So I didn't know where else to post this question. But as it required a knowledge of the technical aspects of 3D printing, and economics. I figured here would be the best bet.

As I understand many manufacturers are switching over to 3D printing. Aerospace I hear really loves it due to the reduction in wasted material and the costs associated thereof.

Companies like MarkForged and their competitors are coming out with new metal 3d printers over the course of the next couple years. Do you think we will begin to see firearm manufacturers using them in production of firearm parts as printer costs fall?

It just seems like the natural progression of things as I feel quality control would be more consistent, complex geometries achievable, material waste reduction, etc... Beyond costs, are there any issues that would hinder the switch from conventional machining in regards to the material being used in printing processes?

Interested to hear your guys thoughts on this.

It probably won't be cost effect for gun companies for a long time.

Its  all related to cost.  The materials cost for aerospace is sky high, you like that, so the high printer cost and slow output can be overcome.  Plus some of the aerospace materials are crazy to machine and have huge consumable costs and long machining times that helps the sintering machines be productive alternatives.  It would be neat to see but normal cnc can be very cost efficient with the proper parts.

From what I've seen the process will have to speed up dramatically to even reach parity with CNC on a cost per unit (really time per unit) basis.  A lot of parts can be made in a step process where you rough out X amount of parts from one long piece of metal then they are detached from each other at the end of the process.  That is something outside of how 3D printing typically works.  If parts can be made durable enough it could bring down the cost of one-off and very low volume parts, to the point some things could be customized by the end user on ordering.

Remember that time, especially man hours, is usually the biggest cost in any product.

Aerospace loves it because you can make parts that would be otherwise impossible to machine.  i.e. a solid turbine blade with a honeycomb structure inside.

I don't see firearms companies using it until machine costs come down.

Iirc, the first laser sintered 1911 cost about $100,000 to build on a $1 million machine.

Look for 3-D printing to make prototype parts for investment casting (AKA 'lost wax').

Supposedly Daniel Defense is producing their suppressor via 3D printing

Cost per part=(total materials+machine setup time+production time)/number of parts produced.

With conventional manufacturing, setup time is long (jigs and fixtures, process design, etc.) But manufacturing time is very short - once set for a particular twist and length, a barrel rifling machine will just keep spitting them out.

With additive machining (3d printing), setup time is short - load design into machine, refill raw material supply.  But the manufacturing time is very very long.

For every part there will be a certain number that is the switchover point, where the added setup time for conventional machining balances the long production time for printers.  Manufacturers will figure those numbers out pretty quickly - it's pretty basic engineering economics.

Or look at a real life example - actual printing.  Laser printers didn't displace offset printing - they only took the market for very small production runs.  But they also spurred the makers of offset presses toward making the changeovers faster between print jobs.

Daniel Defense 3d printed supressor

Looks very cool!

I agree with what everyone has posted. Technology isn't/may never be there for high volume production with ideal materials. Still interesting to see how it continues to be used in industry though!

3D printing is not the correct technology to use for mass production.
It's designed for one-of's, testing, R&D. It may come down in price (it has been for years) but so will CNC and other techniques.

"I wouldn't use a 3D printer unless it COULDN'T be made by conventional machining techniques."

This is the 'correct' answer.

It is a last ditch way to make much of anything in a mass production environment.
It might even be used to make an injection mod part that otherwise could not be made any other way.

And then switch to that relatively fast injection mold machine.

There are places where metal additive manufacturing makes sense, and a lot where it does not.

In aerospace, some parts are made from crazy expensive alloys, and if done from a solid block with a CNC process where 1/2 of the material is cut away, that really adds up. Note, these parts are usually overbuilt and still CNC machined for the tolerance and finish required.

Instances where one 3D printed part can replace a dozen and more parts assembled into the same part as the additive manufactured one. Siemens had a case study where they had some flame mixer for turbines with instances like this.

Lightweighting parts with small product runs. Using generative design and topology optimization to make lightweight parts that can withstand the required loads.

Crazy metal mixes and gradients. Some of the powder fed additive manufacturing machines can use multiple powder bins and mix metals as it builds, changing the percentages as you go. I've seen parts where stainless was used in some areas for strength, and a copper alloy in others for heat transfer, all one part.

Parts that can't be CNC machined, like the blade with the internal honeycomb already mentioned. Or simpler parts with internal cooling passages that could not have been done any other way (and have one part).

Right now, for firearms, we don't need exotic metals, and the designs are not so complex that they can't be done with multi-axis CNC machining operations. However, some custom cooling apparatus for a gatling style gun, I could totally see.

Just had this conversation with a customer yesterday...you guys have it nailed. 3d printing is very cool but not economical for most things.  As generative design becomes more common you will see very odd organic shapes that are difficult to impossible to machine with conventional tools...but they will be expensive, so the scope of application will remain limited.

Printing will dominate certain apps though...medical devices will be one.  When you need a custom hip or knee..printing makes a lot of sense.   Prototyping is another. But volume production is still the realm of cnc tools and other traditional processes.

Greatly exaggerated.

It has proven very useful to make forms for lost way casting of very complicated aureoscpace parts.

We used to make them by using wax and either molds or hand assembly of complicated wax forms.
After coating the form with other materials to make mold that could resist liquid metal the wax was removed.
Thus the 'lost wax' moniker.

The resulting hollow form could then be baked to suitable hardness, then heated and filled with liquid metal.

3-D printing is a SLOW process.
An automated CNC controlled 'work station' can turn out a complicated machined shape very quickly.

Like a 1911 frame.

Forging will also still be required when metal strength must by increased over cast or sintered metal.
Like a 1911 slide.