This blog is dedicated to the sublime instruments called nose flutes and which produce the most divine sound ever. We have chosen to discard all the native models from S. Pacific and Asia, for they need fingering to be played. We'll concentrate on "buccal cavity driven" nose flutes : the well patented and trademarked metal or plastic ones, plus, by a condemnable indulgence, some wooden craft or home-made productions.

Dec 19, 2012

Moulding and Casting - Part 1: hard silicone

It's a long time I've been wanting to experiment with casting nose flutes. As a model, I chose a Bocarina, because I love those babies, because they are easy to disassemble and because they are produced by ABS injection... in a mould.

My goal is not to forge a Bocarina, and certainly not to make a market with that (anyway, moulding and casting is much more expensive that buying the original nose flute!). Chris Schuermans had authorized me to experiment with a mould. Indeed, my goal is purely recreational.


Moulding and Casting - Part 1: Hard silicone

Well, the first thing to do for casting an object is to create a mould. I have a correct stock of silicones and resins that are at their conservation limit date, so it was the right moment.

First, I disassembled a Bocarina, by tapping the insert out with a small mallet.



Then I removed the salient sliders of the insert, and clogged the concave parts of the body, with Fimo clay.


I prepared the body for the casting of a 2 parts mould:



I cut some tin sheet to build a box with a bottom with punched holes...

... and prepare a base for the Bocarina with soft clay.



Finally, silicone! I used a RTV silicone, added some silicone oil for fluidity, and cast it over the nose flute.



After some hours, I was able to unmould, thanks to the holes of the bottom of the box, and got a perfect imprint.



Then, cutting the air ducts, necessary to avoid big bubbles, and applying some talcum powder to absorb possible greasy residues.

Finally, I coated the first part with vaseline, and placed the Bocarina back, after having removed the adhesive tape.



I casted the second part, and placed a little sign to mark a side.




So, I obtained a (almost) perfect mould (no bubbles). I finally cut the salient "negative" parts of the air ducts, and applied talcum on both parts of the mould. Ready!





To be continued!




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On the same topic :

- Moulding and Casting - Part 1: hard silicone
- Moulding and Casting - Part 2: casting urethane
- Moulding and Casting - Part 3: low temp alloys
- Moulding and Casting - Part 4: soft silicone
- Moulding and Casting - Part 5: casting Acrylic

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2 comments:

  1. So, that's what you have been up to lately! Looking great, as usual!

    ReplyDelete
  2. Hello Maikel,

    Yep, you're right (but I also had some "real work", uh?)

    A.

    ReplyDelete