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Dome Installation Video - Casa / Premio / Modena

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For many of you who bought a modular oven, you may have asked how we put the domes together when we build them. For those of you considering one of our ovens, we shot a video to make your install easier.

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https://www.youtube.com/watch?v=-7q7...jSniYogfUra06Q

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vermiculite finishing problem

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  • vermiculite finishing problem

    Greetings,

    I found your website some time ago and appreciate the discussions on vermiculite though we are not in the pizza oven business.

    We are using vermiculite, portland cement mix for ornamental objects including planter boxes. We love the lightweight nature of this product but we are struggling with one major issue.

    The 3 sides against the melamine board look great - it's the open side that comes out dry and crumbly, like there wasn't enough cement in the mix.

    Do any of you have thoughts on what can be done about this? I'm including a couple of pictures for reference.

    We are mixing 2 coarse grade vermiculite: 2 fine grade vermiculite: 1 portland cement.

    Any thoughts appreciated!
    Attached Files

  • #2
    Re: vermiculite finishing problem

    Stop about 3/8" to 1/2" from filling your form. Finish the pour with only fine vermiculite in your (if my math is right) 4 to 1 Mix. The fine will finish as smooth as cement.
    I don't care what folks say behind my back........They are either braggin' or.......lyin'


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    • #3
      Re: vermiculite finishing problem

      If you want to use it to make things like planter boxes then you probably need more strength. You can do this by adding sand and a higher proportion of cement. Lots of people end up using too much water in the mix. This tends to wash all the cement to the bottom leaving crumbly vermiculite on top. I've found about 3 -4 parts water for every part vermiculite works well (the finer the vermiculite the more water you need)

      PHYSICAL PROPERTIES
      MIX PROPORTIONS BY VOLUME

      DENSITY
      PCF COMPRESSIVE
      STRENGTH
      28 DAYS PSI

      cement verm sand wet density dry density comp. strength 28 days
      1 8 0 40-48 19-22 70-125
      1 7 0 42-47 20-24 125-140
      1 6 0 44-52 23-27 135-175
      1 5 0 49-55 25-31 175-125
      1 4 0 55-62 30-35 225-325
      1 3 2 85-91 75-80 600-620


      Sorry about the table but it doesn't like the format, but as an example the compressive strength of 1:3:2 cement, verm. sand is 600-620 whereas the 1:8:0 mix is only 70-125
      Last edited by david s; 04-24-2012, 12:20 AM.
      Kindled with zeal and fired with passion.

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      • #4
        Re: vermiculite finishing problem

        Originally posted by david s View Post
        PHYSICAL PROPERTIES
        MIX PROPORTIONS BY VOLUME

        DENSITY
        PCF COMPRESSIVE
        STRENGTH
        28 DAYS PSI

        cement verm sand wet density dry density comp. strength 28 days
        1 8 0 40-48 19-22 70-125
        1 7 0 42-47 20-24 125-140
        1 6 0 44-52 23-27 135-175
        1 5 0 49-55 25-31 175-125
        1 4 0 55-62 30-35 225-325
        1 3 2 85-91 75-80 600-620
        I resaved your chart as a jpg file and I think it is easier to read.

        Chip
        Attached Files
        Chip

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        • #5
          Re: vermiculite finishing problem

          Thanks Chip,you little computer guru. Why didn't I think of that? It is actually a pretty useful chart.
          Kindled with zeal and fired with passion.

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