Ceramic parts

Discussion in 'General Electronics Chat' started by kubeek, Aug 26, 2013.

  1. kubeek

    Thread Starter AAC Fanatic!

    Sep 20, 2005
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    Hi, I need to make a heater element, and the final candidate for the base material is some form of ceramics or porcelain.
    Does anyone have any experience with making such thing? The main question for me is what kind of clay or mixture I should use. I need it to be tough like for example ceramic fuses etc, and need it to be non-toxic.
     
  2. Metalmann

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    Dec 8, 2012
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    You'd be better off buying the ceramic/porcelain insulators.
     
  3. kubeek

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    Sep 20, 2005
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    I know I would, but I didn´t find any suitable shape anywhere. And since I like to experiment I don´t mind trying this on my own.
     
  4. GopherT

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    Nov 23, 2012
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    What are you trying to heat?

    What temperature?
    What shape and size?
    How many watts will you need?

    What voltage do you have available to power the heater.
     
  5. kubeek

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    Sep 20, 2005
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    Heating comes as the second part, I will probably use nichrome wire.
    The main goal is to heat the ceramic core (right now I imagine a cylinder 35mm wide and about 35mm long) to some temperautre between 150°C and 300°C and basically use it as a source of heat to heat air passing around and through the core. It could be similar to this https://www.google.cz/search?q=ceramic+heater+core&num=100&safe=off&client=firefox-a&hs=32N&rls=org.mozilla:cs:eek:fficial&source=lnms&tbm=isch&sa=X&ei=PqMbUqD7NsnGswaT0oDQBA&ved=0CAkQ_AUoAQ&biw=1920&bih=978#facrc=_&imgdii=_&imgrc=srw4yaMJgI6o8M%3A%3BdsnEO9aEUEg1PM%3Bhttp%253A%252F%252Fi00.i.aliimg.com%252Fimg%252Fpb%252F268%252F742%252F364%252F364742268_347.JPG%3Bhttp%253A%252F%252Fwww.alibaba.com%252Fproduct-gs%252F441164449%252FLeister_ceramic_heater_core.html%3B615%3B461 but I want a higher surface area and want it to be better suited to attach the heating wire.

    It will be inside an insulated chamber, so the power requirement won´t be too high, maybe 50-100W. Voltage will be something safe, most likely an atx psu.
     
  6. GopherT

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    Nov 23, 2012
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    You can use two mica insulators for TO-3 transistors. Cut each half-way though and slide the two cuts into each other to have a 3D structure that makes a "+" when you look down the axis. The mica insulators can be easily cut and are widely available on eBay or other sources.

    Alternatively, you could use a ceramic or glass bead from a craft store - your wife/girlfriend may be able to point you in the right direction.

    Another option is to use metal - e.g. aluminum extrusion. I know it conducts but the temperatures you are asking for are perfect for KAPTON tape. Simply wrap the metal (Brass, aluminum or even steel) with Kapton tape before you apply your nichrome wire. The Kapton is very heat resistant, thin and can even be used to keep your layers of nichrome separated.

    Finally, some 'vitreous enamel' wire-wound resistors in the range of 3 to 6 ohms work well to get the temperture you need at 12 volts. Put several in parallel electrically but in series in your flow path to get the power that you need. Each can handle 25-90 watts (I know from experience they can handle much more if you have air cooling).

    [​IMG]

    Or lightbulbs (two or three in series). The type used for automotive turn signals or brake lights (about 25 watts each).
     
  7. mcgyvr

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    Oct 15, 2009
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    alumina silicate ceramics. can be machined (w/carbide tooling) and available in all sorts of rod dimensions. suitable up to 1000deg C
    (or other higher priced but easier to machine ceramics)

    or you can cast your own shapes but need a furnace to fire them in (and a mold cavity)..
    or get them cast..how many do you need?
     
  8. kubeek

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    It will most likely be a one off.
     
  9. djsfantasi

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    Apr 11, 2010
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    Check out ceramic supply houses or cerzmic classes near you. They may be able to put you in touch with an artist of hobbyist who could make it.
     
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