? for the insiders of the hobby. How long does it take to produce a model?

[Bowtienutz]

? for the insiders of the hobby. How long does it take to produce a model. I'm curious of the manufacture process. Is a mold 1 body and all the parts? Are the clear parts a seperate mold? Explain what a mold looks like. What is demold time? We've all rumours of Johan molds being carted off for scrap by employees I thought that molds were heavy large things.

Vince

[Harry P.]

An injection molding machine is a heavy, large thing. The molds themselves are only a small part of the whole machine. The mold is a two-piece (or sometimes more) hunk of steel, with the shapes of the parts to be made carved into them. The molten styrene is injected into the mold under pressure, and fills the recesses in the mold to form the plastic parts. A basic mold has two parts (the top half and the bottom half)... but more complex parts require more complex molds with more parts to them, some of which have to be able to slide back and forth in order to allow the finished parts to be able to be ejected from the mold once the plastic has cooled (hardened) enough to hold its shape.

Clear parts are made with one mold, colored parts another, tires another.

[mopar68]

I have a question related to this topic. How do they make the molds? Harry you just mentioned that "the shapes of the parts to be made [are] carved into them". I guess today they make a master, then use some sort of computerized scanner to map the master onto a computer, then use a CNC mill (or similar machine) to cut the shapes. But what about in the 60's when that kind of technology wasn't available (or was it?)? Did they carve the tooling my hand?

Just curious.

[Harry P.]

What you describe is pretty much how it's done today. I don't know exactly when the tool cutting process became fully automated. I'm sure Art will fill us in when he sees this thread.

[Casey]

Watch this and all subsequent Parts:

[mopar68]

Thanks Harry

Watching the first part of that video Casey I can see my guess wasn't too far off. Thanks for posting that up, I found it quite interesting. Well, on the the second part!

[jeffs396]

Yeah and to think, back in the sixties, they used to re-tool EVERY year for the annuals, just like the 1:1s!!!

[philo426]

Wow!Makes you wonder how much more difficult it was to tool a kit back in the day when computers were not as prevalent!

[charlie8575]

I have been exploring this topic lately in possible preparation for launching a firm. And yes, I am quite serious about this.

Most mold modeling can now be done using a process called "Rapid Prototyping," which will allow accurate shapes, sizes, character lines, etc., to within 1/10,000 of an inch. It's really quite something.

Once the shapes are copied, using a scanner that works in a manner akin to a radar gun, reading off of targets on a net-like object, the information is transferred to the computer, where scaled shapes are made. The mold engineer will then work with the draftsman/designer to do parts break-out and arrange the mold's cavities.

Once that is completed, RP relies on a carved polymer material, not dissimilar from what some dental crowns are made from, and scaled parts are made off the computer using a thing that looks like a cross between a router and a coal grate, as the material falls away and the finished object is raised by a pneumatic platform under the modeling medium.

Some hand modeling may still be needed for very fine details, but about 90% of it can be done by machine now. Some details, like contours, may also require a little tweaking by hand, but the vast bulk of the work can be done by machine.

This company is a major producer of the scanner and modeling devices. Very cool. http://www.zcorp.com...ines/spage.aspx

Charlie Larkin

Edited March 26, 2012 by charlie8575

[Casey]

Thanks Harry

Watching the first part of that video Casey I can see my guess wasn't too far off. Thanks for posting that up, I found it quite interesting. Well, on the the second part!

Thank Marcos Cruz, as he was the one who originally posted in here.

[mopar68]

Ok then thanks Marcos Cruz And thank you Casey for re-posting it