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Posted: 9/21/2011 3:42:57 AM EST
In question to the Print your own Lower Thread

The questions of legalities comes up for me

My son has access to Very High End 3d Printers, so I f I have Him print it up (manufacture)
for me, He will be the one making it and then he would be transferring it to me.

I have a CNC milling machine so I can engrave a Serial Number
into the lower prior to him transferring it to me.

Can anyone point me to the the the laws governing this.

Thank you
Link Posted: 9/21/2011 3:45:59 AM EST
[Last Edit: 9/21/2011 3:50:36 AM EST by tc2k11]
Tell your son to hide his dogs...

ETA: He'd be manufacturing without a license. The serial number! It means nothing! He could make one for himself, no problem, but if he intends to transfer it... Hide the dogs...

Posted Via AR15.Com Mobile
Link Posted: 9/21/2011 3:49:41 AM EST
He can only make one for himself, not with the intent to give it to someone else.
Link Posted: 9/21/2011 3:51:36 AM EST
Originally Posted By makintrax73:
He can only make one for himself, not with the intent to give it to someone else.


This is what I've understood it to be. I can't find documentation though.
Link Posted: 9/21/2011 3:58:49 AM EST
Originally Posted By makintrax73:
He can only make one for himself, not with the intent to give it to someone else.


Actually, he can gift it, and he can sell it, but he can't "be in the business". What constitutes being "in business" is a big gray area. Once in a while because you didn't want it anymore, or want to free up money for a new project is fine and legal, state laws notwithstanding. Twenty a year is probably a sure fire trip to club Fed. In between that? Who knows. Purely up to the discretion of the ATF.

3d printers are somewhat legally uncharted territory, however, IANAL and all standard disclaimers apply, I'd say if you were there with your son, working with him to load the design, you make a few clicks on the PC, and there while the lower was printed, take it out of the vat when it's done etc..., the case can be made that "you" manufactured it.

Being present for other steps in arms manufacture, like being present when having NFA stuff engraved when you are the builder/manufacturer of record, when the engraver isn't a FFL etc. is legally sufficient. So the standards should be the same, or less for Title 1 arms.
Link Posted: 9/21/2011 4:00:08 AM EST
I dont think id want to be a guinnea pig for this lol
Link Posted: 9/21/2011 4:01:26 AM EST
It would be an interesting item, but I sure do not want to cross any lines on this.

Having it made up as a 80% (or whatever is legal) would be a bit
against the whole reason of it being "3d Printed" in the first place.

So short of me buying or leasing a machine, it looks like I'm out of luck.
Link Posted: 9/21/2011 4:03:36 AM EST
[Last Edit: 9/21/2011 5:01:02 AM EST by AmericanLoki]
It should be the same as doing an 80% lower. Just make sure that you are there, and no money changes hands.

Also, if you are serious, I would advise doing some testing before shooting the rifle yourself. As in, pull the trigger with a string from behind a barrier.
Link Posted: 9/21/2011 4:07:07 AM EST
Originally Posted By AJ_Dual:
Originally Posted By makintrax73:
He can only make one for himself, not with the intent to give it to someone else.


Actually, he can gift it, and he can sell it, but he can't "be in the business". What constitutes being "in business" is a big gray area. Once in a while because you didn't want it anymore, or want to free up money for a new project is fine and legal, state laws notwithstanding. Twenty a year is probably a sure fire trip to club Fed. In between that? Who knows. Purely up to the discretion of the ATF.

3d printers are somewhat legally uncharted territory, however, IANAL and all standard disclaimers apply, I'd say if you were there with your son, working with him to load the design, you make a few clicks on the PC, and there while the lower was printed, take it out of the vat when it's done etc..., the case can be made that "you" manufactured it.

Being present for other steps in arms manufacture, like being present when having NFA stuff engraved when you are the builder/manufacturer of record, when the engraver isn't a FFL etc. is legally sufficient. So the standards should be the same, or less for Title 1 arms.


Interesting, This may actually be worth further looking into.

He also is a "Gun Guy"

I did show him the 3d rendering of it last night on my cad program
and I was thinking that the pivot points may be a weak area.

He looked at it and thought they look strong enough and he informed
me how it should be orientated for better strength between the layers.


Link Posted: 9/21/2011 4:09:39 AM EST
IIRC, if you push the start button, you are the maker

i wonder what joys could be had in a 3d printed 80 percent?

the mag well could be open but sealed top & bottom

the pin holes could be marked
Link Posted: 9/21/2011 4:16:05 AM EST
A lot of this would depend on his company as well.

So we may need to take his boss out to the range a few times

Link Posted: 9/21/2011 4:18:54 AM EST
How durable is the polymer?
Link Posted: 9/21/2011 4:22:58 AM EST

Originally Posted By macman37:
How durable is the polymer?

This.


Though, I've heard that guys have made lowers out of wood before.....
Link Posted: 9/21/2011 4:25:44 AM EST
[Last Edit: 9/21/2011 4:30:12 AM EST by BatchelorGroda]
Originally Posted By Mr_Harry:
In question to the Print your own Lower Thread

The questions of legalities comes up for me

My son has access to Very High End 3d Printers, so I f I have Him print it up (manufacture)
for me, He will be the one making it and then he would be transferring it to me.

I have a CNC milling machine so I can engrave a Serial Number
into the lower prior to him transferring it to me.

Can anyone point me to the the the laws governing this.

Thank you


A 3D printer will make the shape, but a 3D-printed lower would NOT have the strength needed to make it work more than once.

You would have better luck with a Hesse/Vulcan/Blackthorn plastic lower.

As far as legalities...you're in New York, so all bets are off.

As far as maybe if you were in another state...your son might be an unlicensed dealer/manufacturer if he made it for you.

Originally Posted By macman37:
How durable is the polymer?


It is not durable.

Most 3D printers use a composition of corn starch, which is basically glued together with a binder...at best it would mimic a non-reinforced fiberglass.

You would get better strength out of gluing pieces of paper together with Elmers glue.


Link Posted: 9/21/2011 4:28:57 AM EST
There really is a whole lot of load on the lower. The pivots maybe but couldn't you just drill and bush them?
Link Posted: 9/21/2011 4:29:41 AM EST
Originally Posted By macman37:
How durable is the polymer?


They have some high temp stuff that is very strong.

The quality of the parts that come out of the
machines he works on are absolutely amazing.

You would never know they were printed.

Link Posted: 9/21/2011 4:31:36 AM EST
[Last Edit: 9/21/2011 4:32:14 AM EST by AmericanLoki]
Originally Posted By macman37:
How durable is the polymer?


Most of the hobby printers use ABS:
http://en.wikipedia.org/wiki/Acrylonitrile_butadiene_styrene
The most important mechanical properties of ABS are impact resistance and toughness. A variety of modifications can be made to improve impact resistance, toughness, and heat resistance.


I can't speak to industrial printers, and someone who knows more than me about this will probably be along shortly anyways.
Link Posted: 9/21/2011 4:35:01 AM EST
[Last Edit: 9/21/2011 4:35:48 AM EST by BatchelorGroda]
Originally Posted By captainpooby:
There really is a whole lot of load on the lower. The pivots maybe but couldn't you just drill and bush them?


Your bushings would work their way out - loosen-up.

People, 3D printing as we know it is a very cool technology for making PROTOTYPES in most cases. Prototypes that usually need to be cast in metal and/or forged and then machined into working items.

Some people use the machines to make little action figures, or DECORATIVE items, and then paint them...done...no strength is needed, so the printed part is done after it comes out of the printer...minus some smoothing and detailing in some cases.

If you ever want to consider using a (current) 3D printer set-up for something that SHOULD be made of metal, consider it a "one use" item.

Link Posted: 9/21/2011 4:36:29 AM EST
3D printers are going to create a whole bunch of ulcers for people who think the answer to everything is more regulation. They have the potential to up-end the very foundation of our legal system with regards to creative rights and use, possession, commerce, and the control of restricted or prohibited items.

Which I think is fucking awesome... we just need to fend off the bureaucrats long enough to make it clear to them that their jobs are over and they are no longer wanted.
Link Posted: 9/21/2011 4:38:41 AM EST
[Last Edit: 9/21/2011 4:40:21 AM EST by PFC_Kramer]
3d printing from plastics even with the best materials won't give you a part that has the same strength and quality of a injection molded part. Just something to think about. If you have the intention of using this part as is and building a rifle out of it, it'll fail soon. You'll have to have your son reinforce and build up the design quite a bit if you intend to turn this into a functioning receiver.

I use 3d printers day in and day out for work. They are GREAT tools for mocking up assemblies and testing fits and occasionally they work well for one off parts. But 99% of the time the part is very weak and delicate (our machines use ABS plastic). Some machines have the abilities to lay some really tough plastics. Just a few things to think about.
Link Posted: 9/21/2011 4:41:05 AM EST

Originally Posted By Mr_Harry:
It would be an interesting item, but I sure do not want to cross any lines on this.

Having it made up as a 80% (or whatever is legal) would be a bit
against the whole reason of it being "3d Printed" in the first place.

So short of me buying or leasing a machine, it looks like I'm out of luck.

Just have him install the program and you set up and run the machine.


Load some media, push the buttons, you made it yourself.

.
Link Posted: 9/21/2011 4:43:20 AM EST
question...how is this considered 'printing'?
Link Posted: 9/21/2011 4:43:22 AM EST
Originally Posted By Mr_Harry:
It would be an interesting item, but I sure do not want to cross any lines on this.

Having it made up as a 80% (or whatever is legal) would be a bit
against the whole reason of it being "3d Printed" in the first place.

So short of me buying or leasing a machine, it looks like I'm out of luck.


Lease the machine for 1 dollar. Then hire your son as an employee(remember minimum wage laws) and he can make your lower for you.
Link Posted: 9/21/2011 4:44:58 AM EST
Originally Posted By makintrax73:
He can only make one for himself, not with the intent to give it to someone else.


Link Posted: 9/21/2011 4:44:58 AM EST
It would probably make a good casting mould though. Oh well, I'm no engineer, I have no idea how to do something like this.
Link Posted: 9/21/2011 4:47:09 AM EST
I doubt it will last long but I'd really like to see it.
Link Posted: 9/21/2011 4:47:31 AM EST
Originally Posted By Mr_Harry:
In question to the Print your own Lower Thread

The questions of legalities comes up for me

My son has access to Very High End 3d Printers, so I f I have Him print it up (manufacture)
for me, He will be the one making it and then he would be transferring it to me.

I have a CNC milling machine so I can engrave a Serial Number
into the lower prior to him transferring it to me.

Can anyone point me to the the the laws governing this.

Thank you


Even if you could print [SLA, SLS] a lower it would not be worthwhile. If you have access to DMLS, then you could make an interesting yet heavy lower. For the risk you would be taking it’s a really bad idea.
Link Posted: 9/21/2011 4:47:33 AM EST
Well it may be some time until I get the chance to
do this, My biggest concern is the legalities of it.
Link Posted: 9/21/2011 4:48:12 AM EST

Originally Posted By Mr_Harry:
In question to the Print your own Lower Thread

The questions of legalities comes up for me

My son has access to Very High End 3d Printers, so I f I have Him print it up (manufacture)
for me, He will be the one making it and then he would be transferring it to me.

I have a CNC milling machine so I can engrave a Serial Number
into the lower prior to him transferring it to me.

Can anyone point me to the the the laws governing this.

Thank you

Go to his shop, when it's time to make it, you hit the CTRL-P, ENTER.

You made it, perfectly legal.


Link Posted: 9/21/2011 4:48:47 AM EST
Buy yourself a makerbot for $1000
Print as many as you want
Link Posted: 9/21/2011 4:51:35 AM EST
Originally Posted By macman37:
It would probably make a good casting mould though. Oh well, I'm no engineer, I have no idea how to do something like this.


I am an engineer. This is an option if you have a unique concept you wanted to cast. Rapid prototypes are frequently used as patterns for casting parts in urethane.
Link Posted: 9/21/2011 4:54:05 AM EST
Show me where he would be disallowed from making one and giving it to his dad…

Show me where he would be disallowed from making one and selling it to me. (As long as he doesn’t make a habit of it as in "manufacturing weapons as a course of business without a license”)_

<o:p> </o:p>

If I milled an 80% lower, or built a gun from scratch and decided to give it to my dad or sell it, there is nothing illegal about it.




As long as it's a Title-1 weapon it is a non-issue.

Link Posted: 9/21/2011 4:56:01 AM EST
Interesting. tag.
Link Posted: 9/21/2011 4:58:39 AM EST
Originally Posted By BatchelorGroda:
[snip]

Originally Posted By macman37:
How durable is the polymer?


It is not durable.

Most 3D printers use a composition of corn starch, which is basically glued together with a binder...at best it would mimic a non-reinforced fiberglass.

You would get better strength out of gluing pieces of paper together with Elmers glue.




Most people involved in real prototyping do not use these corn starch printers. We use SLA, SLS, DMLS, or cast urethane. You are correct about the Z Corp printing technology, but there are much better options available today
Link Posted: 9/21/2011 5:06:26 AM EST

Originally Posted By 245PDG:
Originally Posted By BatchelorGroda:
[snip]

Originally Posted By macman37:
How durable is the polymer?


It is not durable.

Most 3D printers use a composition of corn starch, which is basically glued together with a binder...at best it would mimic a non-reinforced fiberglass.

You would get better strength out of gluing pieces of paper together with Elmers glue.




Most people involved in real prototyping do not use these corn starch printers. We use SLA, SLS, DMLS, or cast urethane. You are correct about the Z Corp printing technology, but there are much better options available today

While the SLA (3D printer) resins are getting better, such as Somos NeXt, I sure as hell wouldn't shoot a gun with an SLA lower!
Link Posted: 9/23/2011 7:00:04 AM EST
I printed this lower on my Stratasys a few months ago (the white one is a 75% scale version that I ran first as a feasibility test).

http://haveblue.org/ar15lowertests.jpg

The material is ABS plastic, and is quite stout. Nevertheless, I beefed up the front lugs and bolt catch lugs and added an integral trigger guard for more strength. I'm currently fitting parts to it but need to ream the holes a little. I see no reason why it won't work - after all, orions_hammer has made lowers out of wood and HDPE: http://www.orions-hammer.com/

Even so, I'll be testing it first with a CMMG .22 kit.
Link Posted: 9/23/2011 7:19:04 AM EST
Originally Posted By HaveBlue:
I printed this lower on my Stratasys a few months ago (the white one is a 75% scale version that I ran first as a feasibility test).

http://haveblue.org/ar15lowertests.jpg

The material is ABS plastic, and is quite stout. Nevertheless, I beefed up the front lugs and bolt catch lugs and added an integral trigger guard for more strength. I'm currently fitting parts to it but need to ream the holes a little. I see no reason why it won't work - after all, orions_hammer has made lowers out of wood and HDPE: http://www.orions-hammer.com/

Even so, I'll be testing it first with a CMMG .22 kit.


Awesome.


Link Posted: 9/23/2011 7:22:30 AM EST
Originally Posted By HaveBlue:
I printed this lower on my Stratasys a few months ago (the white one is a 75% scale version that I ran first as a feasibility test).

http://haveblue.org/ar15lowertests.jpg

The material is ABS plastic, and is quite stout. Nevertheless, I beefed up the front lugs and bolt catch lugs and added an integral trigger guard for more strength. I'm currently fitting parts to it but need to ream the holes a little. I see no reason why it won't work - after all, orions_hammer has made lowers out of wood and HDPE: http://www.orions-hammer.com/

Even so, I'll be testing it first with a CMMG .22 kit.


Sweet.

Thank you
Link Posted: 9/23/2011 7:26:26 AM EST

Originally Posted By swingset:

Originally Posted By Mr_Harry:
In question to the Print your own Lower Thread

The questions of legalities comes up for me

My son has access to Very High End 3d Printers, so I f I have Him print it up (manufacture)
for me, He will be the one making it and then he would be transferring it to me.

I have a CNC milling machine so I can engrave a Serial Number
into the lower prior to him transferring it to me.

Can anyone point me to the the the laws governing this.

Thank you

Go to his shop, when it's time to make it, you hit the CTRL-P, ENTER.

You made it, perfectly legal.




That's what I came here to post .


And forgive my stupidity on this issue , but why couldnt you just slow the feeds and the depth of cut in the program , and use a chunk of 6061 ?

Link Posted: 9/23/2011 7:28:40 AM EST

Originally Posted By HaveBlue:
I printed this lower on my Stratasys a few months ago (the white one is a 75% scale version that I ran first as a feasibility test).

http://haveblue.org/ar15lowertests.jpg

The material is ABS plastic, and is quite stout. Nevertheless, I beefed up the front lugs and bolt catch lugs and added an integral trigger guard for more strength. I'm currently fitting parts to it but need to ream the holes a little. I see no reason why it won't work - after all, orions_hammer has made lowers out of wood and HDPE: http://www.orions-hammer.com/

Even so, I'll be testing it first with a CMMG .22 kit.


Beautiful work , that 3/4 scale piece is cute as hell .

Link Posted: 9/23/2011 7:32:38 AM EST
Originally Posted By CONKLE73:
Show me where he would be disallowed from making one andgiving it to his dad…

Show me where he would be disallowed from making one andselling it to me. (As long as he doesn’t make a habit of it as in "manufacturingweapons as a course of business without a license”)_

<o:p> </o:p>

If I milled an 80% lower, or built a gun from scratch anddecided to give it to my dad or sell it, there is nothing illegal about it.




As long as it's a Title-1 weapon it is a non-issue.


You might want to check the BATFE website for the letter on making a firearm..
A non-licensee cannot make a firearm with the intent to transfer (sell, give, barter, etc.) it.
A non-licensee can make a firearm for his/her own use.
A non-licensee can transfer a firearm which was made for his/her own use. BATFE states the the maker "should" mark the receiver with his name and the city where the firearm was made before transferring it.
The hypothetical is that the lower receiver would be made WITH the intent to transfer it.
Link Posted: 9/23/2011 7:36:25 AM EST
[Last Edit: 9/23/2011 7:46:11 AM EST by Meche_03]
I do not doubt that a rapid prototype / direct manufactured / additive manufactured lower will work. It is a question on how long it will function before failure and how will it fail.



If your going to make one for fun then yes it will work. But with the tools available why not change the solid model abit to make it more durable.

RED - increase the OD of the buffer tube area, possibly make threads so they are undersized so a tap actually cuts the profiles. Or make them the thread pitch to heli-coil, all be it a special order part.
Green - thread brass bushings into holes, there are bushings made to do this in plastics. Especially the trigger and hammer pins since they wear with aluminum lowers.
Orange - Increase thickness of these areas to increase strength. Make it more like a slab or some billet lowers out there. The profile of the AR lower was driven by the need to decrease mass while keeping a set useful life expectancy

edit, i would request a scale barreled upper for it. + a stand to hold it up through the mag port, make a desk model .....for work of course to show the machines capabilities.
Link Posted: 9/23/2011 7:39:40 AM EST
It's not going to have the strength of carbon fiber or a polymer like Zytel in its construction. It will be useless.
Link Posted: 9/23/2011 7:54:03 AM EST
Originally Posted By ultramagbrion:

Originally Posted By swingset:

Originally Posted By Mr_Harry:
In question to the Print your own Lower Thread

The questions of legalities comes up for me

My son has access to Very High End 3d Printers, so I f I have Him print it up (manufacture)
for me, He will be the one making it and then he would be transferring it to me.

I have a CNC milling machine so I can engrave a Serial Number
into the lower prior to him transferring it to me.

Can anyone point me to the the the laws governing this.

Thank you

Go to his shop, when it's time to make it, you hit the CTRL-P, ENTER.

You made it, perfectly legal.




That's what I came here to post .


And forgive my stupidity on this issue , but why couldnt you just slow the feeds and the depth of cut in the program , and use a chunk of 6061 ?





I would want it out of plastic primarily because it can be done.

If I just wanted a stripped lower I'd just buy one

Link Posted: 9/23/2011 9:42:50 AM EST
Have him install the gotomypc program and hit the start button yourself.
Link Posted: 9/23/2011 12:07:35 PM EST
Originally Posted By Meche_03:
I do not doubt that a rapid prototype / direct manufactured / additive manufactured lower will work. It is a question on how long it will function before failure and how will it fail.

If your going to make one for fun then yes it will work. But with the tools available why not change the solid model abit to make it more durable.

RED - increase the OD of the buffer tube area, possibly make threads so they are undersized so a tap actually cuts the profiles. Or make them the thread pitch to heli-coil, all be it a special order part.
Green - thread brass bushings into holes, there are bushings made to do this in plastics. Especially the trigger and hammer pins since they wear with aluminum lowers.
Orange - Increase thickness of these areas to increase strength. Make it more like a slab or some billet lowers out there. The profile of the AR lower was driven by the need to decrease mass while keeping a set useful life expectancy

edit, i would request a scale barreled upper for it. + a stand to hold it up through the mag port, make a desk model .....for work of course to show the machines capabilities.


Thanks for the tips! Yes, brass bushings were most certainly my thoughts for the holes, but then I started pondering having pockets in the model into which drilled steel plates could be inserted partway through the build (then let the printing complete, sealing the plates inside). This is indeed just for fun, so I'll be running it as-is to start with. If I really wanted to start beefing it up, I'd begin by experimenting with a polycarbonate/ABS blend for the build material, then reinforcing areas like you point out.

As for a scale barreled upper, I'd actually like to do that for the 75% lower, as the little guy is really cute and deserves to be kitted out with scale parts...
Link Posted: 9/23/2011 12:08:04 PM EST
Who is ever going to know who made it unless you tell them?

Practically speaking tho, why bother making one anyways?

I had an idea for using my CNC machine to make foam lower halves and then do slip casting out of aluminum. I think it would work. But the price on lowers is so ridiculously low now, why bother?
Link Posted: 9/23/2011 12:13:42 PM EST
[Last Edit: 9/23/2011 12:14:02 PM EST by LuckyDucky]
Originally Posted By HaveBlue:
Originally Posted By Meche_03:
I do not doubt that a rapid prototype / direct manufactured / additive manufactured lower will work. It is a question on how long it will function before failure and how will it fail.

If your going to make one for fun then yes it will work. But with the tools available why not change the solid model abit to make it more durable.

RED - increase the OD of the buffer tube area, possibly make threads so they are undersized so a tap actually cuts the profiles. Or make them the thread pitch to heli-coil, all be it a special order part.
Green - thread brass bushings into holes, there are bushings made to do this in plastics. Especially the trigger and hammer pins since they wear with aluminum lowers.
Orange - Increase thickness of these areas to increase strength. Make it more like a slab or some billet lowers out there. The profile of the AR lower was driven by the need to decrease mass while keeping a set useful life expectancy

edit, i would request a scale barreled upper for it. + a stand to hold it up through the mag port, make a desk model .....for work of course to show the machines capabilities.


Thanks for the tips! Yes, brass bushings were most certainly my thoughts for the holes, but then I started pondering having pockets in the model into which drilled steel plates could be inserted partway through the build (then let the printing complete, sealing the plates inside). This is indeed just for fun, so I'll be running it as-is to start with. If I really wanted to start beefing it up, I'd begin by experimenting with a polycarbonate/ABS blend for the build material, then reinforcing areas like you point out.

As for a scale barreled upper, I'd actually like to do that for the 75% lower, as the little guy is really cute and deserves to be kitted out with scale parts...


Is it feasible to do this in the entire piece with wire or strips of metal much like rebar is placed into concrete to provide strength?
Link Posted: 9/23/2011 12:20:23 PM EST
Originally Posted By 1Andy2:
Who is ever going to know who made it unless you tell them?

My Conscious (I don't want to lie about it when asked)


Practically speaking tho, why bother making one anyways?

Because it can be done and it would be interesting to do


I had an idea for using my CNC machine to make foam lower halves and then do slip casting out of aluminum. I think it would work. But the price on lowers is so ridiculously low now, why bother?

Because it would be interesting to do (yep I'm a nerd)



Link Posted: 9/23/2011 12:24:47 PM EST
make it an 80% lower
Link Posted: 9/23/2011 12:26:30 PM EST

Originally Posted By HaveBlue:
I printed this lower on my Stratasys a few months ago (the white one is a 75% scale version that I ran first as a feasibility test).

http://haveblue.org/ar15lowertests.jpg

The material is ABS plastic, and is quite stout. Nevertheless, I beefed up the front lugs and bolt catch lugs and added an integral trigger guard for more strength. I'm currently fitting parts to it but need to ream the holes a little. I see no reason why it won't work - after all, orions_hammer has made lowers out of wood and HDPE: http://www.orions-hammer.com/

Even so, I'll be testing it first with a CMMG .22 kit.
why not sleeve the take down pin holes?

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