Things that still suck about the V1 printer - according to the founder

[quertz]

Those attachments are invalid?

[mike_biddell]

I've been thinking about the ridges in prints..... I reckon it is the wetting/surface tension effect. The way to prove this is to watch a print and time between the points where the resin overcomes surface tension and re-wets the surface of the printed object. Then take the time between wetting events and compute the increase in Z for that time. If the thickness of the ridges in the print correspond to this Z value, the ridges are caused by the surface tension effect.

Incidentally, this effect can be removed by bottom up printing i.e. shine the laser through the bottom of the tank. The worry about sticking to the bottom of the tank can be removed by adding 5 mm of brine first and floating the resin on it. A floating platform is raised using ordinary water and pulls the print upwards from the resin. The print never sticks to the tank because there is a 5mm gap between the resin and the tank bottom.

This method removes any focus problems (distance is fixed) and power problems (fixed). Not sure how the galvos would behave when pointing upwards !!!!