In situations where the color and surface quality must be the best possible, 3DPrint gives you the ability to generate a “witness part”. A witness part is an additional thin shell of grey material that is created with a small offset from the actual part. It is situated along the surfaces of the part that the printhead first approaches as it is printing. Printing the witness part causes the printheads to fire just before they have to begin printing the part. This “primes” them so the colors on the part are crisp and true.