# Another totally useless idea from rusty



## rusty (May 5, 2013)

Recently acquired a commercial Hobart dishwasher, the heating element in the picture was custom formed by wrapping it around a 2 inch diameter pipe.

The purpose of the wrap was to see if the element would still work, which it does. Now I know that I can custom shape these and other types of elements into any shape I desire.

I like the idea that the dish washer elements have a water proof fitting on each end, I'm thinking that I can warp the element small enough to fit inside a pipe then using a rheostat from a hot water tank control the temperature.

From the same discarded dish washer got two nice temperature gauges scaled in Celsius and Fahrenheit.

You can find these types of elements inside oven ranges, they'll work on 110 volt but you will get better performance off of 220 volts.

If your not comfortable playing with electrical currents leave this project alone.


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## srlaulis (May 5, 2013)

Useless??? No. Using your brain to create something useful out of ingenuity....admirable.


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## resabed01 (May 5, 2013)

You need some grounding :shock: .... don't fry yourself!


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## Geo (May 5, 2013)

could be useful building a heating tank for AP.


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## rusty (May 5, 2013)

srlaulis said:


> Useless??? No. Using your brain to create something useful out of ingenuity....admirable.




Yea I posted this idea and perhaps should have elaborated more on it.

For instance an old oven element could be shaped as such to slip over a crucible for melting silver, one could even embed the element in refractory in which to insert your crucible or wrap it in cerwool also known as kaewool.

Discarded ranges and dishwashers by the score all for free.


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## rusty (May 5, 2013)

The first picture the element is hooked up to 110 volts, in this youtube video the custom shaped element is hooked to 220 volts and it heats instantly.

[youtube]http://www.youtube.com/watch?v=bzAmdSlJnZo&feature=youtu.be[/youtube]


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## rusty (May 5, 2013)

Geo said:


> could be useful building a heating tank for AP.



Yes by using a thermostat from an old electric hot water tank you would be able to control the temperature.

These thermostat such as the one pictured below are designed for physical contact to the outer shell of the tank. These are no circuit breakers so be sure to use the appropriates sized one for your project.

The same thermostat could be used to bring a small circulation pump on-line, the Grundfos pumps are fractional horse power drawing much less amperage than a 1500 watt heating element. Your line feed could be either 110 or 220 volts.

These thermostat and those from electric ranges are a great source of scrap silver they have large contacts inside, the case is made from Bakelite you can easily break them with a hammer.

In fact I recommend using a GF breaker.


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## butcher (May 5, 2013)

rusty, that is actually a thermostat switch, not an actual rheostat, that is why they are mounted to the tank to operate from the tank temperature.


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## rusty (May 5, 2013)

butcher said:


> rusty, that is actually a thermostat switch, not an actual rheostat, that is why they are mounted to the tank to operate from the tank temperature.



Good catch, wish more people would correct me when I'm wrong.


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## skippy (May 6, 2013)

I have shaped sheathed elements from stoves to make custom heating apparatus and they form ok as long as you don't try to bend it too tightly as the sheath can break. I cover the connections with some fep tubing to insulate against accidental shock. I used it to keep heat a water bath for SSN leaching. I also used them to make a roasting apparatus for roasting catalyst with sulfuric acid. Another really useful product is Roxul Drainboard. It's used to channel water to the bottom of foundations, but it is pretty heat resistant and dense enough to support weight. The water bath was a keg sitting on the roxul board with the element tucked under the keg.

On 120v they get half the rated power, which can be handy - as they can be connected to a common light dimmer (check the dimmer rating). If you try to imbed the element in refractory it will likely melt the nichrome/kanthal wire that is inside the sheath though. Bad idea imho. The elements need to be able to disapate heat in some semblance to their application. A water heater element needs to be in water to keep from melting out. A stove element is made to get red hot, so you can use it at that temperature or a little more. I've used a stove element to make a temporary furnace for heat treating carbon steel, and it worked well, although the long term durability is not known. I'd guess melting silver or copper would either be really pushing it or even not possible. Aluminum yes, brass maybe.


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