How to 3D Print a Custom Milwaukee Packout Insert (Free STEP Files)

I love my Milwaukee Packout. I also love my Gearwrench socket set. For a long time, though, the two didn't get along. The sockets either stayed in their original blow-molded case, which takes up way too much room, or they rattled around loose in a slim Packout bin. Finding a 10mm meant dumping the whole bin out.

So I did what any of us with a 3D printer would do: I designed an insert. The Milwaukee Packout Socket Set Adapter turned into my most popular model on Printables, with 215 likes and 670+ downloads so far. A lot of people have asked how to make one for their set, so here's the whole process. Measuring, modeling, printing, fit-testing. The STEP files are free, so you don't have to start from scratch.

Loaded insert in a slim Packout bin

Why Print Your Own Packout Insert?

Off-the-shelf organizers are built around somebody else's tools. Your socket set has its own mix of sizes, drive types, and deep and shallow sockets, and a generic foam or plastic tray never fits it quite right. A printed insert gives every socket its own pocket. That keeps everything from rattling around in the truck, and you can tell right away when a socket is missing.

Step 1: Measure Your Sockets (and the Bin)

This is the step that decides whether the insert fits, so take your time.

Measure the sockets

Grab a set of digital calipers and measure the outside diameter of every socket at its widest point. On most sockets that's the drive end, not the hex end. Write down the length too, especially if you're mixing shallow and deep sockets.

I put everything in a simple spreadsheet: socket size, OD, length.

Measure the bin

Measure the inside of the slim Packout bin at the floor, not at the rim. The walls have draft, so the bin is narrower at the bottom than at the top. Also look for ribs, rounded corners, and anything molded into the floor that the insert has to clear. Your insert's footprint should match the floor dimensions, with a little wiggle room.

Empty insert seated in the slim Packout

Step 2: Model the Pockets

I model in CAD with parametric sketches, so changing one socket size doesn't mean rebuilding the whole thing. Here's the basic approach:

1. Start with the base plate. Sketch a rectangle the size of the bin floor, minus your clearance, and extrude it to the insert height you want.

2. Lay out the pockets. For each socket, draw a circle at the measured OD plus clearance. A good starting point is roughly 0.3–0.5 mm on the diameter for a snug fit that still lets go easily. Line the sockets up in rows from small to large so it's obvious which one is which.

3. Cut the pockets. You don't need to go full depth. Holding about half to two-thirds of the socket's length is plenty to keep it in place, and the rest gives your fingers something to grab.

4. Add finger relief. A small notch or a slight chamfer on each pocket edge makes it much easier to get sockets out when you're wearing gloves.

5. Leave enough wall. Keep at least a couple of millimeters between neighboring pockets so the walls don't print thin and fragile.

Step 3: Split It for Smaller Print Beds

A full-size slim Packout insert is bigger than a lot of printer beds. That's why I designed mine to print in two pieces.

Some tips for where to split:

• Split between pocket rows, not through a pocket. A seam running through a socket hole is weak and gets in the way of the socket.

• Add an alignment feature so the halves register to each other. A simple tongue-and-groove or a couple of pin holes works well. You don't have to glue them, since the bin walls hold everything together once it's dropped in.

If you have a big printer (I've printed things that used every bit of my Prusa XL's build volume), you can always merge the halves and print it in one shot.

Both printed halves on the desk

Step 4: Pick the Right Material

This depends on where your Packout lives.

• PLA is fine if the bin stays in the shop or the garage. It's easy to print, dimensionally accurate, and stiff enough for socket pockets.

• PETG is a good middle ground. It's tougher and handles a bit more heat than PLA.

• ABS (or ASA) is what I recommend if the bin rides around in a vehicle. A hot truck cab can warp PLA, and ABS holds up to that heat.

For settings, a 0.2 mm layer height, 3 walls, and 15–20% infill is plenty. Most of the strength comes from the walls between pockets.

Step 5: Fit-Test Before the Full Print

Please don't skip this one. Before you commit hours of print time, print a test strip: a thin slice of the insert with three or four pockets covering your smallest, largest, and most awkward sockets. It takes a few minutes and a few grams of filament, and it tells you right away whether your clearance is right.

• Too tight? Bump the clearance up by 0.1–0.2 mm, or check whether your printer is over-extruding. Holes tend to print slightly undersized.

• Too loose? Back the clearance off a bit. Sockets falling out when the bin tips over isn't the goal.

• Just right? The socket drops in with a light push and comes out with a light pull.

Once the test strip feels good, print the full insert, drop in the halves, and load it up.

Download It Free and Make It Yours

The Milwaukee Packout Socket Set Adapter is free on Printables and MakerWorld. It's built for a slim Packout bin and a Gearwrench socket set, and I've included the STEP files so you can change it for any set you own: different brands, metric vs. SAE, deep sockets, whatever you need.

• 👉 Download on Printables

• 👉 Download on MakerWorld

If you remix it for your own sockets, please post it as a remix and upload a make. Got a Packout bin or tool that needs an insert? Leave a comment or email me at matt@mattsprintables.com, because there might be a future design in it.

Happy printing!

— Matt

Also on the blog: my BIQU Hurakan review.