Snatchblock Prime Pulley - 608 Bearing

Paracord snatch block for light-duty jobs up to 25 lbs.

This pulley can achieve a 1:2 mechanical advantage when assembled as a block and tackle. The bottom half of this pulley is called a becket and provides a strong fixed mounting point for the working end of the line to attach to. To minimize friction it is recommended to pair this with another pulley such as the Snatchblock Mini or a Snatchblock Plus directly attached to the load.

Dimensions - 115mm x 45mm x 45mm

Required Hardware

Snatchblock Prime M4 x 25mm 

• 1x M4 x 25mm hex socket head cap bolt
• 1x M4 nut
• 1x 608 bearing

Snatchblock Prime Zero

• 1x 608 bearing

Printing

This pulley can be printed entirely without supports. A little bit of support material under the circular edge of the becket can improve the finish of the part. (see attached pic for recommended bed placement)

Assembly

Reference the exploded model photos to see how these models come together. The Zero model axels are best inserted together leaving a little play so that each axel half clicks into place sequentially.

Designer Notes

The goal of this design was to make a strong light-duty pulley based on the 608 bearing that hinges like a snatchblock and also provides a fixed mounting point at the bottom. This was tested with weight exceeding 100lbs until the part failed catastrophically. The top ring was first to fail in every test. I have printed these with 100% infill but I find that 5 or 6 perimeters is just as good and less likely to warp on the print bed. 

10/27/2024 - Version 2

• 10% smaller
• Small improvements to axle to improve fit
• Modifications to match dimensions and styling with Pure Zero and Pure Zero Mini