Anyone know what the longest scale ruler that's available in 1:87?

General makes a 12 inch ruler marked for 85 HO scale feet with an extra scale foot before 0 and after 85 for a total of 87 scale feet. It also has N,S and O scale, plus 5 inches marked in 64ths, and a decimal equivalents for number drills and reference table for tap drill sizes for small screws. plus 0 to 100 mm.

General also makes a 6" scale rule, and looking at the wear on both my 6", and 12", I'd say I probably use the 6" far more, for modelbuilding.

I've got three 12" rules. Two look almost identical except that the MicroLux is etched stainless-steel and the Excel is printed on anodized aluminum. One other major difference is that the Excel seems to have about a 6" error out of 80' scale. The HO and O scales seem to be OK. The third one is from C.T.T and is printed on clear plastic (one side only), but is N scale only. That seems to be the one I use more than the other two mostly because it's flexible, transparent and goes out to 160 scale feet.

I am not aware of any ruler longer than 12" for either HO or N, but that doesn't mean there isn't one out there...