I've done it many times....usually to add the
Korker Studded Felts
You do not remove the old felts.
Take the waders to the car wash and powerwash out all the dirt from the existing felts so they are clean. (This step is key - the dirt on the old felt soles will prevent a good bond if it is not removed)
Let them dry a couple of days at least
Trace outline of waderboot on top of felt sole
Trim replacement felt with heavy shears or utility knife
Put a ton of glue (like a tube's worth for each foot) on the sole of the wader boot and the backside of the replacement felt. Marine Goop or
Korkers Glue is very good for this.) If you use Korkers glue, you need two tubes to do a good job.
Let the glue get tacky (10 mins or so)
Stick the replacement sole to the wader boot
Put a towel on top over the wader boot and sole, or wrap in an old t-shirt or something.
Wrap duct tape around the fabric, wader boot and replacement felt sole to get a tight seal. Let sit for two days. (Very important that the glue sets up under pressure.)
Trim replacement felt with sharp knife or razor.
After trimming, run another bead of glue around the seal where the sole and the replacement felt meet. Let sit another two days.
That's it....