A reed substitution chart is a great way to extend your reeds to be used at a wide range of setts.
For example, a 10-dent reed doesn’t always need to be used to get a sett of 10 ends per inch. You could also use a 6-dent reed sleyed “1-2-2” or an 8-dent reed sleyed “1-1-1-2” to get the same result.
To use this chart, find the reed size you are using (e.g. 6 dents per inch) and then look down the column for the sett that you would like to use (e.g. 20 ends per inch). Then look across the row to the first column to find the sequence to sley in the reed (e.g. 3 ends, 3 ends, and 4 ends).
Note that the values in this chart were calculated directly from this formula and may differ slightly from other historical references that you might encounter:
Number of Ends in Sequence ÷ Number of Dents in Sequence × Reed Size = Sett (round to nearest 0.5)