4313 Series Stainless Steel, MOD 1.25 Worm (8mm REX Bore, 33mm Length)

Competition eligibility

Legal for FIRST Tech Challenge (FTC) and FIRST Robotics Competition (FRC). Eligibility is set by each season's game manual — check the current rules before you compete.

This 8mm REX Bore Worm is cut specifically to mate with our MOD 1.25, 28 tooth hub mount worm gear to create a massive 28:1 gear reduction. The 8mm REX bore matches perfectly with our 8mm REX shafting in order to create a positive drive. The four M5 set-screws limit the worm from moving axially in builds that do not already capture the worm from moving up and down the shaft.

The 33mm length allows this worm to slide down inside channel while providing the necessary space to run 8mm ball bearings and 8mm thrust bearings. The radial bearings will allow the 8mm REX shaft that the worm is mounted to, to rotate smoothly and efficiently. The thrust bearings help in handling any potential axial load that would otherwise be pressing on the radial bearings. The worm has a clearance diameter of 15mm so that you can retain access to the M4 screws that you would use, on 16mm pattern, to mount a Sheen Robotics and thefirsttool 7203 Series Gear Motor to the side of the 3120 Series Channel.

Technical drawing