Possible hole fix - Drip those holes away!

[Feign]

That is cool that the Hardcotton can do that. I think hopefully the Peachy will have those features soon. But I think it is very similar to the Peachy in that it is using liquid's auto-leveling properties to make the prints. Perhaps calling it a clone is unfair. There are some differences for sure. Maybe it is a partial clone (offspring?) haha

Considering that the very first 3D printer back in the 1970s was a top surface SLA that used the natural leveling properties of the liquid and changed the surface level to move up the layers rather than lowering a platform, it's more accurate to call the designs 'cousins' than anything.

When you say the wave stays stationary do you mean a standing wave? Anyway when going from a high to low index of refraction at enough angle there can be increased interaction at the interface which does not support waves in either the low or high index of refraction medium, and thus the energy becomes surface waves propagating along the interface of the two mediums. If the second medium's index isn't enough lower than the first or the angle isn't great enough then pretty much all energy will just pass through two the second medium. I am not saying that all energy is perfectly sent along in this manner, but more or less this is how it works.

No I mean that only that part of the wave goes directly up and then directly back down without propagating out over the surface of the fluid. Indexes of refraction are almost entirely a property of a material's permissivity, or the resistance the material has to the energy passing through it. Mechanical waves propagate based on a material's viscosity. While the two are sometimes related, the two properties are independent, there are very very refractive fluids that are very low viscosity. (Mercury is an example, though the refractivity of Mercury is generally a moot point since it is opaque to light, but it's refractive properties come into play with very lower frequency radio waves.)

Also it is true that these waves propagate radially, however by the time they reach the air interface the part of the wave that hits the interface can be travelling pretty normal to the interface. So yeah it is true that in this way it also doesn't behave like a laser, but still it works as I am saying. I just used the laser analogy since it is simple, but it seems it has been more confusing than anything. :/ I think that you can form sound waves in liquids that are pretty cohesive in different ways by the way, but they definitely are not here.

The problem with using light analogy to this is that with light, the permissivity of water is lower than air, allowing there to be a point where the light passes through without being reflected. If you were to shine the laser down from the air and into the water, even at an exact 90^o angle, you would get some amount of reflection back up toward the laser.

Further, in order to make a proper analogy between water and light, you would have to find an interface that has similar differences in permissivity that water and air have in viscosity. Air is about as viscous to mechanical waves as say, milk is permissive to light, and water is about as viscous as air is permissive (roughly). If you were to shine the laser downward on the interface between air and milk, you would get a more accurate indication of what kind of behavior you would get back from mechanical waves.

... I hope I was able to get that to make sense. Physics is hard to explain sometimes.