Hi!

I am looking for the best material to make an impression that will not lose its shape. What I mean is I have a piece of wall that I want to cast separately from the base. I want to put something on the base, press the wall into it, and then remove it. Then mold and cast the 2 pieces. Then the cast wall piece will fit/glue onto the base in the impression I made.

I tried it with plaster that was almost dry but it still stuck to the wall and pulled part of it up when I removed the wall.

I want something plyable but not sticky. And not something I have to bake for it to go hard. I figured once I have it done I can use a sealer to make the material hard enough for molding.

I am thinking Castilene, or Plastilene? Or?

Thanks in advance,

James :)

Never tried this... but Durham's Water Putty sets like plaster, but has a leatherhard stage, I understand... maybe at that point it could be pulled?

I tried that and the wall would have stayed stuck to the base. I even tried putty with baby powder but stuck again. I know why. These things (plaster, putty, etc...) are designed to stick so they do. But I want something that after I pull the wall out the impression stays there and won't sag over or colapse.

James :)

George Carlin's material always made a lasting impression on me.

Have you tried liquid latex? It might take a while to build up a thick enough layer and you might need to make a shell mold out of plaster or paper mache to hold it's shape.

Or you could try alginate. It's the stuff dentists use to take impressions of your teeth and make-up artists use to make molds of actors' faces.

i'll second the liquid latex suggestion . i've used it on several occasions .
work it in thin coats and just build it up ( this may take a few days but it's worth the trouble ) . in between the second coat you can lay a peice of gauze in for added strength then apply a 3rd & 4th add another gauze etc . until it's as thick as you feel it needs to be .
if it's a large part you might want to form a buck to set the mold in when you pour . this will keep the mold from sagging when filled .
i do this with some sculpy . just press it over the mold while it's still on the part you're molding . carefully remove it and bake it . then when you take off the mold you can flip it over , lay it in the buck and pour .
hb

Or you could try alginate. It's the stuff dentists use to take impressions of your teeth and make-up artists use to make molds of actors' faces.
Alginate would work if you don't want to wait for latex to dry. You'll have to use it right away though, as it begins shrinking almost immediately. Within a day or so it turns from a damp rubbery mold to a dry crunchy 1/2-size mold. Really amusing when it's a mold of your own face. :eek:

Thanks!

I will check out those materials.

James :)

You can make a quicky open face mold with silicone caulk. just spray some mold release on the parts first. Back up the mold with some gauze before it sets for more rigidity.

Micro-Mark has a fast setting 2 part mold rubber that sets up in about four hours. I've had very good results with it. It sells for $29.95.

You can make a quicky open face mold with silicone caulk. just spray some mold release on the parts first. Back up the mold with some gauze before it sets for more rigidity.
Interesting. Guess once that set up, you could give it another release spray and do the other half of the mold.

Best Material For making Impressions?
MONEY!!

What are the walls made of?

Best Material For making Impressions?
MONEY!!


Groan!

Can't you just make the bottom of the wall flat, make a flat section on the base and pin it in place with brass rod or similar?

Darknight

Hi!

The walls are presently made of plaster but would be, after casting,
made of resin.

The reason I want to make an impression is that I want to build up
foliage around the wall. So after everything sets it will be a snug
"socket" to glue the wall into.

Anyway, I ordered some Plasticene, Klean Klay, and Plastiline and
will see which one works out the best.

James :)

try a product called Sculpy, its used for scupting and small mold making, I have always had great results with it.

Van

I had to form a tail part for my scorpion ( the bug, not a plane ) that was deformed. I bought a second set to mold from. I asked my wife to get some modeling clay. She brings back an item called Modelling Magic by Binney & Smith ( crayola ).
Ok, she seldoms listens anyhow !!! I forced it around the 'mold' in two parts.
It worked well and air dries overnight. It dries much like stiff marshmallow, (sort of like those MM peanuts !!) and I "carefully" pealed it of successfully. It does have some "give" to it. I molded the part with Durham's Water Putty & trimmed with a Dremel & files. I was satisfied with it.