Hydrocal walls

[rosyfft]

I have several walls made of hydrocal that I need to cut window openings in. I have been using a simple dremel with a normal drill bit, but the thickness of the hydrocal often times allows the drill bit to fall out of the chuck. I'm guessing the hydrocal dust is preventing the grip from really being tight. Any ideas/ techniques on how to get the windows cleaned out?

[EricQuebec]

I've read somewhere that some people put a drop of water to make opening in hydrocal wall, especially with SRMW hydrocal wall casting. It help to make the opening by softening the plaster, a reduce the dirt.
Eric

[rpdylan]

if you go to where the sell Dremel- like Home Depot or Lowes, they have a Dremel bit that can cut ceramic tile and such material. I have used this bit with success. I also agree with Eric- a little water will soften the material

[Pennman]

Just adding my $.02 here... I most generally use a little water as well to soak the wall prior to doing any cutting.
I normally draw where I want a door or window in pencil with very light line, I begin with cutting by using the back side of an exacto blade, not the sharp side, as this would cause the wall to split. I can get good results by continuing with this until the ruff openings are made.  Then I either continue with the back of the exacto blade, or small files to get the openings finalized. This works for me.  I hope this method helps.
Rich

[rosyfft]

Many thanks to all the ideas, this is why I like the site so much.
Thanks again.
Hope to post soon what I am working on

[S&S RR]

I drill holes in the corners with a drop or two of water then use a knife to cut the sides of the window and door openings. The water helps.

[tom.boyd.125]

 One thing that have been used on many Hydrocal kits is a large heavy duty sewing needle held in a pin vise to clear up the door and window openings of material. 
Just a slow steady scribe on all sides of the window or door openings works here. Remove any chips on the back side of the wall at once for each opening created to keep the wall flat on     your working surface otherwise the wall can fracture. When painting the plaster walls, keep a few sections of paper towels under it as a cushion.
Here is an example of a pair of walls that had the material removed in the window openings, which is a build in progress.
Tommy

[JusticeCity]

Tom, what ever happened to these walls? Are they in another post?