new AR15 files


Source Files

Lower part 1

Lower part 2

This entry was posted in Guns, Printing and tagged , . Bookmark the permalink.

29 Responses to new AR15 files

  1. Arman says:

    What are the rescale settings in mm? I load and slice your files with slic3r and when done printing they are too small. Not the right size needs to be scaled up somehow. Can you provide the rescale settings? Or do you have the files that are complete and ready to print?

    • turomar says:

      the files from cncguns came in inches. 1 inch = 25.4mm. I exported the stl files as mm, so those are good to print. If your slicing software read them as inches then you need to fix it. But if a magazine only just barely doesn’t fit in the magazine well, then slic3r is doing interior cavities 1 filament-width too small, as i’ve seen it do for me many times. I believe this is a bug in slic3r. I used a file to grind the inside of the magazine well out such that a magazine would fall freely when released. I also altered the model to be .1mm wider around the perimeter of the magazine well. This decreased the amount of filing need.
      So how small are the printed objects? If you’ve got a factor of about 25, then you’re reading inches, but if it’s within like 10%, you need to file it down.
      FYI, when I run my AR15 slt files through slic3r, I use 100% infill with 1 perimeter. I find that works best for me.

  2. Arman says:

    When you say infill. Do you mean fill density in the print settings? I have it set at 1.0. What should I set it at? I am also trying to print out the DefCad V5 Lower. Having problems with the sic3r settings. I use Slic3r V 0.7.1.

    • turomar says:

      1.0 fill density is 100% infill.
      Also, never use any version of slic3r but the latest one. 0.7.1 is positively ancient. That was barely out of beta. no wonder you are having problems.

      I can’t speak to any lower design but my own. The only one I’ve tried to print is the model from cncguns which is what I based all of my modifications on.

      • Arman says:

        Your a genius Man! Have Rostock Max printing your lower as I type. That 1.0 fill density is working like a charm! If only DefCad would add a beard to their AR15 STL file, like you did, it would be easier to print. I tried printing it but it keeps warping. Here is my email address elqisqeyano @ aol . com, I’d like to thank you personally via private email. Keep up the good work. Email me with any future good 3D printable stl files.


  3. Arman says:

    I updated Slic3r to 0.9.9 V and it works like a charm. I use Repetier-Host to slice with Slicer V 0.9.9 then I load it onto Pronterface to print with your mentioned settings. Like a charm! Thanks!

  4. Arman says:

    What Layer height are you using? I’m trying it at 0.08. Is 0.05 better?

  5. Arman says:

    6 hours into the print and the hot end tip was coming up towards the front and the rear was level with the print. I don’t know if it’s file error or printer error?

    • turomar says:

      really couldn’t tell you what is wrong, having no idea how your printer was calibrated or assembled, and not being there to see it myself.

      It printed fine for me on my printer. I put 120 rounds downrange once assembled. Could have shot more but it was february and freezing out.

      • Arman says:

        Sweet. I figured it out. I hit the surge protectors on and off switch by mistake and it shut off and on the machine. Bummer. 2nd try and hope, with all the info you provided, that it’s successful.

        You in the states?

      • Arman says:

        How long do you think these lowers can survive? How many round you figure they can shoot? Also, are you treating the finished product with anything? Like acetone or something?

  6. Arman says:

    How close should I keep the Hot end nozzle to the bed to print at 0.25?

    • turomar says:

      close enough so that the base layer sticks and stays stuck throughout the print. I don’t measure my Z home distance. I check the first layer for the proper quantity of smooshed-into-the-PET-tape. I can turn the Z screws by hand if the print has started and i don’t like the Z starting distance.
      Too little smoosh and Z goes down. Too much and Z moves up. With the AR15 lower I prefer more smoosh to less smoosh because it is so inclined to warp.

      If you’re getting warp off the bed try wiping with acetone or increasing brim in slic3r. Or you could sand the tape and use ABS goo. acetone and a nice smoosh are all I need to print with the existing modeled brim. Also PET Tape sticks to ABS better than Kapton. I don’t use kapton at all anymore.

  7. Arman says:

    I’m keeping the bed temp at 110 for ABS. It’s sticking better at that temp range.

  8. Arman says:

    I have to state this again! Your a genius Turoma! It appears to be printing flawlessly now. Let’s just hope I can keep from bumping the surge protector again. LOL

    Thanks Again.


  9. Arman says:

    Flawlessly printed in 5 hours and 37 minutes. Wish I could send you pics.

  10. Arman says:

    Did you ever try it with .223 5.56 ammo?

    • turomar says:

      Kind of.
      5.45×39 russian is an order of magnitude less expensive than .223, and has more muzzle energy.
      Smith and wesson makes an AR15 upper in that caliber, and I found one used.
      I put 120 rounds downrange with that upper on my printed lower and no ill effects were observed. It was below freezing out, and didn’t feel like wasting a full can(1080 rounds) of ammo just to prove that my rifle can handle it, but I believe that it can handle as many rounds as I feel like shooting.

      • Arman says:

        I’m starting to believe the same. Great print. Everything is perfectly aligned after print. Not much clean up left. Took 5 hours 37 minutes. Have you seen those ARAK 21 uppers? They don’t require buffer tower. Would be nice to have an STL file of a lower specifically designed for those uppers that don’t require buffer towers. They’d end up looking like Heckler and Koch. Leave buffer tower out and replace it with just the rear take down access hole.

  11. chris says:

    I have been trying to print your lower but when I use kiss slicer there is an error on the bolt catch pin boss. The one closet to the back. Seems like the the boss wasn’t merged when it was extruded in solid works even though it looks fine. Nettfab didn’t fix the stl file. Anyway you would send me the sldprt file. Any version up 2012 will work. I want to see if I can fix it. Netfabb shows it as a separate part from the main body.

    • turomar says:

      #1 Neither I nor any other users have had an issue trying to skein this with Slic3r.
      #2 the design file is uploaded.
      #3 I have already fixed the problem and uploaded a new STL

      • grill says:

        Any chance you could upload the sldprt files for the buffer tower and stock. I printed and test fired with the files you had uploaded but I would like to modify where the 5/16th rod is positioned as well as how the buffer tower mates to the rest of the lower. If you would like, I can send you a file with all the changes.

  12. Arman says:

    Have you tried Nylon 618 for printing these lowers? A bit tricky to work with but very strong. When printing, the trick is to not use 100% infill. ^18 is tough enough that it does not require to be printed at 100% infill. I am trying it at 10% right now. Layer height is also a factor using 618, I find 0.40 or above to work better that .40 and lower in the .25 to .10, squeezes the filament down too much and distorts the dimensions. So right now I am trying it at .40 see how that goes, might bring it up to .50.

  13. Arman says:

    Taulman has also come out with Nylon 645, it’s just like ABS, prints just like it, same temp and settings, but it’s a lot tougher than ABS, not as brittle. I have some that I bought being shipped to me. They are giving out a free 1 lb roll of the stuff at I am positively sure, if you show them what you have accomplished so far, that they will send you some for free. Look them up. These guys are going to help us revolutionize the Poly 3D printing industry with their efforts.

  14. Lars says:

    How does one who knows nothing about 3d printing find a suitable printer to create such wonderful works of art as described on the forum? None of my friends know anything about 3d printing, including my techiest geekiest friends. Research has showed me some machines, but not where they are available for use. How is it possible to obtain one to do such work?

Leave a Reply

Your email address will not be published. Required fields are marked *