Hi, I don't post here a lot but I'd like to get some ideas for the following project.
I'm thinking about building a furnace for melting aluminum. I've watched a lot of YouTube videos for ideas on how to build the actual furnace, and there are certainly many different ways of doing that. I'll be using wood as a fuel source which is a lesser used fuel, but there are actually quite a few wood-fired furnace examples on YouTube. The problem is that I'm not really thrilled with any of them as they seem to fairly random in the way they are used. Some people have furnace that just barely melt the aluminum other have actually produce wood heat that far exceeds the temperatures needed. And that's actually not good for the Aluminum.
In fact, this is the reason that I would like to monitor the temperature. I'd like to be able to control the blower so I get just the right temperature to cast the aluminum without over-heating it unnecessarily. So I thought I'd post the project here as a question to get ideas.
I have come up with some ideas already on my own. In fact, the best idea I've come up with thus far is to employ the use of a small steel bar maybe 1/2" in diameter that transverses the furnace wall, Then attach a high-heat-tolerant resistor to the end outside the furnace. Then just monitor the temperature of this steel rod and "extrapolate" from there to calculate how hot the hotter end must be. I could probably calibrate this over time to work, assuming the idea works at all.
Another idea I had, but I'm not sure how to implement it, is to have a sensor that "looks" through a hole in the furnace at the internal flames and reports the frequency of light received, and then calculate the temperature from the flame wavelength. Like I say, at this point it's just an idea and I'm not sure how I would actually implement it.
One thing I would like to add is that it's imperative that this is an extremely low-cost project. I have plenty of Arduino boards, and I'm willing to program one for this project. But I can't be paying out several hundred dollars for a commercial temperature reader. So this needs to be a DIY electronic project that can be done for peanuts.
It doesn't even need to be electronic if anyone has any other suggestions. But I'm thinking a nice electronic readout would be cool. In fact, if I'm using an Arduino to measure the termp, I could then also program the Arduino to control the furnace blower and that would even be better yet. That way it would be a totally automated furnace that monitors and keeps precisely the right temperature all on its own.
I can figure out the part of getting the Arduino to control the blower, what I need is a dependable temperature sensor.
Anyway, I'm just looking for ideas, so all input is welcome. Thanks.
By the way I haven't built the actual furnace yet, so when I do build it I can include whatever hardware is required for this sensor to work properly.
~~~~~
I just had another idea as I was typing this. What if I put a steel bar trough the furnace so it sticks out both sides. Then attach wires to that rod and run a small current through it. Does the resistance of steel change with temperature? Maybe I could just use the steel rod as the actual "thermistor"? I actually like that idea if it would work.
I'm thinking about building a furnace for melting aluminum. I've watched a lot of YouTube videos for ideas on how to build the actual furnace, and there are certainly many different ways of doing that. I'll be using wood as a fuel source which is a lesser used fuel, but there are actually quite a few wood-fired furnace examples on YouTube. The problem is that I'm not really thrilled with any of them as they seem to fairly random in the way they are used. Some people have furnace that just barely melt the aluminum other have actually produce wood heat that far exceeds the temperatures needed. And that's actually not good for the Aluminum.
In fact, this is the reason that I would like to monitor the temperature. I'd like to be able to control the blower so I get just the right temperature to cast the aluminum without over-heating it unnecessarily. So I thought I'd post the project here as a question to get ideas.
I have come up with some ideas already on my own. In fact, the best idea I've come up with thus far is to employ the use of a small steel bar maybe 1/2" in diameter that transverses the furnace wall, Then attach a high-heat-tolerant resistor to the end outside the furnace. Then just monitor the temperature of this steel rod and "extrapolate" from there to calculate how hot the hotter end must be. I could probably calibrate this over time to work, assuming the idea works at all.
Another idea I had, but I'm not sure how to implement it, is to have a sensor that "looks" through a hole in the furnace at the internal flames and reports the frequency of light received, and then calculate the temperature from the flame wavelength. Like I say, at this point it's just an idea and I'm not sure how I would actually implement it.
One thing I would like to add is that it's imperative that this is an extremely low-cost project. I have plenty of Arduino boards, and I'm willing to program one for this project. But I can't be paying out several hundred dollars for a commercial temperature reader. So this needs to be a DIY electronic project that can be done for peanuts.
It doesn't even need to be electronic if anyone has any other suggestions. But I'm thinking a nice electronic readout would be cool. In fact, if I'm using an Arduino to measure the termp, I could then also program the Arduino to control the furnace blower and that would even be better yet. That way it would be a totally automated furnace that monitors and keeps precisely the right temperature all on its own.
I can figure out the part of getting the Arduino to control the blower, what I need is a dependable temperature sensor.
Anyway, I'm just looking for ideas, so all input is welcome. Thanks.
By the way I haven't built the actual furnace yet, so when I do build it I can include whatever hardware is required for this sensor to work properly.
~~~~~
I just had another idea as I was typing this. What if I put a steel bar trough the furnace so it sticks out both sides. Then attach wires to that rod and run a small current through it. Does the resistance of steel change with temperature? Maybe I could just use the steel rod as the actual "thermistor"? I actually like that idea if it would work.
