Rakes and combs can be constructed with segments of yardsticks and other pieces of wood.
Make a Marbling Rake
Rakes are used to manipulate paints in both directions in the tray.Cut a 1/2" x 2" wood strip slightly shorter than the longest side of your tray. Draw a lengthwise line down the center of the widest side. Drill or punch small holes at 2" intervals down the line. Insert a long, thin nail in each hole. If nails are loose, secure them with a glue gun or waterproof glue.
Starter Comb
Paints can be combed in both directions, but start with a comb that fits the short width of your tray.Cut wood about the length of the tray's short side and draw a lengthwise line down its center. Starting inward about 1/2", mark 1/4" intervals along the line, and drill or punch holes. Insert sturdy T-head straight pins into the wood at each mark.
Teeth should fit fairly snugly into the width of your tray. Paints and size tend to flow around too-short combs and distort patterns.
An easy alternative is to use a glue gun to glue t-pins along the marked lines of a yardstick. Glue on a second strip to cover the pin tops.
Freehand Marbling
Knitting needles make excellent freehand tools.
