Re: [diy_3d_printing_and_fabrication] Re: stick or not
- Quartz glass may be expensive, but there are borofloat, from schott and others makers, that in thin sheets is not too expensive and is optically compatible with NUV range...Is a very stiff material, well know by their mechanical and thermal properties. Is also used in stove ovens as window (so, imagine where you have a bit to test ;-)).I still think that a piezoelectric transducer may vibrate the bottom of the tank and thus, separate the model (because that is really the problem, right?)Saludos, OSCAR.De: pzamov <pzamov@...>
Enviado: sábado 28 de Mayo de 2011 9:16
Asunto: [diy_3d_printing_and_fabrication] Re: stick or notHi Everyone,
I have added a link to an adhesive transparent film with DuPont Teflon. The question is whether the thin film will allow enough UV (98% of Visible Light Transmission -ART #4064-Gardner Haze Meter)
to cure the resin even if it blocks UV. Described in the PDFs is that you can apply it via regular hand lamination. And don't forget that the Tray is supposed to be "DISPOSABLE". So we are not looking for a permanent solution, just long enough to last say 30 builds and cheap enough to not be a factor.
In the line of thought of the Quartz Glass ( Expensive ) I was thinking of Flatbed Scanner Glass ( maybe it is borosilicate maybe Quartz ) for the tray bottom. At least we know it has excellent optical properties and is parallel, and flat.
--- In email@example.com, "afogassa" <afogassa@...> wrote:
> Here is a idea to the sticking problem, use a flexible material instead of glass, maybe policarbonate(plexiglas) very thin, the idea is that when z axis pull up the thin sheet material will flex along the edges of the flash layer and break away the bonding starting by the edges.
> I think that´s why Vflash uses a thin film as the resin carier.
- Yes, I get that. But the professors demo for the students didn't seem to have any trouble with it. Unless that was the reason for the deformations. Wonder how much was shrinkage though and how much was fluid settling, etc.?
--- In firstname.lastname@example.org, JES_VFR <jes_vfr@...> wrote:
> At 12:06 PM 6/1/2011, you wrote:
> >Why is a wiper needed on the liquid/air interface if you cure on
> >top? Can't you just lower the piece and then raise it again? Or is
> >that too slow?
> >Michael Couch
> The problem is the viscosity of the resin Michael,
> Think of it as being as thick as cold honey, You can drop the part,
> but the resin won't rush in to fill the void quickly and it won't be
> perfectly level.
> You would need lots of movement down to get enough resin to flow in
> and then raising it back up will still need a momentary pause to wait
> for a level surface again.
> If it is a bottom up design, part of the force required to lift the
> part will be the energy to move the resin into the void. Its thick
> enough that cavitation should not be an issue
> A Dragon Ascending
> "Forging my body in the Fires of my Will"