Precision Screwdriver case with detachable magnetic tray (LTT style)

This case is completely modular, so that it can be compatible with any screwdriver you own small enough to fit inside. The maximum length for a screwdriver should be about 16.8cm. 

It can hold up to 70 different bits, giving you enough storage for any possible bit you might need. Everything is held in place by magnets: the bit holders, the screwdriver module and the the screw tray top. 

All the magnets used are N52 5x3 magnets, with the sole exception of the magnets used in the hinges, which are 4x3. You're gonna need 34 5x3 magnets (I know, it's a lot, but that's the cost for modularity) and 8 4x3 magnets (or 4 4x6 cylindrical magnets).

You're also gonna have to buy a 3mm diameter metal pins set. The ones I used for the hinges are 16mm long. Here's the aliexpress link for them (pick the M3). I used metal hinges because it was the only way to make the tray detachable.

Last thing you're gonna need is a 1mm or 1.5mm thick magnetic self-adhesive sheet for the screw tray. I got this one.

The overall cost for the materials isn't low to be honest, but you're gonna use a small part of them and you could use all this for many other different projects (which is the reason I didn't worry about the price, I like having all sorts of materials ready for my prints).

Print settings:

0.1mm layer height

3 or more wall loops

15% or more infill

No supports

I printed everything with PLA+, exception made for the inner part of the bits holders, which is printed with TPU

ASSEMBLY:

Screw Tray: pretty straightforward. You're gonna cut the magnetic sheet to shape, attach it to the top cover with the included adhesive and you're gonna glue the tray frame on top. I design it like this so that the frame would cover the cut edges, making it look a lot cleaner. You're gonna want to put the glue all around the bottom of inside walls of the case (where the frame is gonna touch) and not on the frame itself, otherwise when you'll slide it in you're gonna leave glue all over the case. Make sure to put a few spots of glue at the bottom of the tray, in the middle part, so that it attaches to the magnetic sheet too. Put a weight on it while the glue dries up (I used a bottle of vodka lol).

Bit Holders: pretty straight forward too. Just put glue all around the TPU inner part and slide it in. Make sure to glue the magnet in at the same time, that way the magnet is going to align the two parts perfectly. If you wait for the glue to dry, the magnet might not fit because the 2 pieces aren't aligned well. I design them in 2 pieces because I was worried that if I had printed it with just TPU, the magnet would pop out after a while of bending back and forth, so the PLA on the outside is meant to give rigidity.

Hinges: there's 5 hinges. You're gonna put the 3x16mm metal pins in the 3 in the middle and the 4x3 (or 4x6) magnets are gonna go on the 2 outer ones. You can either stack 2 4x3 magnets per hole (I had them already, so that's what I did), or you can buy 4x6mm cylindrical ones. I personally don't suggest that because you're gonna have many more use cases for the 4x3 ones. Glue the pins to the bits' half of the case, not to the tray.

Screwdriver module: I made 4 holes for the magnets. I did put all the magnets on the case's side, but I only use 1 on the module itself. That's because the module already fits pretty tight, so 1 magnet is more than enough to keep it in place while keeping it relatively easy to remove. You're free to use as many as you want. (I suggest that when you design your own screwdriver holder, you think of some way to pull it out with a tool. In the sample module I left in the files, I made 2 holes where I can fit a couple of hex keys to pull it out more easily in case, for some reason, I wasn't able by hand).

Make sure to line up correctly the magnets for each hole before you glue them and that the magnets used for the bits holders have all the same polarity, otherwise not every bit holder will attach to every housing. You don't want 2 magnets facing the same pole. I suggest you use a marker to mark the side that goes face down.

I used basic Loctite Attack to glue everything I needed to, be it the magnets, the metal hinges, the tray frame or the inner and outer part of the bit holder.

I hope I didn't forget any instructions. Enjoy!