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Joining 6990/6921 & 6921

G'day all looking for some ideas on how best to combine these two sets. I was also thinking if using one if the railway crossing sets that are modified with extra straight pieces as a sort checkpoint anyone have any suggestions


  • OldfanOldfan Chicagoland, IL, USAMember Posts: 673
    edited December 2013
    The instruction books for #6921 and #6347 (scans available at show a couple of different ways to combine the extension sets with #6990 and #6399 respectively. That should give you some ideas for a starting point.

    For more complicated layouts there are some homebuilt programs in the netherwebs (I thought I saw them here in a forum post but can't remember) that can be used for planning both LEGO monorail and LEGO train track systems, but just using track from my single #6990 and #6991 and 3x #6921 sets, I can just start putting track together free-form to build around my spacebase...
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