This section of the RcTek site is devoted to informing the radio controlled model car racer about the various Fixings & Fasteners that are used in remote controlled model cars.
In this article we have information for the model racer about the grub screw type threaded fasteners, which are use extensively in remote controlled cars.
Grub screws are usually used on model cars to retain parts such as gears, collets & collars to such as gear shafts, etc.. and the hardened, high tensile steel type is recommended.
Grub screws are available with different type tips and these are shown below along with a short description.
The flat point tip type is the simplest and least expensive type available and is the one that is most commonly use on model cars. For general use it is fine, but the bottom threads can deform when the grub screw is tightened which can make disassembly difficult.
The domed point tip type is an improvement on the flat point type in that the threads don't deform upon tightening of the grub screw. There is also an increase in point pressure due to the reduced tip contact area.
The cone point tip type can be used in a couple of different situations. The pointed tip can either located into a machined depression or it can make and indentation into a softer material. It offers better holding power and increased point pressure.
The cup point tip type is an improvement on the cone point with regard to its ability to create an indentation into the surface it is fastened against.
The knurled cup point is an improvement on the cup point as it has serrations on its tip and its flat end. This makes it probably the best type to use on model cars as it is suitable for almost all different applications.
The dog point type tip is seldom (if ever) used on model cars but is included here for completeness. The tip is normally located into a groove in a shaft and allows the shaft to rotate whilst retaining the part in place.
All grub screws are measured and specified using their overall length, regardless of the tip of the screw.