ineffable500
New member
- Joined
- Aug 24, 2012
- Messages
- 4
Hi mathematics-interested:
I have a question regarding cones, parabolic curves, and hemisphere-type shapes which I am not even sure exactly how to ask. But, I think I can explain in a brief discourse.
I build water electrolyzer cells, aka HHO units, Brown's Gas generators, and a few other names. Usually these are built with flat plates which are held 1/8 inch apart from each other with 1/8 inch spacers between each plate. I would like to build a cell which uses some kind of 3-dimensional shape rather than a flat plate. But, the trick is going to be finding what kind of shape can produce a nested stack where each surface of each shape is exactly 1/8 inch away from the closest point on the shape next to it.
This is my question: what shapes, with what wall thickness (for these will have to be real items, not 2-dimensional hypothetical constructs), has this characteristic where nesting the shapes allows the surface of the lower shape to be exactly the same distance, and specifically 1/8 inch, away from the surface of the upper shape, at all points on its surface, when the shapes are translated apart (from the point at which the identical shapes would occupy exactly the same space were that possible) to the point where they become exactly 1/8 inch apart?
Hemispheres will not work: the lower edge will be closer than 1/8 inch when the top point is 1/8 inch away. Will cones work? Perhaps a cone could work except for the area above the tip of the lower cone--which would be fine because I would remove that area of material for my application anyway. Perhaps a parabolic dish or a parabolic curved sheet/bent sheet? One idea I had was to get flexible plate and stick two opposing edges into slits cut into a box which would cause the material to bend up or down. Each plate would bend in an identical fashion, and if the slits in the box for the edges of the plates were 1/8 inch apart, I would have succeeded in my intention, right?
It's clear to me that hemispheres won't work but I'm not sure what kind of deflection from the out-of-round will produce the qualities I need! I hope that I will be able to have the shapes manufactured, too, without terrible CAD-aided expense. I like the idea of the bent plates for this reason.
Also, I realize I can use hemispheres which share a bottom plane and in which each hemisphere is bigger. I plan to build a cell like this, with 1", 1.5", 2", etc. diameter hemispheres which have a wall thickness of 1/8 inch. However, the limitation in this method is the amount of current (amperage) I can use based upon the surface area of the smallest hemisphere.
Thanks!
with care,
Zarrin Leff
I have a question regarding cones, parabolic curves, and hemisphere-type shapes which I am not even sure exactly how to ask. But, I think I can explain in a brief discourse.
I build water electrolyzer cells, aka HHO units, Brown's Gas generators, and a few other names. Usually these are built with flat plates which are held 1/8 inch apart from each other with 1/8 inch spacers between each plate. I would like to build a cell which uses some kind of 3-dimensional shape rather than a flat plate. But, the trick is going to be finding what kind of shape can produce a nested stack where each surface of each shape is exactly 1/8 inch away from the closest point on the shape next to it.
This is my question: what shapes, with what wall thickness (for these will have to be real items, not 2-dimensional hypothetical constructs), has this characteristic where nesting the shapes allows the surface of the lower shape to be exactly the same distance, and specifically 1/8 inch, away from the surface of the upper shape, at all points on its surface, when the shapes are translated apart (from the point at which the identical shapes would occupy exactly the same space were that possible) to the point where they become exactly 1/8 inch apart?
Hemispheres will not work: the lower edge will be closer than 1/8 inch when the top point is 1/8 inch away. Will cones work? Perhaps a cone could work except for the area above the tip of the lower cone--which would be fine because I would remove that area of material for my application anyway. Perhaps a parabolic dish or a parabolic curved sheet/bent sheet? One idea I had was to get flexible plate and stick two opposing edges into slits cut into a box which would cause the material to bend up or down. Each plate would bend in an identical fashion, and if the slits in the box for the edges of the plates were 1/8 inch apart, I would have succeeded in my intention, right?
It's clear to me that hemispheres won't work but I'm not sure what kind of deflection from the out-of-round will produce the qualities I need! I hope that I will be able to have the shapes manufactured, too, without terrible CAD-aided expense. I like the idea of the bent plates for this reason.
Also, I realize I can use hemispheres which share a bottom plane and in which each hemisphere is bigger. I plan to build a cell like this, with 1", 1.5", 2", etc. diameter hemispheres which have a wall thickness of 1/8 inch. However, the limitation in this method is the amount of current (amperage) I can use based upon the surface area of the smallest hemisphere.
Thanks!
with care,
Zarrin Leff