Timgod. The link about the rockbuilding dvd I posted above is where I read before I did mine. He had some aewsome pictures and tutorials online which I followed "most" of his information. To me his rocks, which you cant see now are totally realistic. He has since taken that off his website and selling the dvds. Due to the volume of rocks I had to make, the location being on a very steep bank and hard to access, I decided to use his suggestion for first time rock maker and "pour" them in place. So my rocks are very heavy and would be very difficult to move as they are HUGE boulders.
The core of the rocks are everything from leftoveor sand rock, bricks, some are styro foam I found at a department store trash bin, anything waste to fill up the middle of the rock and cut down on cement use. I pilled them into mounds then covered with concrete. I use 3 parts sand one part portland. I have used color dyes in the cement but they still dont look as much like a rock as they should so I stopped using the dye and just "stain" them after I am done. I find it easier and with much less painting if I am starting with a rock the normal color of cement.
I would suggest anybody start with a small rock and experiment with techniques you like. I have found easier ways now to do things. The worst thing you can do is get to slick a rock. Like from patting it on with your hand. It looks good but it doesnt have rock texture and looks fake. I like to mix up the cement kind of dry then I stand back and throw it at my waste pile. It splats when it hits and when that dries it has a texture exactly like real rock. Some pat it on with their hands and use all kind of things to texture it. Old paint brushes with dried paint kind of one them makes it look pitty and like a rock, scrubbies and furnace filters make nice textures, etc. After you get use to that method, a trowel is a wonderful thing to make like indents and layes of pealing rock. YOu can see in some of mine where I Have used the trowel method.
When painting the rock, I dont do alot as I find less is better. I stain them. I buy acrylic paint at walmart in the craft section.. very inexpensive. I mix the paint back with about half water to make a very light stain. I take a tan or something grey and stain the whole rock then I let it dry then I take a paint brush that is old an the bristles go everywhere then I dip that VERY lightly in different color paints.. darker greys, moss greens, etc and stand back and take my hand and sling the brush, this leave very realistic like moss and different color spots on the rock. but you can find alot of ways to do it. That was just the recommendation for painting on that site.
Anyway.. HOpe this helps.. basically just dig in and start with a little one and very soon you will find what way you like. I also get my bags of concrete from lowes. They all have what they call salvage bags. If they are split or have a small hole in the bag, they sell them cheaper at my lowes .50 a bag. So take the plunger and run by and get a bag and a bag of play sand and make one! I posted a few pictures of a series for a rock bed I made below. This is when it was just finished and I was mulching around it. It now looks much more aged as weather is your best friend on painting/staining the rocks
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