On Wed, 19 Jul 2017 04:54:28 -0000, wrote:

In sci.physics David Mitchell wrote:
wrote:
In sci.physics David Mitchell wrote:
wrote:
In sci.physics David Mitchell wrote:
wrote:
In sci.physics David Mitchell wrote:
wrote:
In sci.physics David Mitchell wrote:
wrote:
In sci.physics David Mitchell wrote:

snip

Not really - for example, if we're not at the limits of layer hardening time,
then we can use multiple print heads, multiplying the print rate.
I thought that was apparent, apparently I needed to explain it.

But we are at those limits as well as how fast we can lay down a layer
without slopping it around.

Did you think the issue is how fast a stepper motor goes or how fast you
can squeeze something out of a nozzle?

First of all, there are other technologies, the second of the new printers I
posted uses one of them.

All the technologies squirt out something that has liquid properties and
then is hardened somehow, all of them.

Apart from those which don't, such as laser sinterers, or those, such as the one
I linked to, which hardens a resin with a laser.

What part of "is hardened somehow" did you fail to understand?

The bit where you can't imagine 16 laser heads working together?
Or that the technology mentioned above pumps fluid in at a rate of knots?


There are no Star Trek replicators where a complete object forms out of
thin air.

No-one has ever claimed there are.

You were by claiming there are "other technologies".

Don't be silly.
Neither traditional laser sintering, nor the other technology I cited "squirt
out something that has liquid properties" unless by "squirt" you mean "pump"
into a tank.

They are very different to a movable head which deposits material in a 3-D pattern.


Second, even something as simple as adding more print heads would multiply the
printing speed, as I've explained twice now.

What part of we are already at the limit of deposition rate is it you can not
grasp?

The part where you saying it makes it true: it's not.
Unless you can prove me wrong, it's your claim after all, so feel free to
provide evidence.

What do YOU think limits deposition rate, the speed of stepper motors?

Yes; and we're nowhere near the limits of those, the deposition rate FOR THAT
KIND OF 3-D PRINTER, and multiple printer heads would solve that because,
hardening time is not at its upper bound yet.

There were two links posted - I notice you're completely ignoring the second.
There are also other kinds of 3-D printer, and different types will be invented.
Can you honestly not see that, or are you just ignoring it, because you know
you've lost this particular argument?

I see you are ignoring the close up photo showing that what I said is true.

True for that kind of printer, at the moment, and you're still ignoring the
other kinds of technology. It's getting embarrassing.


And again, there is only one type of 3D printer; a machine that takes
a material that has fluid properties and deposits it in thin layers
which are then hardened.

It makes no difference if the material is thermoplastic that has been
heated and then allowed to cool or micronized metal particles which are
then sintered together with a laser or electron beam machine.

Just not true. FFS neither of the other two kinds of fabricator I mentioned
work in that way. Read the article!

Since you are such a dense littlt twit, I will type slowly so that you
may understand.

Since you're still ignoring the system I cited, let me explain *it* to you:
polymers are pumped into a tank, a laser scans it, hardening it in places.

Note there's no moving "deposition system", just a moving "hardening system".

The the hardening system is moving and not the deposition system is a minor
nit.

Not at all, since it's your claim that "we are already at the limit of
deposition rate" which you assert imposes limits on the process.

See: https://en.wikipedia.org/wiki/3D_printing_processes

Nothing particularly new or Earth shaking

"10 to 100 times faster"

and it also just prints plastic.

"The entire polymer family". Plastics do have quite a lot of useful properties.
Apparently they're the future.

Plastics were the future in 1940.

Apparently they were in 1967, too.

https://en.wikipedia.org/wiki/The_Graduate

Not necessary in the above; but carry on.

You certainly are a naive nob.

What do you think positions the hardner?

Just watch the video: http://www.popsci.com/fastest-3-d-printer-ever
The laser scans the surface of the material, from below.
Four lasers would be four times as fast.

Note that this doesn't have to be particularly accurate if you are tracking the
deposition system with a laser, which *is* precise, so you're not squirting a
fine trickle, you're firehosing it out, at the highest speed it can be hardened;
with multiple heads, if you want.

Christ you are a naive nob.

The level has to be controlled rather carefully.

I know you won't have heard of it; but there's this thing called adaptive
control; and you can use it to raise and lower the plate below which the
material comes so it's at precisely the right height above the surface you're
building on. I know, right?!

Christ you are a naive nob.

The level has to be controlled rather carefully.

It's also very fast, obviously, even when I first started working in embedded
systems 35 years ago, we could drive a hydraulic chisel over a surface at
5cm/second with sufficient accuracy using an 8-bit processor running at 16MHz.

Things have rather improved since then.

So ****ing what?

The accuracy of the final printed product is directly related to how
small an amount of material can be deposited at one time.

As you can see from the above, this just isn't true.

Change the above to "deposited or hardened" and the problem is fixed.

Nice to see you actually learn something.

BTW, just what the **** does all this have to do with a totally 3D printed
car or printing with anything other than plastic?

Nothing, other than some hallucinations about the perfect future
(where flying cars fold up into brief cases).