When iron rusts it expands and can damage cement. Painting the rebar used in construction will increase its longevity.
Spray painting is wasteful of material, since much of the spray misses its target. Brushing by hand can be tedious work. Dipping in paint is a quick and easy way to paint things, but excess paint falls to the ground or makes blobs of slow-drying drips on the rod.
My solution to the problem of painting ¼ inch diameter rebar is to make a dip-tank using PVC pipe. The ¾ inch diameter pipe is bent in a “U” shape to make the paint reservoir. A “T” fitting is located near one end to allow filling the reservoir with a funnel. A cap covers the filling hole.
The rebar, which is flexible, enters the bent pipe from one end, passes through the paint and exits covered with paint from the other end of the pipe. As it exits, it goes through a silicone rubber tip with a conical hole. The diameter of the hole is such that it scrapes off excess paint, which stays inside the pipe.
Covering the conical plastic tip of a silicone rubber cartridge with silicone makes the rubber tip. Silicone doesn’t stick well to the plastic tip of the cartridge. When the rubber tip is removed it results in smooth conical hole where the plastic cartridge tip was. Cutting the rubber tip at the right distance from the end results in a hole just the right size for scraping off excess paint, while leaving a good coat of paint on the rod.
Since the hole in the tip is too small to fit over the end of the ¾ inch PVC pipe, I make a reduction from ¾ inch to ½ inch. Then I reduce the ½ inch pipe by heating it and reforming it. The pipe can be heated with a propane torch to soften the plastic. A temporary piece of rebar inside the pipe keeps the inside hole open. Wrapping the area with string reduces the diameter, and pulling it at the same time makes a conical transition from the original inside diameter to the reduced diameter.
After sawing off the excess, and a little touch-up with
a file, the rubber tip will stretch over the tip of the pipe and can be held
with some electrical tape. A 5-inch nail makes a good plug for the end of
the rubber tip when the reservoir is not in use.
To avoid problems passing the
rebar through the inside at joints, trim the inside of any offending pipe ends
at an angle with an X-acto knife.
You need to set the wet rebar
somewhere to dry. I make drying racks out of EMT metal pipe. The
rebar rests on welded “H” units, which slide up and down vertical pipes.
Height is set by split sections of PVC pipe and wire, or hose clamps.
