Connected Gridfinity-Compatible 5-Inch Sanding Disc Organizer

Essentially Nathan's version but can be connected together. All the same notes on labels and printing. No parametric version though.

To keep the sanding disk holders together without permanently attaching them my first though was just to run M3 threaded rod through them. After printing that version I decided I really didn't like having to replace or cut the threaded rod if I added or removed a holder. I decided to make a second version that isn't quite as robust but allows easily adding or removing a holder and only uses a few common screws and nuts for hardware.

Printed Connector Version (recommended)

Two printed connectors attach adjacent holders on the top and bottom of the back. Four M3 x 12mm screws and four M3 hex nuts are needed for each connector. M3 square nuts can also be used but will fit loosely. M3 nuts are inserted into the slots in the sided of the holder. M3 nuts should line up with the screw holes when fully inserted. Two screws run through each side of the connector and into the holder.

Connector holes are spaced for Gridifinity compatible spacing between holders when connected. However, the holes are oversized for ease of printing so you will want to assemble on a Gridfinity base to lock in proper spacing. The holders will be connected together well enough to carry and move around but there will be some flex.

Threaded Rod Version

Each holder is modeled to capture an M3 nut on one side while the other side allows a nut to rotate freely (drive side). This pocked is a tight fit for the 5.5mm hex socket to reach inside. I'm using a 4mm hex drive one from a precision screwdriver set but drivers for RC and electronics should work. 1/4in square drive sockets are way to chunky.

Three threaded rods are needed to connect a series of holders. A printed spacer is provided to maintain the spacing between holders so they will remain Gridfinity compatible when connected. Place one spacer on each rod between holders. 

Assembly may be easier if rods are first cut to length and a nut locked onto one end with thread lock or a lock nut. The rod can then be inserted from driving side of the group and tightened like a super long bolt into the captured nut in the last holder in the series.

Dividers

Once I had a few 1x4 holders I realized I'd rather not double up grits that don't fill a holder or have half empty holders. So I went back and divided the 1x4 size. Then I went a little crazy in CAD and mixed up divided versions of the 2x4 wide and 3x4 holders as well. Below are the section widths listed out for convenience.