OPEN HOLE CUPS
Metal bushings must be replaced with JS leakproof Delrin bushings (other brands of plastic bushings do not seal well with Digital Gold pads). These bushings slide on and off smoothly and make shimming an easy job while reducing the likelihood of damaging a pad. The delrin bushings and gaskets are essential for JS pads because they are flexible and provide a seal against the inner collar (metal bushings will leak). If there are too many partial shims and the pad is tilted, it will leak at the bushing and need special thicker bushing gaskets. Order bushings that are .1mm (.004") smaller than the outside diameter of the cup chimney.
There is an aluminum collar hidden near the center beneath the skin. Avoid using a metal tool when prying up a bushing or you may pinch the skin against the hidden collar and cut it – use your fingernail. If you must use a tool, only catch the outside edge of the bushing (do not insert the tool too far).
DELRIN BUSHING KIT
Delrin bushing kits come in a 6 compartment container (5 per size) from 7.6 to 8.1mm Sizes 7.5 to 8.3mm are also available.
DELRIN BUSHING UPGRADE KITSRequired for Yamaha 500 series & up and for some older flutes with tapered cup chimneys (old Haynes etc). Stainless steel sleeves slip over the old chimneys and provide a new straight surface for the delrin bushings.
GO HERE FOR BUSHING UPGRADE DETAILS