First off, I wanna say I'm thrilled to have found this site.
Secondly, I am a drummer and carpenter in the beginning stages of starting a custom drum company. What brings me here is the desire to make my own Lugs. I have a few really good designs plotted out, and now I need to learn how to take them from the drawing board to reality. So I'm doing some research on casting, machining and polishing metals.
I am on a pretty tight budget and can't afford to build and fuel a gas or propane or forced air furnace. But I can afford to make one of these:
I found that brass melts about 500 degrees above aluminum. I am wondering if an electric flower pot furnace like the one in this video can melt brass. And is it possible to modify one by boosting power or using a larger heating element to reach the necessary temperature? Or will I have no choice but to get into the bigger-deal furnaces?
Truly, this electric furnace is the only way I can go at the moment, as I don't have a suitable place for the dangerous components of other furnaces. So if it can't reach that temperature I have to go with Aluminum, but I really want a brass look on this drum if possible. I have been advised against brass plating Aluminum as it is "problematic". Is this true? It's the only reason I am using brass and need to reach that high of a temperature. And is there any way to make or polish Aluminum to be permanently yellow like brass? That would solve all my troubles.
Any help would be appreciated, and thanks in advance!
I don't know if it will get hot enough for brass. Is that your furnace or something your thinking about building? Good insulation would help keep the heat in. You would just have to experiment.
No, it's not mine. I am planning on building one based on the design. I found a couple videos detailing it's construction, but nothing detailing the temperature capacity or what metals, other than aluminum, it will melt.
I thought about using two, or even three, coils in a larger pot or a bucket to reach the necessary temperature.
Are there any members of this forum that use, or have used an electric furnace like this?
Ok, I have seen two different furnaces; one with a 600W coil, and one with 1000W coil. Now, I don't know what denotes power (or in our case heat). Is it wattage, amperage or voltage?
I read that if the 1000W coil exceeds a temperature of 800 F, it will "fry". The same article mentioned putting a power regulator in place to keep it below that temperature. This leads me to believe that using a more powerful coil will produce higher temperatures in the furnace.
From what I'm seeing in the video, an electric furnace using a 1000W coil can produce temps up to 2000 F - otherwise it wouldn't melt aluminum to the pouring temp. So I am assuming that the overall temperature is a result of the furnace containing and building up the heat made by the coil. Meaning a 1000W coil that will produce temps of 800 F will bring the furnace up to 2000 F. Meaning, if higher wattage denotes higher temperatures, using a 2000W coil will bring the same furnace up to 3000 F. Do I understand this correctly?
I am preparing for a crushing verdict that these electric furnaces won't reach the temperature to melt and pour brass, just in case.
So, I am wondering if anyone here knows a method of durable plating or finishing aluminum to look like brass. Anyone?
I have gathered the stuff to make an electric frunace. I just haven't had the time to put it together. I'm using insulated fire brick with grooves cut into them for the elements. The elements are for a ceramic kiln, I think it's a total of 3000 watts at 220 volt. I just plan on melting Aluminum in it. And heating the basement at the same time. I will also use it for wax burnout, but that will have to be done outside.
As far as changing the color of the Aluminum, I don't think I can be much help. There are metallic powder coatings that look pretty good, and there is a Gun bluing made for Aluminum that will make it a metallic black color. I've looked at gun shops and haven't found any of it yet, I wanted to try it out.
Thanks for the input. So far I've gathered a 2100W heating element for a common household range and 1 gallon of refractory cement. My calculations suggest I will need another gallon of refractory, but that will have to wait until next week, along with the 12" terra cotta flowerpot. I'll buy a couple fire bricks to use as a lid for the furnace.
I know this may not be the best forum to ask about electrical stuff, but one thing that worries me is wiring in the power chord. Of all the information I've found regarding these electric furnaces, there's nothing detailing how to go about wiring the two ends of the heating element into a plug-in type of chord. I'm worried that some kind of power conditioner needs to be wired in between the ends of the heating element and the hot and cold wires of the power chord. Or can I just connect each end of the heating element directly to the hot and cold wires of the power chord and plug it right in?
My main concern is the heating element, and reaching the necessary temperatures. I am hoping that I can reach the necessary temperature to pour aluminum using household 140V, as I do not have access to 220V. Think it's possible?
As far as the brass look, I am just going to have to wait and see. Hopefully this furnace will bring brass to the pouring point. But if not, I will just have to compromise my designs until I can build a furnace that can reach the necessary temperatures. So I think I'm going to save that for the future. Going with polished aluminum is fine for my current project.
Oh, and another thing I could use some advice on is the molds. I am planning on casting pieces 1.5"x1.5"x1". And I need a mold method that can be reused to make hundreds of them. I initially figured to use a sand mold (using just the drag, big enough to make 10 pieces at a time) and pressing my shapes into the surface of the sand. But I will still have to re-build the drag and constantly re-mix and prepare the sand for it after each set of 10 castings. So, to avoid all of that, I want to make a more efficient mold that can be used over and over. I notice that most ingots are poured into metal molds. Well, the parts I want to cast are pretty much ingots, and I am going to have to grind them smooth and polish them anyway, so why not use a metal mold and cast 1.4375"x1.4375"x1.0625" ingots, leaving 1/16" excess for grinding down to size.
Any advice on what kind of metal to use, or answers to any questions that I wouldn't know to ask, would be greatly appreciated.
Who sez that sand won't work for this? What you need is a matchplate and several flasks to go with it. What is a matchplate, you ask? Basically it is a board with the pattern, runners, and ingates already attached to it. Place it between your flask halves, ram up both sides, separate the mold, and voila, one sand mold. Repeat as neccessary. Easy peasy, and WAY cheaper than a permanent mold. Regular old water-bonded greensand is actually pretty forgiving to take care of, and cheap as well. Here's an example:
This is a matchplate I made, and so is this:
This should give you the general idea. Anything you can do to eliminate processing after casting is good, and with a little tweaking of your pattern, you should be able to have the parts come out almost perfectly sized.
