On Monday, April 20, 2015 at 8:31:58 PM UTC-7, Ed Huntress wrote:
On Mon, 20 Apr 2015 22:07:19 -0500, "Lloyd E. Sponenburgh"
lloydspinsidemindspring.com wrote:

Martin Eastburn fired this volley in
:

Over hyped by those who want to hear it said.

We appreciate YOUR comments, Martin, whether or not we agree, but WHY do
you keep falling prey to responding to that moron? He's not worth the
breath to say "NO" to.

Lloyd

Excuse this lengthy post -- I try to avoid doing this, but I've been
researching this subject and some readers will find it interesing. In
the issue of FAB Shop coming out in a week or so, I wrote three
articles on AM (additive manufacturing); one is on metals for AM,
another is on a big mold shop that's using it to make premium
injection molds from maraging steel, and the third is on plastic AM
tooling at Volvo trucks. This is the latter. No, neither Volvo nor
Stratasys are among our advertisers. g

AM is overhyped in the consumer press, and some of the trade press is
doing the same, not doing their homework. We're being careful about
our reporting on it and, if you study it carefully, you'll see that
it's creeping up on us from several directions. Under the hype is some
amazing stuff. The auto manufacturers, big and small, are all over it.

I almost got myself into trouble here with the cube/square issue on
which Ned corrected me, but I didn't quite:

=========================================
[headline]

A Pitch for Plastic

[deck]

When a major truck manufacturer starts using ABS plastic to make jigs
and fixtures, it's time for an attitude adjustment about using
plastics in additive manufacturing for fabricating tasks.

[byline]

By Ed Huntress, Editor

[text]

FAB Shop recognizes the many applications for additive manufacturing
("AM," or "3D printing") in industry, but we've taken a cautious
approach when it comes to fabricating. We've paid little attention to
plastics, but AM with plastics is vastly cheaper and faster than AM
with metals, and it is sweeping the table in making prototypes, test
models, casting patterns, and many other industrial functions.
So we sat up and took notice when we learned that Volvo Trucks, and
others, are using AM and ABS plastics for production tooling. Now
they're hitting close to home.

Volvo Trucks has reduced turnaround times of assembly-line
manufacturing tools by more than 94% since incorporating AM technology
at its engine production plant in Lyon, France. Pierre Jenny,
manufacturing director at Volvo Trucks, says that the company has
reduced the time taken to design and manufacture certain tools,
traditionally produced in metal, from 36 days to just two days in
thermoplastic ABSplus using its Stratasys Fortus 3D Production System.
Strength and stiffness aren't just about materials

But how to plastics stand up to the rigors of production metalworking?
A lot better than you might think. It's a matter of applying some
basic engineering principles to get the stiffness and strength one
needs for the task.

We dragged out our dusty Engineering Statics textbook to run some
numbers. You can do this with stiffness or strength, but the results
are similar either way.

Steel's bending stiffness is around 30 million pounds - we won't
bother with units here, because we're just doing a comparison. ABS
plastic is on the order of 300,000 pounds. At first glance, steel
appears to be 100 times stiffer.

But the stiffness of a beam - or a metalworking finger clamp - varies
with the cube of its depth. So, to get the stiffness of a 1-in. square
steel clamp, an ABS clamp only has to be around 4.6 in. deep, for the
same 1-in. width. The ratio is a lot better for ABS versus aluminum.

That sounds like a bulky clamp, and it is. As you can see from the
photos, for unspecified tools, they have a massive appearance. But so
what? And the AM plastic can be made into much better structural
shapes than a plain rectangle. In terms of material usage, the ABS
clamp can be much more efficient, because you don't have to machine or
weld the structural shapes. You just draw the shape you want in CAD
and push a button. Often, you can make a tool in one piece that used
to require several.

Volvo's Jenny has worked out the cost on a per-cubic-inch basis. That
may sound like an odd way to compare tool costs, but not so much when
you think about how easy it is to make that plastic into any shape you
want with AM. The all-in cost ratio is roughly 100:1. Metal tools at
Volvo Truck cost 100 times more per cubic inch than plastic ones.

No doubt, more readers are now sitting up and taking notice. So you
have a process that saves 94% of the time to make tools, and their
finished cost, on a cubic-inch basis, is 1/100th as much.

Jenny says "Stratasys 3D printing has made an incredible impact to the
way we work. The capability to produce a virtually unlimited range of
functional tools in such a short timeframe is unprecedented and
enables us to be more experimental and inventive to improve production
workflow."

[subhead]
Improvements in Three Months

Within three months of buying their AM machine, Volvo Trucks had
already 3D printed more than 30 different production tools. These
include durable but lightweight clamps, jigs, supports, and even
ergonomically designed tool holders that produce a more organized
working environment.

"We're working in the heavy-industry sector, so reliability is
naturally critical. So far, every piece that we have 3D printed has
proved to be 100% fit-for-purpose," adds Jean-Marc Robin, technical
manager, Volvo Trucks. "This is crucial from a practical aspect, but
also instils trust among operators and quashes any traditional notion
that everything has to be made from metal in order to function
properly."

According to Robin, developing production tools using AM also enables
the equipment design team to be far more responsive, including coping
with last-minute design changes.

"The fast and cost-effective nature of additive manufacturing means
that we are far less restricted than we were even six months ago,
allowing us to constantly improve our processes," he says. "We now
have operators approaching our 3D print team with individual requests
to develop a custom clamp or support tool to assist with a specific
production-line issue they might be having. From a time and cost
perspective, this is unimaginable with traditional techniques."

We used a finger clamp as an example for our stiffness comparison
because it's close to a worst-case. The majority of tools for gauging,
aligning, and other fabricating and assembly jobs don't have to bear
such heavy stress loads. Having the ability to make a jig or fixture
in hours, rather than weeks, suggests that a lot more time-saving
tooling can be made in plastics - tools that might not even be
considered if they were made with traditional methods.

Stratsys is a multinational company, one among many builders of AM
machines, but they have put some real thought and development into
industrial tooling. The Volvo Trucks example is just one of many. It's
worth a visit to their website to see what other possibilities are
emerging. It just might spark an idea for a tool you've wanted to
have, but just couldn't justify the cost or the time to make it.

-- end --



"AM is overhyped in the consumer press, and some of the trade press is
doing the same, not doing their homework"


One big reason 3D printing is over-hyped in that much of the commercial trade press that covers the 3D printing is pay for play.

slow eddy is very much apart of the problem and not the solution.