I am primarily a tennis player, but I played badminton regularly with the Garden City Badminton Club in Garden City NY for several years.
The machine I use for stringing is particularly well suited to badminton stringing. In addition to a rock solid mounting system and Japanese engineered tensioning head I have outfitted the machine with Babolat diamond dusted clamps for unequaled precision.
A word about badminton grommets. Especially on older racquets it is often necessary to replace large numbers of grommets to ensure the integrity of the stringing. I do not charge for the first five grommets I replace in any one frame. Beyond that though I charge 25 cents/ea.