: This has been discussed before. William gave
: you a solid explanation as to why scale
: model kits can very. Actually the same
: molds can produce parts that will vary with
: each production run. I worked with making
: plastic parts years ago, and I doubt that
: things have changed about a lot of "art
: form" is required. Mold cooling
: settings, speed of the molding process
: (injection and cooling down) and operator
: experience makes a big difference.
: Dick gave an estimated scaling for the two
: kits that basically works out to 1/700 +/- 3
: units (whatever your dimensions being used
: ... say the real ship is 700-ft long, then
: we are talking +/- 4-ft ... the kit will be
: only a small fraction off), or 0.4%. That
: is so minor that the human eye isn't going
: to notice the difference if both kits are
: side by side. Plus where and now you
: measure a kit to determine if it comes close
: to the desired scale is important.
: Shrinkage of plastic varies with the
: structural design of the parts and
: "generally" is greater in length
: than width for something like a hull.
: Everything is made, even the items you
: describe, with tolerances applied so that
: mating parts fit. The tighter the
: tolerance, the higher the cost. Pipe
: fittings are generally worked out to a
: tolerance level and MASS PRODUCED when
: everything is set. Plastic Pipe itself is
: extruded in large quantities and is
: different material that what model kits use.
: Kit makers are pretty much on the lower end
: of worrying about whether they get a kit
: dead nuts in total length for something that
: ends up being only about a foot long. They
: should worry about other things in making a
: quality product ... like does the hull look
: like a Tanker instead of an Aircraft
: To me the really important concern with kits
: is ... did the model kit maker get the
: fitting of the various parts correct. Do
: they do fit checks during the design process
: and pre-production process to be sure
: everything fits together as desired??
: Something like fitting of a lower hull to an
: upper hull half can really be a problem if
: they didn't pay attention to details. This
: is where Trumpeter many times fails the test
: of a quality kit to me.
: --Previous Message--
: ...handle dimensioning wrt everything from
: pipe fittings to OEM aircraft components.
: We certainly have access to appropriate
: dimensions of--say--CV-6.
: I don't understand why the cutting of the
: molds and the process of shoving out the
: product somehow manages to avoid fidelity to
: the prototype as often as it
: does...or--theoretically--at all.
: I do understand, and I certainly appreciate,
: that kit manufacturers are turning out
: innumerable and fabulous pieces of work
: which is a far cry from my start with Aurora
: and Lindberg kits so many years ago.
: Still, I can't help but believe that they
: could do better in this one respect. It's a
: fundamental quality of the kit to hold to a
: common scale across the board these days.
: They ought to know that.
: Randy Stone