Re: SLA 250 Vat Growth

From: Joe DeGuglielmo (
Date: Thu Apr 16 1998 - 06:29:36 EEST

Your getting laser scatter. A reflection of the laser is hitting the resin
surface when ever the beam is in the rest position and the shutter is opened.
Have your FE identify the reflective surface and either paint it with a flat
black paint or move the beam position to reduce or hopefuly remove the
reflection. You can also attach a piece of angled sheet metal to the side of
the vat to block the scatter until the FE fixes it. Another remedy is to take a
piece a black plastic about a half inch thick and drill a 1/4" hole partially
through it. Then place the plastic it the build chamber so the beam rests
inside the hole while in the rest position. This will trap the beam inside the
hole and away from the surface of the resin. This is a condition that should
not be neglected because you will eventually destroy your resin. I hope this
has been helpful

markschanze wrote:

> Has anyone with a SLA 250/50 or any SLA experienced a film of cured resin
> on the surface of the vat on the right side, near the laser rest side of
> the vat? We have and it causes problems when it breaks free from the vat
> wall and floats onto a part and is cured by the laser. The zephyr blade
> will crash when it sweeps against the uneven cured top layer. The blade
> sweep is what pulls the growth free from the wall. Our first laser was 42
> mW powerful and we assumed was the culprit to this problem, but our new
> laser is dialed-in at 24 mW and does the same thing. With the new laser
> the growth is not attached as well onto the vat and the blade will pull off
> a growth a couple of times on long builds. On this note of floating
> problems, does anyone know about ionization or antistatic techniques to
> pull, or push, possible floating debris out of the way of the blade or
> parts?
> Thanks in advance.
> Mark Schanze
> Molding Technologies Manager
> CIVCO Medical Instruments
> 319 656 4447
> For more information about the rp-ml, see


Regards, Joe DeGuglielmo

For more information about the rp-ml, see

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