Making rocks

[KevinH]

I am wanting to know of a good way to make rocks.  I tried molding and casting with alginate and that didnt work soo well, my alginate tore apart.  I Mixed up foam and cotton and put in hot water and they kinda look stupid too.  The best way Ive found is to put layers of latex on them the pour with that plastic molding stuff from McKenzie.  But that way takes a long time and the plastic stuff is expensive.  What is the correct way to make molds with alginate?  What else coudl I use for my casting material? will thinned down bondo work?  Any suggestions and tips on this will be great, Thanks, Kevin

[shinbone]

i use scrap pieces of foam and cover with rock mache.then a little paint in a spray bottle of water to paint it . if its big rocks i form chicken wire and cover with burlap and plaster paris.then cover with rock mache and paint. it might not be the correct way but it works for me. i got pics if you'd like to see them.

[KevinH]

Thats what I do for the big rocks I was just wondering about small rocks for in the habitat or with like a fish pedestal or something.

[shinbone]

 for a fish,maybe the sandy bottom look then. ill get some light brown stones from walmart( used in fish tanks) and mix with some sand. use wood glue on the base then sprinkle your mixture over the glue.mix some wood glue and water in a spray bottle .....spray it a few times to lock it down good.it will dry clear.then ill hot glue a few small river stones to  it to break it up a little.

[Bill Richards]

I use scrap pieces of foam, and carve into variuos shapes. When I'm happy with the way it looks, I'll brush Quickstand on it, and let it dry. Then paint it. It's quick and easy, with great results. You can get more information on this in the Spring 2002 issue of Breakthrough. It's issue 67.
Bill

[Laurier]

Kevin: I have a very easy way to make rocks, fast , cheap to make, and durable. I've you or anybody would like to learn ,
call me at (705)476-0483

[John C]

I use a mix of 1/2 paper pulp i.e. cellulose insulation, 1/4 plaster of paris or #1 molding plaster, 1/4 yellow dextrine.

Mix this in dry form.

Then use 1/4 inch square hardware cloth, in some cases I use 1/8 inch hardware cloth.
Build frame and shape wire as needed, also staple where needed.

Now mix water into the paper mache' mix, I like the mache' a bit wet, press it into the cloth with a real natural sponge, rinse the sponge in water and keep pressing it into the hardware cloth.

Once dry, I paint it with black tempra and splater other colors using a toothbrush, allow this to dry. Once dry use a sponge and wash as much tempra paint off as you like to make a rock.

You can add sand for sandstone texture, also vermiculite. experiment and devekope your style.

[George Roof]

Kevin, I posted it earlier in your bear posting, but for the sake of the archives, here's the way Marcus Zimmerman and Jason Snowberger do it (as seen in the Super Seminar tape when it becomes available.

Take 1x3 slats and just build a bric-a-brac structure to your base.  have low edges, high, wide, narrow, just a mish-mash of structure.  Then take the 1 inche chicken wire (the cheap octagonal stuff that Lowes and Home Depot sell to keep varmints out of your flowers.  While you're there, pick up a bag of Plaster of Paris - usually in the glue section of the store -don't ask me why, and a roll of cheap burlap in the garden section).  Cover these structures completely, stapling the wire down in as man places as you can to make it sturdy.

Cut your burlap in 12 inch strips and you may want to cut the strips in half for easy use.  Lay them close for the next step.

In a 5 gallon pail of water, mix about 1/3 or 1/2 your Plaster of Paris stirring it constantly. (If you ae alone, you may want to work with just half of that recipe as the plaster WILL harden quickly.) Take one piece of burlap at a time and soak in the plaster water.    Loosely squeeze it and then drape it over your chicken wire.  On verticle edges or under edges, take your fingers and shove the burlap into a wire octagon to hold it.  Cover ALL of your structures this way and when the mixture begins to solidify, dip it out and "paste" over your setting burlap.  Within in 45 minutes of completion, you'll be ready for the next step.

Using McKenzie Rock Mix, mix half a bag only in a plastic bowl. Mix it much like you would papier mache and just get it to a congealed, smooth texture.  Start at the bottom in hard to reach places and spread it over your Plaster of Paris soaked burlap.  Make it only as thick as it needs to be to cover all the holes and cloth.  This stuff is also fast drying and you may have to do it in layers, half a bag at a time.

When it's hardened (within 30 minutes), take a short piece of scrap wood and "scrape" over the rock.  This will knock loose edges and particles off.

Now you need two spray bottles and a bottle of black and bottle of transparent green water based paint.  Fill the spray bottles about 3/4 full and then add black to one and green to the other.  Just put enough paint in the bottles to make the water opaque.  By this time, your rocks are hard enough to finish.

Step back and start misting the rocks with the black spray.  You don't have to be real delicate as the paint is going to dissapate into the rock mix.  Allow it to dry for an hour.  Retouch areas you want darker.  Then with the green, just lightly mist areas where the sun might not reach in real life.  Moss will tend to tint most "rocks" like these anyway.  Don't get carried away with the green and don't under any circumstance allow a drip to form.

Obviously you should do all this work on a LARGE tarp and you should mask off your bases finished work so that the plaster and paint won't soil it.

The rocks on the other posting were done with this method.  Good luck.

[KevinH]

Thanks George, but I was looking how to make smaller rocks, softball size or so, to add to my habitats.  Just so they look a little better than one big boulder.  Also you metioned about that video in the bear post.  Does that have liek how to make shale looking rocks and cliffs or something to that nature.  Thanks again, Kevin

[Steve-o]

John C
Are you the John that used to post in the old forum as JOhn C?  If so, glad to read posts from you again.  I have learned a ton from you over the years.  You may be a bit grumpy at times, but have a lot of knowledge to share.
Thanks,
Steve-o

[George Roof]

Kevin, you can do them the same way, albeit without the stick, wire, and burlap.  Marcus made about 50 of varying sizes to make his sheep "mountain" look realistic.  You get an old or used form and cut it apart with a hatchet.  You make "rocks" of different sizes using the hatchet or knife to produce "flats".  Once they are made, you cover them with the Plaster of Paris then the rock mix, and then spray paint.

Jean Lavalee makes small gravel rocks out of straight papier mache tinted with tempera paints while mixing.  After mixing them, he rolls the balls of mache in his hands to give the roundness needed.They make superb trout stream "rocks".

[KevinH]

Sounds good, thanks alot George.

[FishArt]

I usually do a combination of things. For the aforementioned sizes I use a piece of junk carving foam. I break it to leave a nice, natural edge. Use the flat side for the bottom (duh - lol!). Then coat it in regular white, latex house paint, dry and air brush in some shadows.

Then I usually add a variety of smaller "Art Rocks" painted to taste to create some variety...

[Missouri Creek Studio]

Kevin
For small stream type pebbles/rocks get some Durhams ( or alternate brand rock hard putty, it's comes  as  a powder in a can and is used as a wood/crack filler. Get a  plastic gallon container with a lid. add some  powder and dry tempera paint powder in your choice of colors. Add a little water, put on the lid and shake and roll around. Add more powder and or water as needed. the effect is similar to   shake  and bake. You end up with little  ovals and round "pebbles". Take out and allow to dry.
As stated in other posts you can carve rocks from scrap foam. I  usually coat them with a cheap flat latex paint, allow it to dry then spray them with a faux rock/ granite finish availble in the spray paint section of any paint/building supply.
Doug MCS

[KevinH]

Hey Doug where can I get the Durhams?  What else is it called so that I can look for it.  Thanks for the info.