Stubborn 3mm screws

That's over stepping it a little isn't it? :)

set

small

like

releasing,

Not the same thing at all, other than having LH thread of sorts. That's what you use after drilling a hole, but what do you use for say

We only use LH bits only in the hopes that maybe the remainder will spin out as we're drilling. Mostly for small holes where easy outs are not practical. Even with that, our machinist still don't have much better luck, than just simply drilling out the hole as close as possible with a RH bit and run a tap down through it.

Most of the problems I hand over to the machinist have loctite broken screws heads..

:Philips heads , but glued or varnished in and any more torque on the :screwdriver will strip the head. I've tried heating for a minute with :soldering iron, no change. Have now left a dollop of paint stripper over the :heads overnight. Before using a left hand drill or griding off , any other :ideas ? Converting the cut off shaft of a screw driver to somehow fit a :standard (large) impact driver ?

If you aren't succesful at removing the screws, and you don't want to grind them off and then use a small ezi-out - getting that small hole centred is a pita - then you might try the Rolson damaged screw and bolt remover kit

Maplin currently have it on sale for UKP8.99. It claims to be good down to 3mm screws and might be useful for the future.

I've been using a #1 Phillips driver for the case screws on my Icom and Kenwood Ham Radio equipment. It seems to work OK, as long as I use a driver that hasn't had its tip rounded.

Does anyone know if these particular screws are actually PoziDrive?

Fred

In theory Pozidriv screws should be identified by an engraved cross on the head - but I'm not sure this is always done with bright finish ones designed to be seen.

I don't know if it`s always the case with chinese made screws, but a true posidrive screw should have an embossed X on the head at 45 degrees to the X formed by the slots.

Ron(UK)

True.

My best bet however is to try several 'heads' from my driver and see which 'locks in' best. It's often VERY obvious !

Graham

I tried Phillips 0 and 1, as well as Pozidrive 0 and 1, on some Kenwood and Icom case screws. On the Kenwood, all 4 bits felt about the same! On the Icom, the PZ1 felt much more secure.

The Icom screw heads have a small dimple where the PZ "X" might be. Since they are somewhat small screws, I wonder if the dimple is an abbreviated symbol for Pozidrive?

Fred