I'm trying to remove a shower faucet handle, but the set screw seems to be stripped out. Honestly, it looks to me like there isn't much if any of the screw left for an extractor bit to grab hold of, but I'm not entirely sure if I'm seeing things correctly (see pictures below). Any advice?
I assume you want to replace the faucet.
Options:
Drill it out. You don't care if you wreck the stem of the valve.
Drill and try an extractor. I usually never can find one the right size. I have a set. Somewhere.
Once your pretty sure that it's not holding the handle on, you may need additional persuasion to get the handle off.
The handle may be cemented on with calcium/magnesium carbonates (what makes water hard) Soaking in passivated muriatic acid may release it. This will take hours to days. Caution: Review safe acid handling.
If the handle is metal you can try heating it with a heat gun. If the valve itself is plastic this may make life more difficult.
If you decide to to pry it off, protect the wall with a couple of chunks of 2x4. Run them horizontally and pry from above and below. If working alone, you can hold them in place temporarily with duct tape. A 2 foot chunk will span standard stud spacing. This, I think will minimize any flexing of the wall which might crack tile or grout.
A better way may be to rig something using puller jaws and a a slide hammer.
In response to a comment: Turn off the water, and have your replacement parts ready. Depending on how cheap the contractor who built the house was, there may or may not be individual shutoffs for the shower or just hte bathroom. I've done many repairs that required shutting off water the entire house. As a result of this, my first step in a repair is to add additional shut off valves. (I live a 40 minute drive from the nearest big box store. Few repairs are done without at least two trips to the store. Being without water all day isn't a win. I now keep a couple of quarter turn ball valves in 1/2" solder ends (since I have a copper plumbed house) on hand so I can start with that.)
If you do try to drill the screw out a left-hand drill bit might be worthwhile. I've had a few occasions when drilling a broken fastener with a left-hand drill removed the fastener. I don't know that I've ever had success with an extractor -- it's difficult to get the hole centered, the right size, adequate depth.. and then the extractor just shatters in the hole anyway.
The handle could be removed in sections. Using a hack saw or reciprocating saw, cut the main part off perpendicular to the stem and far enough back from the valve body that the saw cuts only handle, not stem. Next cut what remains of the handle along the axis of the stem so that the handle shell can be split into two halves and broken away. A rotary tool such as a Dremel may be useful here. Hopefully at this point you'll have reached the inner part of the handle casting which is actually contacting the stem. Repeat the cut-and-split process on this piece too.
There's some chance of damaging the valve stem or the escutcheon, but both of these as well as the handle can be replaced individually if desired.
Use a 3/8" left-hand drill bit. The drill bit is long enough to clear the handle and has a small enough OD that it won't damage the threads in the setscrew hole. With the drill set to reverse (the cutting direction for LH drill bits), use short bursts, slow speed and check regularly to see if the setscrew has come loose. Be careful not to drill through the brass cartridge stem. Worked for me and the setscrew and handle were reusable.
