On Topic: stripped Moen show cartridge screw

My big concern was the screw threads must me extremely calcified and frozen in the cartridge. Any easy out solution would still have a frozen screw to contend with.

I can't use WD 40 due to allergies to it in the family. I have found that mineral oil, given a day to soak in, works as well as WD40.

But how to get past the knob and screw head to apply it?

I am thinking I have to

2) cut the knob off

Any suggestions on how to cut the knob off?

Maybe put a grinder on my drill and grind the screw head off?

I must be missing something here < ? >

The screw just holds the knob on. The cartridges are free lifetime. Replace the cartridge. Replace the screw. John T.

What you missed was that I have to get the screw out first to get the knob off so I can replace the shield and/or the cartridge.

The screw stripped on me, meaning it is frozen in cartridge.

I'd probably try a small hole saw - just big enough to go around the screw head. < it seems like you'll be replacing the knob anyway >

John T.

I though of one of these to grind the head off:

And if the screw still won't come out, replace the cartridge too. The cartridge is probably 30 years old, so I it seems a good idea to replace it too.

Your thoughts?

The screw is stainless steel - tough stuff. The knob is plastic. I'd cut the knob with a little hole saw ... John T.

Maybe one of those drummels would mess up the knob around the screw.

I hate to do it for jobs that should be easy to do but I have called the plumber for Moen cartridges in tub and shower where there are no shut off valves and I need to turn off all the water.

Given the replaceable nature of the handle, that sounds like the best idea, but in other situations where you can't get a screw out, I suggest left-handed drill bits. Surprisingly, the only low prices set of 4 last I looked, years ago, was at Harbor Freight, although there is one name brand that sells the bits one at a time. Sometimes even the smallest one is not small enough, but when one fits, while drilling the head out, sometimes the whole screw comes out.