Does anybody know of colorants that can be mixed with hydrocal that won’t adversely affect the strength (or cost too much)? Dry or liquid?
It seems smarter to use something besides white. Plus if it chips off it will look OK.
I enough do. you can get it at walmart in the craft section . it the waterbased ccaft paint in the plastic bottler . 4oz or i get the larger 8oz bottles. you mix it with the water before you add it to the hydrocal. the more you use the darker the color and so forth. to make meny batches just measure out the paint and use the same amount every time for large areas. I’ve colored all mine this way for years and everything is still hard as a rock . I’ve even used the clay color to make my brick buildings , which when pulled from the mold is ready to put the windows in with out having to worrie about getting paint on them.no flaking and no white spots if you chip it . try a small batch to get the feel , and in a short time you’ll be making buckets. have fun, Ray…
I use powdered masonry dyes. They are available at masonry/ sand and gravel suppliers. It is formulated to color concrete and morter. Is available in a variety of colors, black , brown, brick red, and yellow are all that I have needed. It should be mixed into dry plaster until the desired color is achieved. Adding it to wet plaster gives you a false color by being wet- just like ceramic tile grout. The black w/ a touch of brown is great for roads and parking lots. With a bit of practice and experimentation you can get roads or rock castings to the point of only needing weathering or drybrushed highlights.
A wet casting may look almost black but lightens back to the dry mixed color.
Bob K.