does anyone have a 3d printer???

[cofi]

stole this thread from barf.com





http://www.ar15.com/forums/t_3_118/5...it_works_.html

Back in the discussion of 3D printing an AR lower, AmericanLoki requested that I start a new thread once it came time to actually test my printed lower. Well, I finally got around to the testing phase over the past few weeks.

To recap, I have an old Stratasys 3D printer (mid-to-late 90s machine, but works fine) and early last summer I printed a modified version of the lower from cncguns.com (I beefed up the front takedown lugs, bolt hold lugs, and added an integral trigger guard):


(the white one was a 75% scale version of the unmodified lower done as a feasibility test)

I assembled it first into a .22 pistol:


It's had over 200 rounds of .22 through it so far and runs great! To the best of my knowledge, this is the world's first 3D printed firearm to actually be tested, but I have a hard time believing that it really is the first (if anyone can point me to earlier work, it would be much appreciated).

But you guys want more than rimfire, I'm sure. Last weekend I finally re-assembled a .223 upper and gave it a go:



No, it did not blow up into a bazillion tiny plastic shards and maim me for life - I am sorry to have disappointed those of you who foretold doom and gloom.



However, it is giving me feed and extraction issues. As these issues persisted when I switched over to a standard aluminum lower, my problems appear to be with the upper. I'll give it a good cleaning/oiling and try it with some brass cartridges instead. Nevertheless, yes - a 3D printed lower is entirely usable. My model could stand to have a little more material on the buffer tower, but I'm extremely pleased with how well it's working so far. Further details on the construction and intial .22 testing are on my blog:
http://haveblue.org/?p=1041
http://haveblue.org/?p=1321

Also, keep an eye on oryhara's work on printing AR lowers - I think he may soon become the leading authority on the matter: http://rommie.digitalcrowbar.net/wordpress/












what a cool project!

[Circuits]

I've got one and am building another.

Those results are very neat, indeed - but remember that printable polymers have relatively low melting points, compared to the filled nylon or carbon fiber being used in commercial polymer firearms. If you make such a self-printed lower or upper, you can't let it get over 200C, which means no sustained or rapid firing, or it'll start to melt.

[DFBrews]

That is awesome! What kind of lol are you using? And what is the cost of the amount of polymer used?

NM read the arf article

[cofi]

I've got one and am building another.

Those results are very neat, indeed - but remember that printable polymers have relatively low melting points, compared to the filled nylon or carbon fiber being used in commercial polymer firearms. If you make such a self-printed lower or upper, you can't let it get over 200C, which means no sustained or rapid firing, or it'll start to melt.

How much did you end up spending on one????

[Circuits]

My first kit was $750, and came complete, plus I laid out more cash for some extra tools and such you need to put it together (extra heatshrink, standoffs, new soldering iron and/or tips, proper metric hex wrench stuff, if you don't already have everything).

It's possible to shop around and source parts in as cheap as $500-$600.

ABS filament is usually sold in kilo bundles, or even larger spools, at about $30-$50 per kilo, depending on quantity and shipping.

You'll also generally need a computer to hook up to it and drive the printing, and a boatload of 3d cad and modelling and control software for that computer - though most have freeware or shareware packages you can get started printing with for little or no money beyond having the computer itself.

If you just want to buy one, there are small ready-to-print machines under $1000, ranging to the low $2000s depending on their print volume.

[bogie]

Can you print with a wax instead of polymer with these printers? That would be useful since you could easily make an investment casting blank with the printed wax part, then cast a Magnesium or Aluminum part.

[cofi]

My first kit was $750, and came complete, plus I laid out more cash for some extra tools and such you need to put it together (extra heatshrink, standoffs, new soldering iron and/or tips, proper metric hex wrench stuff, if you don't already have everything).

It's possible to shop around and source parts in as cheap as $500-$600.

ABS filament is usually sold in kilo bundles, or even larger spools, at about $30-$50 per kilo, depending on quantity and shipping.

You'll also generally need a computer to hook up to it and drive the printing, and a boatload of 3d cad and modelling and control software for that computer - though most have freeware or shareware packages you can get started printing with for little or no money beyond having the computer itself.

If you just want to buy one, there are small ready-to-print machines under $1000, ranging to the low $2000s depending on their print volume.

thats wild im gonna have to start building one......do they sell stronger plastics for them or are you stuck with abs?

[Skullworks]

Can you print with a wax instead of polymer with these printers? That would be useful since you could easily make an investment casting blank with the printed wax part, then cast a Magnesium or Aluminum part.

Casting Magnesium - Now there is someone who wantes to live dangerously.

Yes it is done commerically - but thats a bit beyond the home hobbiest level.

[Circuits]

Can you print with a wax instead of polymer with these printers? That would be useful since you could easily make an investment casting blank with the printed wax part, then cast a Magnesium or Aluminum part.

You can directly do lost polymer - just burn away the plastic blank when firing the production mold.

[Circuits]

thats wild im gonna have to start building one......do they sell stronger plastics for them or are you stuck with abs?

There are different plastics you can use, but the two most common are ABS and PLA (bio plastic). The feed plastic just has to come in the right filament size, and have a melt temp within reach of the hotend/extruder (200-275C). Some plastics might need a vent hood or closed print cabinet, as they can off gas some nasty by products. My printer feeds 1.75mm diameter filament, and I only have ABS on hand at the moment.