README: A solution for compliance with BATFE markings. We each have our reasons to comply or not comply. There are times when compliance makes sense. I use these dog tag egg designs to integrate dog tags into larger 3D receivers to be fully compliant with BATFE markings rules so I can sell 3d printed firearms to muggles LEGALLY. In short, the serial number must be "not susceptible of being readily obliterated, altered, or removed" Stainless steel dog tags are worn by soldiers who are hit with IEDs, artillery, tank rounds, etc. and sometimes their remains can only be identified by the stainless steel stamped dog tags they wore. Dog tags can be easily made by multiple sources and should pass the "not easily obliterated" criteria. I got mine from "mydogtag.com" Most modern dog tags are stamped from behind. Older dog tags were stamped from the face downward. mydogtag.com still has this option and it's what I used on my fully compliant and ATF registered ARK 1.0 machine gun. This may better comply with BATFE requirements. See the bits about stamping (impressing) below. If you use this technique, you can make it more legible by using some shoe polish, paint, etc. at the letters, and wipe off most of it, leaving the letters easily legible. These eggs are designed to be integrated into existing frames and receivers to be compliant with BATFE rules. State laws may vary. There are 2 eggs in this file. One is designed to be used with a dog tag printed on the top 2 lines and bottom 2 lines, and has a bar across the middle (line 3) to make it even harder to remove. The other assumes you put your longest lines at the top, and lower lines as you go down. There is a platform with corners sticking out of the egg... that is there to bury into your model. If you can bury that, you have 5mm of material behind the dogtag and >5mm in front and to the sides. To test this, try printing one egg by itself and slipping a dog tag into the print at a predetermined pause. You can determine the pause layer using your slicer. It's EZ on Bambu Labs Slicer. Not too bad on Cura if you're using an Ender. You may have no option but to watch it and pause manually, depending on your printer. The shape of the "Egg" matters! It is purposely designed to make it difficult to get a good grip with pliars, or get your screwdriver or knife behind the plate. The egg guarantees a minimum of 5mm of PLA+/Nylon etc. material around your dog tag. The goal isn't to make it impossible, but rather to make it at least as hard to obliterate, alter, or remove as other "conventionally manufactured" firearms already on the market (i.e. Glock).

.stl, .obj, and .glb files in the .zip

BATFE rules follows:

Firearms. You, as a licensed manufacturer, or importer of firearms, must legibly identify each firearm manufactured or imported as follows: 1. By engraving, casting, stamping (impressing) or otherwise conspicuously placing or causing to be engraved, cast, stamped (impressed) or placed on the frame or receiver thereof an individual serial number. The serial number must be placed in a manner not susceptible of being readily obliterated, altered, or removed, and must not duplicate any serial number placed by you on any other firearm. For firearms manufactured or imported on and after January 30, 2002, the engraving, casting, or stamping (impressing) of the serial number must be to a minimum depth of .003 inch and in a print size no smaller than 1/16 inch; and 2. By engraving, stamping (impressing), or otherwise conspicuously placing or causing to be engraved, cast, stamped (impressed) or placed on the frame, receiver, or barrel thereof of certain additional information. This information must be placed in a manner not susceptible of being readily obliterated, altered, or removed. For firearms manufactured or imported on and after January 30, 2002, the engraving, casting or stamping (impressing) of this information must be to a minimum depth of .003 inch. The additional information includes: 1 The model, if such designation has been made. 2. The caliber or gauge: 3. Your name (or recognized abbreviation) and also, when applicable, the name of the foreign manufacturer; 4. In the case of domestically made firearm, the city and State (or recognized abbreviation thereof) where you as the manufacturer maintain your place of business, and... (you get the idea)