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I believe attached sketch (not to scale) is what Mike needs -- ie, railroad ties (slots align the rails the proper distance apart).? Not really well suited to a moulder.

18,000 sounds like sort of a lot, but it's still just one batch.? It doesn't make sense to spend more time setting up a fancy machine than the time it will save processing the one batch.

This is also obviously trivially simple to do with a shaper, but two passes required.? It probably makes more sense to just buckle down and face a few days of non-stop, dull, repetitive work, rather than build something.? Let's say?you gang up 10 at a time and slide them through.? Suppose it takes 30 seconds load up 10 pieces, 5 seconds to run back and forth, 15 seconds to flip the 10 pieces end to end, another few seconds to run the second slot through, but not back (helper unloads on the shaper outfeed side after second pass).? That's about a minute per 10 pieces, which is 30 hours for 18,000.? Let's say you budget double that time, it's still less time than building a custom machine with shafts and pulleys, etc.? ?A double router table like I described could be built in a day, and might halve the processing time.?
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