth - but using perlite is not really an option. Real green sand is hard to get in my area and the postage costs for a 20kg bag are just too high on top of it. So, before I start hunting down all sand and soils shops nearby: Is there a proper name for extreme fine sand or a good alternative for a reusable casting media?

Question by Downunder35m   |  last reply


What is the Best Way for a Do-It-Yourselfer to make a few good Diamonds? Can I just Heat some Methane and add Water? Answered

I'm looking for practical ideas and expertise with making such things. I have a Wood Furnace that gets hotter than 1000 F and a tiny Camp Stove burning Pellets.  I have Propane for the Carbon. Water could be used to a little Hydrogen or Oxygen. I would like to make a 1 carat Round Brilliant Cut perfect Diamond and a 1 1/2 inch Maltese Cross looking Diamond as perfect as possible. I believe I could make the 1 carat Diamond in a 1/2 inch tube using a low quality Diamond as the substrate and target at the end of it. I would have to activate the gas mix moving through the tube just before the substrate. Do I need a Microwave or UltraViolet Light or something? I need some Know-How and Inspiration.

Question by Zues.gods   |  last reply


What is the hardest titanium alloy i can smelt myself? Answered

Hi, Recently ive been looking into titanium alloying, i have access to a large amount of chemically pure titanium scrap, and want to alloy it into the hardest possible alloy i can, so i can build some very tiny yet strong mechanical objects as well as a titanium knife. the means by which i wish to produce the alloy is with an induction furnace My problem is, ive google searched, but cant find what the hardest suitable titanium alloy is, previously i thought titanium steel was hardest, but then i learnt that titanium aluminium is the best. Everywhere indirect terms are used like "best" and "most " and often they only talk about pure titanium vs steel alloys. Im really confused. I just want to know what the hardest titanium alloy is. What is the best titanium alloy i should make for use as a blade and for high strength structuring, e.g frame body for small robot i want to make as indestructable as possible. thanks

Question by oldmanbeefjerky   |  last reply


Global warming & carbon emmissions

I may be off on a tangent to reality, but I wonder if there are any statistics available on the effect of all the Tonnage Oxygen plants around the world sucking in all the oxygen, separating the various gases & storing them in pressurised liquid form. I did a quick search today and 2 countries alone were 'manufacturing' (sucking in our air, separating the elements and producing) 26,000 tonnes of approximately 99% pure oxygen per day! To the crux of my question: Is this action (carried out on a worldwide scale and potentially growing) upsetting the balance of our atmosphere - we are all informed by the press and by the scientists that global warming is (or may be) attributed to mankind burning fossil fuels and dumping the excess carbons into the atmosphere. I just view this as the flip side of the argument........ has anyone ever considered the tonnage of oxygen drawn in from the atmosphere by these plants which is sold-on essentially as bottled gas or piped to be used for oxidising other materials (blast furnaces, basic oxygen steel-making, scrap cutting  etc), could be having an equal or bigger impact on our atmosphere and global warming than the straight burning of fossil fuels by power stations and automobiles etc? Just 'throwing the idea out there' (Liquid oxygen when spilt and viewed as a puddle, appears blue like the sky, the deeper the oxygen puddle, the more vivid the blue became ..... reminded me of when I was a kid the sky looked a lot bluer than it does these days).

Topic by Ttrick   |  last reply


What am I doing wrong with Lost PLA investment casting (aluminum)?

I've tried several times to get lost PLA investment casting to work, but it never turns out great.  In the photos you see an attempt at casting some 3D printed pulleys.  Interestingly enough, the one furthest from the sprue turned out the best, but there are still pieces missing and the details aren't as good as they could be. I used 6061 scraps for the melt.  I've tried adding a bit of boraxo/boraxo+salt.  I've tried without it. The mold was made by using 325 mesh silica and plaster of paris about 45 to 55% respectively.  This produced far better details than with play sand, but still not great. After casting the mold I let it sit for 12 hours or so, and then baked it for 2 hours at 350 F, and then 2 hours at 500 F (upside-down), and then put it in the propane BBQ grill for 2 or 3 hours at max heat.  I then blew out the ash using a can compressed air.  In this photo I even kept the mold heated until just before pouring, and then I put it into the furnace until the top level of aluminum re-melted. You can see that I have several vents (2 for each pulley) and a very large sprue.  The sprue fills quickly before anything comes out of the vents. Once the aluminum melts I set a timer for 3 minutes and allow it to continue to heat before pouring. Any advice is welcome from those with experience.  Also any photos or videos of how you've made it work would be great! The pulley's I've printed are from http://www.thingiverse.com/thing:343343.

Question by als_liahona   |  last reply


i want to extract the tin from some tinned copper wire. how do i go about doing this?

hello, i would like to know, what the best way would be to separate tin from tinned copper wire. i recently attempted to build a MOT welder and now am left with quite alot of wire, and i require the tin for tin oxide. im wondering, what would i need to do, after i dissolve all the wire in hydrochloric acid, to extract the tin? its my understanding that tin and copper chlorides decompose easily into their oxides, and i only need somewhat pure tin,  as the electrode connector for my MMO titanium mesh (the part which will stick out of the cell which i will connect the cables to), and i only need roughly 70-80% pure tin metal, which i will reduce using my furnace and some pure carbon, in order to get a metal. or would it be ok for me to just melt the metals as is and let them separate in the crucible, and have all the fiberglass and resin just burn off? otherwise, would heating their chlorides (i require a soluble form to filter away resin and fiberglass), yeild tin oxide and not copper oxide, or would weaker acids like carbonic acid be able to dissolve the tin? sorry for all the questions but i really need some tin and i dont wanna blow this one shot i got here! i already have a theory on how this will all work, i just require a second (somewhat) proffesional) opinion. also i am already taking full precautions to ensure i dont get chlorine poisoning, so dont bother with the warnings. thanks.

Question by oldmanbeefjerky   |  last reply


Distribution of Solar Heated Water and Any Other Heated or Cooled Water

I started this project about a week ago after seeing the Instructable – https://www.instructables.com/id/How-to-build-a-strikeheliostatstrike-paraboliI made mine out of cardboard and then coated the cardboard – front and back – with fiberglass resin for stiffness. I covered the inside with tinfoil to test it out and find the focal point. It worked great with the focal point at the center of the dish even with the lip of the curve. I then removed the tinfoil and replaced the tinfoil with mirrored Plexiglas. Now it works awesome. I have a 30� parabolic mirror that can ignite wood almost instantaneously at the focal point of the light.Next I constructed the heating coil to run water through. This is made from a large 1 Kg coffee can, 16’ of ¼� copper tubing with end fittings, and the glass lid of a small sauce pan (handle removed). The outside of the coffee can is painted flat black as is the copper pipe. The copper pipe is coiled to a coil 4� in diameter and 6� in length and inserted inside the can with the ends extending from the side of the can through two drilled holes. The inside of the can is not painted, but left shiny. The glass lid is then taped over the hole with aluminum metal tape covering a minimum amount of the glass – about 1/4� around the edge.The coffee can is then suspended over the mouth of the parabolic mirror by a three point 6� chimney pipe stand-off. The can’s mouth is centered at the focal point of the mirror so all of the light being reflected by the mirror must enter the coffee can. Hoses are hooked up to the copper pipe fittings and these lines go to the feed/storage tank.The problem with the conventional set up from here is that the speed the water moves at (slow) to be heated to a great degree causes such great loses through convection, this system is not really feasible. I propose a new idea – or a new twist on an old idea.I noticed that the solar heat generating station use a black water pipe inside a glass vacuum tube to generate heat from the sun for heating water. I said to myself that this is a great idea and plan on building the next heating coil in a vacuum chamber. But, I also came up with the idea that the if the water is heated in this manner, why can’t it be transferred to the storage tank in a similar manner.If the feed lines were suspended inside a larger outer line and the outer line sealed tight and vacuumed the heat transfer due to convection would be almost nil. I estimated that with a total convective area at 100% the use of plastic stand-offs (8 @1/8� thick over 12’) the convective area would be reduced to 0.6%. Unbelievable! Even if this rose to 5% it is far beyond anything in use today by the home owner. Stretches of pipe going 100s of meters would no longer be un-heard of. You could place the dish in a close by field away from the trees and house and pump the heat back without losing it to the ground.This would also work for outdoor wood furnaces if use today. An outer pipe could be added over the existing pipe work, sealed, and vacuumed – almost all heat lose would be gone. And much larger stretches of pipe could be used here also. They would no longer need one furnace for the barn and another for the house. With this system, the pipes could even be run above ground, if desired, in some cases.This could also be used to replace insulation on cooling lines also.The key to the system is minimal contact between the inside and outside lines, and the vacuum between the two lines. Remember, there is no transfer of heat through convention within a vacuum, because there is no air for the heat to transfer through.As with all the new ideas this could get costly depending on the scale of piping you are dealing with – but the savings from reduced heat lose will far out way these cost in the near future.I may get an Instructable out for the Energy efficiency contest, but will be hard pressed.

Topic by strmrnnr   |  last reply