new tooling question, somehting that has always had me wondering

[rsxse240]

I saw today how plastic bottles are made, as well as how real engine blocks are made, and it got me to thinking. How do new tools come into fruition? I am guessing that they have to be mastered from someone actually building something from scratch, but how do they make these intricate molds out of metal for injection molding? Are they even made of metal?

I wouldn't think they would just make a tool that cost THOUSANDS of dollars in materials and man hours (or computer programming for a C&C machine) for a mock up model so they can find that the parts don't fit together, or to find out that NO ONE will buy it (though marketing research takes care of the last part).

I'm sure some of you fine modelers on this forum are in this business, won't you share with us all how this process takes place? Or atleast point me in the right direction. This is just a curiosity that has puzzled me ever since I started building models.

[freakray]

Stereo Lithography is one technique to prototype, then negative form pattern making.

What kind of plastic bottle manufacturing did you see, blow molding?
Bottles and engine blocks are made different ways depending on what material they are made of, take everything you saw today and only apply it to what you saw.

[ZoomZoomMX-5]

In the old days (and perhaps currently) they basically made a set of wood or resin patterns of each part in the kit. These parts are scratchbuilt to the blueprints, and the pattern like the final kit. The pattern is oversized; I'm not sure what scale but it's anywhere from 1/8 to 1/12 scale IIRC for most models. I could be wrong, and there may be some newer techniques used nowadays.

Basically the patterns are then scanned w/a pantograph machine that cuts tooling to the right scale from the pattern. Basically think of a penpoint going over every surface, and a multi-axis milling machine cutting the exact same contours. Nowadays it may be laser guided. Once the tooling is cut, then there is laborious hand work to polish the cavities and finesse the details. Textures can be etched into place. Lots of hand work on the tooling at this point.

Many places can take digital modeling files and cut tooling from that. Not sure how much of this is used with models; it's a very risky thing for a model if everything doesn't fit as designed w/tooling tolerances. They make many adjustments to the tooling once test shots are run and parts are assembled.

[gionc]

Yep: that was yesterday

Today with parametric 3d solid modelling software (SolidWorks, ProEngineer, Solid Edge, some others) you'll directly design (in solid, so you'll check all piece's fittings) and like Ray said, do a rapid prototype. There are several techniques: stereo lithography, syntherization, 3d printing, I leave you to discover the differences: basically STL give you a well formed proto but with a very fragile material, you can only cast in resin to do fitting tests, drill, mill down etc. sintherization make a proto with thecnical capabilities of be milled, drilled and so, and it's done by nylon, but it's coarse, very rough.
d printing is the new way to form objects by layers of a material like wax, narrowed the lyer, higher the resolution.
Let me show the entire workpath from the PC, trough the proto to the injected platic shape, just a minute to take picts.

[gionc]

(Preface: my job is design, so this is my bread LOL, preface2, I'm using thise new tools also in the modelling world, I'll show soon something, for the moment accept this OT subject, at least tech used are exactly the same, to do resin stuff like Hiro, doing a mold from teh proto, or to do injected stuff like Tamy and Hasegawa do by CNC machines from ages, I wannot add something about my english, you know already it's crap )

Stage1: the 3D design: I skip all the stage from teh scketch to this very final stage, basically I started designing main surfaces, than solidify them and added details like column to fix electr. boards and stuff. The subject is a cabinet for a wireless stuff: this is what I have from the PC, ready to prototype, they're renderings I sent to my customer for a final check before do protos:

Cabinet done by a box and a cover: cover:




and the other:





like you see it have all details designed: if it were a car body, it would have window gaskets, screw housing, panel lines, all well detailed.

Foolowing stage 2 and 3, proto and final product.

[gionc]

The prototype was done by a service, in sintherization, basically very similar to STL , both done with a laser ray, STL with fluid resin, sinth. with nilons powders: so far the proto



both the same stuff, I finished with our modelling techs the left one to let the customer show it to a meeting: other views:



note the pattern, and nylon isn't so good to sand down!! Hiro's fan recognize something? the same crappy pattern we find in our loved iron pieces LOL



HERE the "new tooling" job finish for people like Hiro or R43: if the proto is ok they just do RTV molds and cast it, next step is only for people like Tamiya and few others that need to do injected stuff:

after few other (internal) mods I had ready the final file and given it to a mold shop to do the steel mold necessary to cast the plastic: this is the result:





hope I was clear enough, hope you'll understand the text

ciao
gio

[ZoomZoomMX-5]

Thanks Gio; it was late when I replied so I figured I'd miss something like stereolithography or SLS like the parts you've shown (yes, that nylon is tough, better than the brittle parts from stereolithography). Some companies take shortcuts and don't print a 3D prototype to prove the construction, they go straight to tooling. Risky, but cuts down time...

I need to learn Solidworks myself; I learned ProE a long time ago but our company was so screwed up I never got a chance to use it in practical terms before I left, and haven't done any 3D design since then. I've worked w/several of the rapid prototyping methods, in fact I have one sitting on my desk right now for a work project. It won't be that long before we can all have 3D desktop printers that can do what you showed. Now if only there was less finishing work or better resolution on the parts as they come off the machine

[gionc]

@ Zoomzoom: to be 100% honest I don't use only SoliWorks: I use SolidThinking (a nurbs SW similar to Rhino) to do the surfacing job, from the sketch to the presentation, when shape is ok for the customer I switch to solid with SolidWorks and it, like ProE, is awesome to do it. I haven't skills in proE but using it with some customers I see is not so far from SW speaking of commands and general philosophy.

Learn it: it isn't a nightmare to do like Lightwawe, just follow a couple of tutorials and play

On the finishing issues: you're right, but I show just SLS that is the worst way meaning smooth surfaces but is the only that will offer some decent mechanical property to try an object: I tried time ago SLT and the surface was pretty good, I would say "approx 2000 grit finished" LOL but the piece go broken just seeing it.

Like I said I'm doing something, I have ready a couple of project in scale, I'm defining parterships since I want share in a "ken's rally way" to pay costs, over the summer I would be ready to share the entire workpath from the idea to the model on the AF.

[bigfrit]

Wow, that's some truely skilled workmanship. Thanks everybody for the read, it was well worth it.

And gio, making a plastic winebottle? wtf?

Good stuff, good stuff!

Oli

[gionc]

Originally Posted by bigfrit

And gio, making a plastic winebottle? wtf?

SACRILEGE!!!!!!!!!!!
A sacre stuff, old like the world..... dressed in mere plastic???
My God, think something, do that oil wells finish soon (and so W bombs, probably) at least we'll do medels from mais amid LOL!!!!

[hirofkd]

For actual mold making, they use the technique called electro discharge machining.
http://en.wikipedia.org/wiki/Electri...arge_machining

[Enzoenvy1]

Gio, if I lived near you, I think I would be following you around like a lost puppy!!! LOL You get to play with so much cool stuff! All of your skills through work and your etching is so fortunate for you to be able to do. I bet all of us would be happy to do a 1/10th of that stuff. I wish I would have followed my true dreams of graphic design but I guess my Technical Writing degree will pay off. Heck, if you need someone to write about your stuff,.........?! LOL What is that thing though? Looks like a blood tester or something?

[klutz_100]

Originally Posted by Enzoenvy1

What is that thing though? Looks like a blood tester or something?

It's a 1/24 dust-buster

Great explanation and demo Gio

[gionc]

Originally Posted by klutz_100

It's a 1/24 dust-buster

Great explanation and demo Gio

you aren't the first macaco that say me it seems a Black&Decker portable vacuum LOL

it's a wireless monitoring TX/RX: a couple link a PC with monitoring SW with various devices like H2/N2/Oxigen dispencers, incubators, lab's stuff at least, so.

[MPWR]

Originally Posted by gionc

it's a wireless monitoring TX/RX: a couple link a PC with monitoring SW with various devices like H2/N2/Oxigen dispencers, incubators, lab's stuff at least, so.

But ooooo, so streamlined for such a simple box. I guess this must be what's meant by 'Italian design'!

It's a piece of art to put on your desk, and it's a fully functional wireless TX/RX!

I want to see one painted and decalled to look like a Ferrari F1 body!!