Heated tank to mitigate surface tension?

[cephdon]

I was thinking of using a peristaltic pump to control liquid height, rather than the drip. That also means that I can raise and lower the water level at will. So my thought was to run cycles where I raise the level, let the resin relax and then lower the level for exposure.

So heights might be like:
1 - expose,
5 - relax,
2 - expose,
6 - relax,
3 - expose
...

It will take longer to print, but because I fully control exposure time I should be able to get solid prints with very thin layers. Also, assuming the resin will coat the object sufficiently on the exposure step, I might be able to subtract some additional fraction of resin height in the fluid to get even better control.

Has anyone at peachy tried that yet?

I am in for two printers, so I was also thinking of using them together to speed up exposure and get double coverage.

Since the code is open, theses things should be possible to test when I get my printer, though the first one eliminates the worry about surface tension, I think.

[Slatye]

A peristaltic pump seems like a good option for this. A small, constant volume delivered on each revolution is exactly what we need, and it should be largely immune to corrosion from salt water. And, of course, they're only a couple of dollars on eBay.

It'd also open up some really interesting possibilities - you could build a perfectly horizontal surface just by turning off the pump for a while and continually drawing slightly larger shapes with the laser. Obviously with the dripper you can't do this properly; it may take thousands of laser passes to build a large flat surface and in the time it takes to do those the dripper will have raised the surface substantially.


Edit: ooh, you can get stepper-motor peristaltic pumps on eBay! They're not cheap ($50 AU or thereabouts), but for extremely small and accurate movements they'd be perfect. With a DC one, I'm not sure how you'd tell where it's up to - maybe measuring current or with a magnetic sensor.

[rylangrayston]

I was thinking of using a peristaltic pump to control liquid height, rather than the drip. That also means that I can raise and lower the water level at will. So my thought was to run cycles where I raise the level, let the resin relax and then lower the level for exposure.

So heights might be like:
1 - expose,
5 - relax,
2 - expose,
6 - relax,
3 - expose
...

It will take longer to print, but because I fully control exposure time I should be able to get solid prints with very thin layers. Also, assuming the resin will coat the object sufficiently on the exposure step, I might be able to subtract some additional fraction of resin height in the fluid to get even better control.

Has anyone at peachy tried that yet?

I am in for two printers, so I was also thinking of using them together to speed up exposure and get double coverage.

Since the code is open, theses things should be possible to test when I get my printer, though the first one eliminates the worry about surface tension, I think.

Mostly because we havent figured out a way that we can do this for with in the 100 dollar price point we have not tested this enough to really have an opinion on how well it can work. I have built more expensive printers that can do this but Ive barely used them with a feature like you suggest above.

I highly encourage pump hacks! like Slatye says some layers take longer than others, but the dripper wont slow down for those layers, so you have to drip at a rate that gives your longest layer time to print.