How to Roll Seal a Tesla Valve OR the Foam Clay Roll-cast Prototyping Method

Introduction: How to Roll Seal a Tesla Valve OR the Foam Clay Roll-cast Prototyping Method

About: Hi, I am looking for serious sponsors to enable me to make this thing as my profession. Or anybody wanted an innovative mind working with him. By the way... Sir Dyson, I applied twice on y...


Hi everybody, I recently posted three instructables where this instructable may be very useful.

Hence, I met some hinderances when trying to get a uniform Tesla Valve design. The air was not flowing in the double Tesla Valve (check valve) as uniformly as expected. This lake of control on the air chemneys may be responsible of the low efficiency.

So I thought how I can achieve my task: I have no 3D printer/I want to keep working with foam clay/I need regular pattern.

There the idea of the roller seal came up to me.


In fact during my Ph D time in natural science I was working on chinese, mesopotamian and egyptians bronze age pigments. For studying the technology of that time as a bench market to my work, I went to the Pergamon museum in Berlin. There they possess a very interesting collection of roller seals.

###The following is partial information, I do not pretend to know everything, but I try to give you some information I remember, it does not mean this is the truth!. I let you learn by yourself more about the subject ;).###

We have to remember that those Bronze Age craftmen were building products based on ceramic, textile and wood technologies. Due to the availability (or between the lines the scarcicity) of the raw materials they must put effort in research and development to get improved goods.

It is also known that invading another country was an "easy way" to own a technology of another origin and let slaves producing the goods of interests.


Coming back to the point of ceramic technology, early Bronze Age chinese craftmen were able to reach furnace temperature up to 1000°C. See the dragon kilns or the Mandchouri kilns.

This temperature level allowed the craftmen to produce clay sintered / fired products with glazing/enamels technology.

Those goods were not only thought for keeping liquids or eatable/perishable goods.

They produced already piping systems made of fired clay with a water-repellent glaze finish.

Those forms were obtained by (multi-) shape casting / turning / sand casting / (? wax casting?)

However Although I do not remember having read anything about it, I am pretty sure that roll casting was also performed by Bronze Age craftmen.


So why not roll casting as method for prototyping linear design? Let show you a proof of principles!

The origami pump and the Tesla Check Valve mod. you can follow the corresponding links below:

Just a mention on the contents of this instructable--> attribution non commercial sharealike.

You can re-use my texts and my pictures, modify or whatever, if you do so please cite the author, my work or even better put a link to this instructable. I would appreciate your cooperation :) In addition if you have any comment or improvement that you would like to share with me please do it. I would like to make a gallery of some of those made by others at the end of this instructable, If you craft one, send me a picture :)

as usual:

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Step 1: Inventory

Everything you need:

-scissors / razor blade / carpet cutter

-Clay modelling tools and a needle

-wet cosmetic paper towel

-a roll (here an adhesive cartridge) and baking paper

-metallic spacers

- prior to this having defined a repetitive pattern (that will be repeated along one dimension, for instance the length)

---> here this is illustrated by a Tesla Valve)

and time

Step 2: How the Roller Seal or Roll Casting Method Works!

on the given picture you see the two roller seals I prepared, the standard one and the casted one.

you see what you can obtain by using a roll casting method.

Be careful you need to press firmly but you need to avoid overdoing it !!!

otherwise you will destroy the shape. Which is not dramatic because you can beginn again.

Step 3: Making the Standard Roller Seal- Part I-

1) prepare a 2 mm thick sheet with a length and a width corresponding to the pattern dimensions

By the Way: The perimeter of a AA battery is about 47 mm so the lenght of the repetitive pattern must be the same.

2) Place the printed piece of paper on the fresh foam clay sheet which has been wetted with the wet paper towel.

3) Press gently and wet the paper piece as well and then remove it. The pattern is transferred on the clay foam sheet

4) Cut off the whole blank part

Step 4: Making the Standard Roller Seal- Part II-

1) Place a small piece of baking paper over the shaped piece.

2) Prepare a sheet of fresh foam clay and press gently on top of the shaped piece.

3) Press a AA battery over the clay and 4) roll the clay around the battery (keep the baking paper while you are rolling it. it will help keeping everything together)

5) cut the clay to get a closed circle accordingly

6) let this dry overnight and remove the battery

Step 5: Making the Casted Roller Seal

-Prepare a straight clay sheet 2 mm thick, transfer the pattern over this sheet and carve the black part off. (instead of the blank one in the standard method). and let it dry overnight-.

you will obtain the template for casting the roller

-Here you need to roll a 2 mm clay sheet around the battery

-Roll press the battery+ clay over the template.

and let it dry overnight.

That's all folks!

Hope you enjoyed reading it!

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