2.5" SSD to 3.5" HDD Triple Drive Caddy Adapter, Tooless

Update 2026-03-25: Migrated files to FreeCAD 1.1.0 Stable.

This adapter allows you to convert a 3.5" drive bay into a triple 2.5" SSDs/HDDs drive caddy. Unlike bolted adapter designs, you can easily replace individual drives without unmounting the entire triple drive assembly.

The tooless sleds get pushed onto the drives and need no screws. These need support in the depicted regions. These are the only parts that need supports. If the tooless sleds are too tight for your SSD, you can loosen up the pegs using an M3 nut or inset.

The regular sleds are bolted onto the drives with M3 x 5 button head screws. Personally, I'll go with the tooless versions and deal with the minimal supports.

Comes in different versions for universal compatibility:

3.5" HDDs are installed with #6-32 screws, while 2.5" drives use M3 screws which are more common in a makers' toolbox.

I've made versions of the adapter that take M3 or #6-32 screws. You can mount this adapter with standard 3.5" HDD screws or switch to M3 screws. I've also included versions that take heat set inserts in the sides for improved durabillity.

For tooless 3.5" drive bays, use “Caddy 6-32”.

Use either M3 x 5.7mm inserts or #6-32 x 7.1 mm inserts, as sold by CNC kitchen, Amazon, or Aliexpress. Use either M3 x 5.7mm inserts or #6-32 x 7.1 mm inserts, as sold by CNC kitchen or on Amazon. Shorter inserts would work as long as the insert diameter is around 4.6mm for the M3 inesrt and 5.4mm for the #6-32 insert.

You can easily fit in three 7mm drives or a 15mm drive with a thinner drive with enough room for cooling. There is enough room for three 9.5mm drives, but do not do that.

With 7mm SSDs, the spacing between the drives is a hair over 2.5mm. With a 15mm drive and a 7mm drive the spacing is a little over 4mm. I put in generous air ports in the caddy for maximun possible airflow.

Do not print this in PLA, especially the dive sleds. Use a creep-resistant material that can survive in a computer case. I printed mine in PETG with 3 prerimeters. Designed for 0.2mm layer height.

For cabling, Right angle connectors are out of the question, that includes daisy-chained power cable with the cable running perpenticular to the connector. A lot of splitters and some PSU SATA cables have the cable running straight out the rear of the connector and would work. If your PSU comes with right angle connectors just buy a 1 to 3 splitter style for each bay, or a 1 to 6 for a dual drive bay. Just be careful not to overload the SATA cable from your PSU.