Removing stripped screws

Thekwango

Thekwango

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Merlin5 said:
Are you able to link me to the one you got? Would you say it's as robust as a genuine dremel?
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i'll have a gander later this evening when i'm free and see if i can find it. regarding it's robustness vs a real dremel, no idea. but unless you're completely cack handed or are using it a lot the robustness doesn't/wouldn't worry me.
 

Armageus

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Merlin5 said:
I'm not sure that test is the same as the thread pitch you're talking about though.
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Thread pitch is how close the threads (the little spiral around the edge of the screw/bolt) are together, can also be referred to as tpi (threads per inch).

So a fine thread pitch has the threads closer together (typically 0.75mm on a "Fine" M6), whereas a coarse thread they are slightly further apart (typically 1.0mm on a "Coarse" M6). There are however other variants, e.g. 1.25mm is also a possibility.

Using the wrong thread pitch will feel like the screw is cross threading.

If you know the length of the screw e.g. 25mm you count the number of turns, and divide it, so 25mm / 20 turns = 1.25mm
 

Merlin5

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Armageus said:
Thread pitch is how close the threads (the little spiral around the edge of the screw/bolt) are together, can also be referred to as tpi (threads per inch).

So a fine thread pitch has the threads closer together (typically 0.75mm on a "Fine" M6), whereas a coarse thread they are slightly further apart (typically 1.0mm on a "Coarse" M6). There are however other variants, e.g. 1.25mm is also a possibility.

Using the wrong thread pitch will feel like the screw is cross threading.

If you know the length of the screw e.g. 25mm you count the number of turns, and divide it, so 25mm / 20 turns = 1.25mm
Click to expand...

Thanks. Yes, the threads on the new M6 screws that the shops had were definitely a bit closer together than on my screws. Assuming then that those were fine M6, a coarse M6 might work if I could find one. Then again, as my screws seem to be slightly thicker/wider across like maybe half a millimeter or so, I don't know if any M6 would work but I'd certainly like to find a coarse 1.0mm M6 and try it. The independent shop was closed so I'll pop over there tomorrow and see what he's got.

I don't know if I'm doing your calculation correctly. I've got two screws. 25mm long with 15 spirals and turns and 20mm with 10 spirals and turns. So that's 1.66mm and 2mm. I've done that wrong haven't I?
 

Terminal_Boy

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Those tapered screw extractors are fine on hard metals that aren’t going to spread out and grip the sides of the threaded hole the screw/bolt with the mangled head is stuck inside.

What you really don’t want to do is to spread the stripped screw/bolt so much that it cracks what it’s stuck inside.
 

Bubo

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Don't know if it is too late but an left handed drill bit would have been my method. Drill into the head with a left handed bit, can be quite a small drill bit, does not need to be the same diameter or bigger than the screw so won't affect the existing hole. With the bit being left handed, the rotation of the drill will be in the direction of "unscrewing". The screw will likely go "You know what, I think I will unscrew now, rather than be fully drilled out", once you start drilling it.
 

maddness

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