HO Scale Railroad Spacers
This is a set of dual and triple HO scale rail spacers for laying out your model trains.
These are OpenSCAD files so you can create custom spacing, and as far as I know there is not a tool out there to align 3 sets of rails at a time. Each one has screw holes so you can put stuff in place and screw them down to hold things in place.
Also included is something else I have never seen, a spacing tool for track bed foam such as the one from Woodland Scenics. That foam has a center slot in it that is used as a cut mark when you need to bend the foam around curves. I made a block with a tongue that fits in that slot so you can space the foam evenly.