3d Printer shenanigans

[WillBrink]

Ghost gun. So, he spent 1500 for a "untraceable" AR using a dedicated milling machine, made by the same group from this OP. I didn't even know there were dedicated milling machines to mill out 80% lowers. It just shows us with modern tech, gun control will only impact those who follow laws. No doubt, a push for a ban is in the works:

[Moose-Knuckle]

It just shows us with modern tech, gun control will only impact those who follow laws. No doubt, a push for a ban is in the works:

Just wait for these idiots to find out you can make a Sten from odds and ends picked up at your local Ace Hardware.

[Renegade]

Once 3d fabrications gets to the level of using materials much stronger than the plastics used now, perhaps some type of alloy specific to 3d printing, and it's game over.

We are already there. Daniel Defense has been 3D printing silencers for a while, and the Defense industry like Raytheon has been 3D printing Kinetic weapons for some time.

[WillBrink]

We are already there. Daniel Defense has been 3D printing silencers for a while, and the Defense industry like Raytheon has been 3D printing Kinetic weapons for some time.

I meant as non industrial scales. How does DD 3D print a silencer? Any vids? Does not sound cost effective compared to say CnC.

[turnburglar]

I meant as non industrial scales. How does DD 3D print a silencer? Any vids? Does not sound cost effective compared to say CnC.

The way (assuming) metal printing works is you have a box. As the print head passes over the box, one part is dropping the metal powder while the other part of the head is sintering the powder only in the areas that you want printed. as the print head starts at the bottom it builds the model layer by layer until your metal part is pulled from the box of powder. This process goes by many names but Direct Laser Sintering (DLS) or DLM are the two most common names. Because the printer fills the box with powder every single time a part is made, it makes sense to fill your build volume with as many parts as possible. Some of these machines could turn out probably 25-50 supressors each build. Also a huge benefit of 3D printing like this is that you can achieve shapes and designs that are impossible to make on a regular CNC. This would be critical for making a one peice supressor baffel.

Honestly I was surprised to see 3D printed surpressors on the market this quickly, but it doesnt surprise me that it happened.

As far as regular consumer grade 3D printers that typically print in ABS or PLA... these things are NOT up to spec to make functional gun parts. Even if you spec out some super tough polymer like PEEK or PEI (lol good luck printing it) the parts will always be far weaker at the layers than the materials are rated for. Engineers compensate for this by designing the stress on a part to go in a perpendicular direction as the print layers. This means that FDM printed parts are strong in only ONE direction. A typical firearm part sees stress from MANY directions, not only in the firing and cycling process, but also in typical rough handeling.

Now if I took one of those materials I mentioned earlier (Peek, PEI) and injection molded a lower, you would have a VERY useful part. I kinda snicker when I see all those broken polymer lowers. They where just using the wrong polymer.

[FromMyColdDeadHand]

There are ways around the layer issue. I've printed mounts (Spigot to swivel nubbin) for Sinclair tactical bipods and some barrier stops. Those that know me know that I can put massive amounts of pressure leaning into a bipod or stop. The key, I've found, is to use something to reinforce the layer adhesion axis. The layers lay down horizontally, so if I leave straight holes in the vertical as I print, I can then come back and put things like wood screws and glue in carbon fiber tubes to reinforce that weak layer issue.

Use 60% plus infill, three perimeters from a 0.4 nozzle, 0.3 layers and a 1.5 base and top.

I leave the screws a little long on the barrier stops towards the front so that the stop has a little 'bite' to it. Conical head screws can be flush.

Maybe a bit Frankenstien, but it has worked for me. You kind of have to plan the part. That can be an issue, especially if you are using a filament printer with out support and you have to worry about overhangs and such.

I'm traveling this week and don't have much with me. Next week I'll post pics the doo-dads that I've worked up so far.

[hotrodder636]

The technology is impressive. I just saw this week a “micro CNC” machine that will mill out 80% lowers, pistol or AR.

[Alex V]

The technology is impressive. I just saw this week a “micro CNC” machine that will mill out 80% lowers, pistol or AR.

Ghost Gunner 2. For $2,000 you too can have a machine mill your own 80% lowers. lol

[WillBrink]

The technology is impressive. I just saw this week a “micro CNC” machine that will mill out 80% lowers, pistol or AR.

My post above, #21, is what that's about.

[turnburglar]

There are ways around the layer issue. I've printed mounts (Spigot to swivel nubbin) for Sinclair tactical bipods and some barrier stops. Those that know me know that I can put massive amounts of pressure leaning into a bipod or stop. The key, I've found, is to use something to reinforce the layer adhesion axis. The layers lay down horizontally, so if I leave straight holes in the vertical as I print, I can then come back and put things like wood screws and glue in carbon fiber tubes to reinforce that weak layer issue.

Use 60% plus infill, three perimeters from a 0.4 nozzle, 0.3 layers and a 1.5 base and top.

I leave the screws a little long on the barrier stops towards the front so that the stop has a little 'bite' to it. Conical head screws can be flush.

Maybe a bit Frankenstien, but it has worked for me. You kind of have to plan the part. That can be an issue, especially if you are using a filament printer with out support and you have to worry about overhangs and such.

I'm traveling this week and don't have much with me. Next week I'll post pics the doo-dads that I've worked up so far.

Your infill and perimeter settings all sound good, but did you know that you could achieve better layer adhesion if you go with a bigger nozzel and layer path? Something like a 0.6 nozzel laying down 0.5 layers would be tougher layer adhesion for sure. As with 3D printing tuning is neccesary. The part looses some resolution but if you are already willing to do any post print proccessing its a useful trick to increase strength. Another thing you could do is make your part out of the right materials. TPU would probably work well for a bipod that needs loading.

I get what your saying about the wood screws reinforcing the layers. While that technique can work on certain models, Im sure the firearm parts that people want to print like uppers and lowers would be near impossible to do in a similar fashion. 3D printing is excellent for making a physcial version of a CAD file and learning what changes need to be made for the next iteration. Unfortunetly 3D printing cant quite produce functional hard use end user products yet. Atleast not on the desktop sub 3K price range. I am aware of the markforged printers and their fused filament process. While cool it still cant do the complex shapes that 3D printers are famous for, and their patent locked down that technology pretty solidly. So dont expect anyone but them to support it.