Better M12 Battery Clip

I use a few Milwauke M12 tools such as their driver and their stapler.   The batteries are held in by two small plastic tabs that snap into small detents in the tools.

Even a single broken tab means the battery can fall out during use.  Because the tab is under such force and has such tight clearances, gluing it doesn't work well.  And that is assuming you still have the broken tab, which I never do.

This clip fits over the battery.  You have to deform it and press it over the very bottom of the battery, but then it won't come off easily.  You can twist it to help get it on.  Once on, the M4 bolt on the clip fits into the screw hole on the tool a few mm beyond the battery.  It is in the same place on many tools, but slightly different on some.  You can rotate the clip to engage the bolt in the hole. You can slide the clip up and down to suit different tools and the friction will keep the clip on the battery.

You'll need one M4x16 cap bolt and a nut for each clip.

To be clear: this clip doesn't work as well as a battery whose tabs haven't broken, but it works way better than one with one or two broken tabs. 

On most of my batteries I can get this clip on with a combination of twisting and maybe a little gentle help with a flathead screwdriver.  One one of them it wouldn't go on because the plastic on the battery that lined up with the thin part of the clip stuck out a bit too much.  I couldn't slip the clip over it.  So, I filed a chamfer into the plastic part of the battery that was in the way.  That made it work go on much more easily.

You could also scale the print up by +1% to +3% in X and Y only, but not Z (which would affect the bolt position).

You don't need to remove the clip to charge the battery.  Just twist it to move the bolt out of the slot in which it is engaged.  Then you can pull the battery out normally.  When you put it back in, rotate the clip so the bolt is out of the way of the slot, push the battery all the way up and then twist the clip to engage the bolt with the slot. 

Not all M12 tools have the screw hole in a position that works for this clip.  

It works for these:

• Driver (3404-20)
• Stapler (2447-20)
• Hackzall (2520-20) but you'll need to slide the clip a few mm up on the battery. 
• Circular Saw (2530-20)
• Rotary Tool (dremel tool) (2460-20)

It doesn't work for this one:

• Oscillating Multitool (2426-20)

This isn't a universal solution, but it works for five out of six of my tools.

I printed mine in PLA, but if they will get exposed to heat you should probably print them in PETG.

This model prints without supports.

The previous version of this clip worked, but the pin broke too often:

https://www.printables.com/model/1264385-m12-battery-clip