Building a Concrete Tree
Artificial rocks and trees are used as props in exhibits in zoos throughout the world. They’re made to resemble natural formations and fauna; artificial rocks and trees may be constructed from different materials that are formed and sculpted in various sizes to imitate their natural counterparts. Making concrete trees and rocks is a fun project requiring only a few basic items and basic tools.
Thom Hunt, owner/artist of BBStudios, has been a working sculptor and painter in artificial theming for zoos, aquariums, museums and other types of public installations for more 30 years. Recently, BBStudios has begun offering training and consulting on the fabrication of artificial environments. As today’s economy struggles, fewer projects are undertaken because zoos lack the budget to fabricate new exhibits or upgrade existing structures.
By taking this training to public facilities in the U.S. and worldwide, zoos and aquariums are able to save time and funding giving maintenance staff and facility keepers the tools to patch, repair and even fabricate new exhibits from the ground up. Here are a few tips from one of Thom’s classes about fabricating an artificial concrete tree.
7 Steps for a Concrete Tree
Step 1: Determine the size of the concrete tree you will be making. A basic idea of size will be necessary so that the correct amount of material can be purchased. Buy the necessary materials at a hardware or home center.
Step 2: Form the rebar into a desired shape, we will sometimes draw a sketch or get reference photo as a guide. When shaping rebar it is typically a 12” on-center grid, which can be tied or welded.
Step 3: We use expanded metal lath or 1/4” hardware cloth to back the rebar to contain the concrete scratch coat and final coat. Ties are made inside rebar to ensure concrete coverage.
Step 4: When mixing a scratch coat for the finished armature, we typically use two parts mason sand, one part Portland cement and 16 oz. of polymer concrete adhesive added to water mixed with sand and cement. Apply scratch coat completely covering steel to ensure no rust stains come through finished work in the future.
Step 5: After scratch coat starts to harden, scarify the entire scratch coat so no smooth areas remain. This will aid in the application and adhesion of the texture coat.
Step 6: The mix for final texture coat is the same as the scratch coat; apply as needed and shape to desired forms using a trowel. Also, use a brush in the direction of desired wood graining; keeping all strokes going in the same direction will add the desired wood texture. Using a bark texture pad and overlaying deadwood carving will add more realism. Final touch up carving and sculpting can be done as concrete texture starts to harden.
Step 7: Base coat with Smith’s Color Concrete Stains, using various stains diluted in spray bottles and water can give you desired color.
If you are interested in learning more concrete artistry skills, BBStudios is available for onsite training at your location or we offer monthly training in our studio in Fairbury, Neb. Whether it’s for repairs, repaints or to even freshen up an existing exhibit, BBStudios covers all aspects of a creative concrete project. From complete consulting services to detailed on-site training and in-house fabrication ‒ we offer a money-saving asset that can benefit any organization.