The Old West Structures

nkp174

Active Member
Oct 10, 2006
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Cincinnati, O.
What???? Don't tell FSM, FOS, Bar Mills, Blair Line and all the builders of Craftsman wood kits in HO and N they have it all wrong and should only do cast resin kits.
rich

Look closely at the wood grain. Laser cut wood kits are popular for two major reasons: Much lower capital cost than injection molding and many people love working with wood. The wood grain is not close to scale in HO. It's principle intrinsic advantage is in staining (and the only reason I work with it even in O scale).

The point isn't that resin is superior...frankly, I don't like working with resin. Rather, the advantages of using the real material isn't as great as in larger scales. This is just like people going to great lengths to get real water on their layout even though it isn't scale.

Look around the hobby. You see styrene 1:20.3 models and wooden 1:160.

If wood is so superior, why do companies like Cimarron Works make resin kits? The molds for resin kits are expensive and require quality masters. It sure seems to me that high end rolling stock has mostly shifted towards either resin or styrene (San Juan, Grandt)...while structures have shifted to laser cut. I have little doubt that a major component of this is the massive cost and time FSM would have to invest to produce a massive lumber mill in resin or styrene is a component in why they haven't offered such a kit.
 

pgandw

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Jul 9, 2005
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Wood and resin are reasonably economical for small production runs (50 is about max for resin without work on molds/masters). A laser cutter is not too expensive, and can pay its way fairly quickly in the production of quality wood kits with accurate pre-cutting of parts. Usually, the laser cut wood kit has a better fit of the parts than the old method of using steel stamps and cutters.

Resin kits require very good masters. The molds are relatively cheap, but will only last for a production run of about 50 in most cases. Then a new mold must be made.

Soft metal casting using spin casting, lost wax, or other techniques not requiring steel dies can also be done as a low production rate process. This can be used for small parts, but locomotive boilers don't count as small. Again, quality of both the master and the ability of the mold material to pick up detail and hold shape under the pressures of the casting process are key.

Styrene and cast metal benefit greatly from steel dies which are very expensive to cut - at least 5 digits, and 6 digits for a more complex series of molds. This drives the minimum batch size of styrene and die casting into the low thousands. While cheaper aluminum dies have been tried, these don't hold up as well in the casting process.

just my experiences