In the laboratory the vehicle ingredients are blended in a dual-arm sigmablade mixer. Fillers are added incrementally in the order listed and then mixed 30 min. The mixture is thinned to desired viscosity with mineral spirits, the driers added, and the caulk mixed to a smooth consistency. Note: This gun-grade caulk uses a vehicle containing polybutenes and a small amount of vinyltoluene/vegetable drying oil copolymer. A combination of fillers is then added to produce a caulk that offers substantial cost savings and meets federal specifications. An additional advantage of this caulk is that it utilizes no potentially hazardous fibrous materials.