thephantom1492 t1_iu532x6 wrote on October 28, 2022 at 4:41 PM

Reply to comment by thirdeyefish in How can I remove a headless screw from a shower valve? by foootrest

There is some reverse drill bits too. They are pricier, but they MAY grab and cause the screw to unscrew.

Captain_Elson t1_iu5c3w7 wrote on October 28, 2022 at 5:41 PM

Theoretically these should always grab when used properly. Generally they come with a kit that has the correct size reverse bit and the associated drill bit. Edit: Just checked and harbor freight sells a whole set of these for like 10 bucks.

You'll want to use the regular, smaller bit to drill a hole into the screw, then (generally with a tap wrench) use the reverse bit to grip on the inside of the hole you drilled. Just back out the screw while the bit is trying to go deeper. I've never had one of these fail on me.

Hardest part is getting the initial drilling straight on the screw, but there is quite a lot of tolerance.

Also, lube up the bit while youre drilling, WD40 works fine for this. And blast the screw with PB Blaster before unscrewing it.

thirdeyefish t1_iu54oln wrote on October 28, 2022 at 4:52 PM

Good point, I had not looked at the photo.

joejc18 t1_iu58rbt wrote on October 28, 2022 at 5:18 PM

Always use reverse bills for extraction. Why are you going to drill a hole and make the screw go in even more. Drill and loosen at the same time or nothing

Skeeboe t1_iu5a3iy wrote on October 28, 2022 at 5:27 PM

I saw a reverse bill on daffy duck back in the day

lochlainn t1_iu6jjwx wrote on October 28, 2022 at 10:48 PM

"You're dissssphicable!"

Richard_Thickens t1_iu7g0b4 wrote on October 29, 2022 at 3:16 AM

Also, soak it in PB Blaster first and wait a while.