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Forums - News / General |
For General modelling or hobby-related topics that are not covered by any other specific forum. Please keep to topics concerning the hobby. |
| Topics | 2899 |
| Messages | 21057 |
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| Subject: | Re: Missing or Wrong Parts in Kits |  |
| Date: | Jul 20, 2002 |
| From: | | |
Landon -
The frames (sprues) are almost always packed by hand on an assembly line, and
human error is likely to blame for the missing frame and the incorrect decals.
This usually happens when the packing line is changing from one kit to another
or when there is more than one packing line running at the same time in the
same work area.
A complete frame being missing is usually not as much of a problem as are
molding defects: short shots (mold not completely filled with plastic), sink
marks (the mold is filled but not enough to make up for the normal shrinkage
that occurs when the plastic cools - thick parts can't be filled enough under
usual cycle times to make up for normal shrinkage without adding a blowing
agent to the plastic, and I don't know of any kit manufacturer who does this),
blown molds (flashed parts due to inadequate clamp pressure, too high injection
pressure, excess material from earlier shots blocking the mold, &c)), burnt
edges (plugged vents), or warped parts (taken out of the mold too soon or
placed so that the still warm plastic is under stress and sags).
The decals were likely made by a separate manufacturer, delivered to DML in
bulk, and placed along the packing line in a pile. If someone dropped or
knocked over a pile, your extraneous sheet could have got mixed in.
Most manufacturers have decent quality control processes that catch the big
mistakes ("Fred" keeps forgetting to put in the frame you're missing), but qc
sampling won't usually catch the rare goof until it becomes more pervasive. Of
course, management can choose to ignore qc, as likely happened when Monogram
ran & shipped loads of Bf 110Gs with an extra lug of plastic on one fuselage
side from a damaged mold, or ICM ran & shipped the first batch of Spitfire IXs
with flash, burnt edges, and sink marks before the gates and vents were
balanced - I don't recall a similar example from AFV kits, but other members
might know of some. This is a separate issue from having too few bolt heads or
dimensional inaccuracies; qc doesn't have anything to do with that.
There have been some videos of plastic injection factories that every modeler
should have a look at to better understand how we get the things that make us
happy. Working in these factories is hot, hectic, noisy, and not a little
dangerous. The pay is not generous for the machine operators and worse for the
line packers.
The injection machines usually have to be opened and the frames removed by hand
or the frames allowed to drop and then get picked up. The machine's cycle time
is set on order of the production manager, and it usually gets faster as the
job goes on. The best kits have frames that were molded after the molds warmed
up and all the technical glitches were worked out, but before the production
manager decided to start messing around with faster cycle times. Hey, it's a
business, and faster cycle times equal lower costs - when the consumer doesn't
notice or has been told that complaints will lead to fewer new products.
The machine operator often has to clip the main injection sprue (in the center
of the frame) and usually packs the frames (still warm, and the combined heat
builds up in this box) prior to their being bagged. One machine does only one
frame, so for example all "Frame A"s usually start out being packed together in
a box, then sent elsewhere in the factory to be bagged (or the machine operator
has to bag them while the next injection cycle is occurring), then packed in
another box and moved again to the line where all frames, instructions, and
decals are packed in the box you buy (which someone has packed into a bulk box
for shipment).
QC should randomly check every major step of the process, but the rare mistake
can get through because every kit box is not inspected. Production managers
usually do not take kindly to having the operators and packers slow down their
work by paying attention to minutiae like parts missing from the frame or
out-of-register decals, and these workers are no more familiar with bits and
pieces of AFVs and military aircraft than any other average joe. The PM
definitely does not want the operators to look for injection problems - this
doesn't make sense, but it is how some PMs work, and seldom are the operators
trained to look for these problems.
Landon, this is probably a lot more than you wanted to know, and there is a lot
more to it than this, but the end point is that your problem doesn't occur very
often, everyone tries to do a good job under often difficult conditions, and
most of the resulting kits we get keep getting better.
Good modeling,
CTew |
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