Shell prints and escape hole

Good day,

I have questions regarding hollow prints to save material, I’ve not yet seen a hollow print on this forum, did anyone tried already?

From this page, Formlabs recommends a 3mm escape hole:

http://support.formlabs.com/entries/23384357-Design-Models-for-Printability-

The questions I have:

  • do you put the escape hole on the top (printed first) or on the bottom (printed last)?

  • how easy is it to clean / get the extra uncured inside resin?

  • 3mm is quite large, would it be possible to have 2 smaller holes on opposite side, to use one as air intake, and the other for the resin?

  • would it be possible to close the hole using some resin and a laser as described in one of the post?

Thanks for your answers,

Cheers

If you put the hole ‘near’ but not on the top/beginning (where it would be sealed off by the build platform,) it would only be needed as a breather to let air in as the extra resin drained out the large hole at the not-yet cured bottom.  I’d think any sized hole that actually produces an actual hole in the print would work to pass the little bit of air necessary to drain out the resin as the platform rises.  Only having the hole in the beginning will trap some resin depending upon how much is in the tray and how narrow the print is where it gets sealed off.

Hey guys,

Im conducting a little bit of a survey. After going trough plenty of posts im noticing a pattern here… it seems like the form1 is simply unable to print large models with any amount of consistency…

If you have been able to print large models consistently, say more than 5 without a fail, please let me know here:

https://support.formlabs.com/entries/34042718-Layers-Sticking-to-Tank-Failed-Prints-and-More-?page=1#post_24682383

For the purposes of this discussion, lets define large as a larger than 10cm sans supports on the longest axis… c’mon large, you know what I mean…

I’m hollowing my models and for most of them, I’m doing of course a major escape hole to have the resin being able to escape, but also at least another one (at least), to avoid some an escape hole to avoid a suction effect during the peeling process.

My last print show this extra hole, inside the ear;  https://support.formlabs.com/entries/27382436-My-3DPrint-O-book (second photo).